Jump to content

Recommended Posts

How I work out how much area I need to plane efficiently, call it a coef. if you wish, is to look at the horizontal or near horizontal surface area and come up with a kgs/m² number.

I'm guessing this is what you are alluding to WRT CP's.

Most speed boat run around at 25° dead-rise, but they use tunnels and strakes which are not so fast on a boat that is predominantly going to be doing HS.

I dis-regard anything with a deadrise of greater than 25-30° and heavily discount, based on Sin, anything under 25°.    But you have to factor it up, because empirically doing say 12knts when you start to come out (to a significant degree) even at 20-25° the water will simply move sideways (without strakes or tunnels to constrain it) so it's lifting potential is not that great.   Very much a fudge factor.   By the time you’re doing 20knts front ½ of the boat is well out of the water, so what angle it is irrelevant except when you plunge, and then you want it to be fine, so you don't baulk/slam.

That’s my process, so this boat (89er) is thinner than say Vivace because a) it’s longer, so ipso factor it has more surface area (due to length) so it dose not need to be as wide and b) it’s likely to be able to travel at a higher quasi displacement speed with a smaller negative effect, than Vivace (due to length) so it can be opted for a higher “take off speed” (as in full planning.)

~~~~~~~~~~~~~~~~~~~~

Re the Thai Starboard company, they do really nice Windsurfers and i-Foilers and are very techy.

They would have to re-invent themselves to be the next breakout boat, because, sure a lot of people like and love windsurfing. The number of sails that are still being made each year is staggering and even in those days when people where very prematurely calling time on windsurfing, 40-50,000 sails where being pumped out of the big makers per year and still are.

If that’s death of a sector, then that’s a great way to die!

So I doubt Starboard will be the one, and I think they are Dutch, that is not a problem but they are not Asian.   Lessons learned when you are young are very hard to un-do.

Fully immersing yourself in the culture helps, but unlikely to wipe it out, nor would you wish it to, completely.

  • Like 2
Link to post
Share on other sites
  • Replies 545
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

So I'm building a 89er for myself, there is a possibility of a sister ship being built, but really, at my age, and with Covid and wanting to sial with mates around Australia, I'm doning this for me, m

The stuff is known as Basalt Fibre, but Granite is cute! Glass fibre is just sand melted, Basalt is just Granite melted, same process, it's a very dark brown, almost olive-brown in colour.    T

Posted Images

8 hours ago, JulianB said:

How I work out how much area I need to plane efficiently, call it a coef. if you wish, is to look at the horizontal or near horizontal surface area and come up with a kgs/m² number.

I'm guessing this is what you are alluding to WRT CP's.

So what is your magic number? And at what speed? Do you factor in leading edge width, angles or perimeter? You hinted at (bow wave?) angles? Mine is ~ 290 kg/m2 without any modifying factors.

Prismatic coefficients have little to do directly with planing, they are an indication of the displacement volume distribution, or fineness of the ends. Your stern sections don’t look fine on plan, but they are in profile. A higher Cp can help to shift HS up from 1.34*LWL^0.5 to a better number off wind for more conventional boats. Hard on the wind, a higher Cp usually means a slower max HS, especially in chop. Having a Cp of, say, ~ 0.7 won’t necessarily guarantee that a boat can plane early or even at all, but would pretty well guarantee that it will be a dog upwind.

Traditionally, HS > 2.0*LWL^0.5 was regarded as planing. That equates to ~ 10.8 knots for the 89’er. So if you say the 89’er target speed is ~ 8 -9 knots upwind, then clearly it won’t be planing, especially if by your own rules of thumb, you need an SCP of< 4.0 and the 89’er has > 6.0.

  • Like 1
Link to post
Share on other sites
16 hours ago, JulianB said:

How I work out how much area I need to plane efficiently, call it a coef. if you wish, is to look at the horizontal or near horizontal surface area and come up with a kgs/m² number.

 

I'm guessing this is what you are alluding to WRT CP's.

 

Most speed boat run around at 25° dead-rise, but they use tunnels and strakes which are not so fast on a boat that is predominantly going to be doing HS.

 

I dis-regard anything with a deadrise of greater than 25-30° and heavily discount, based on Sin, anything under 25°.    But you have to factor it up, because empirically doing say 12knts when you start to come out (to a significant degree) even at 20-25° the water will simply move sideways (without strakes or tunnels to constrain it) so it's lifting potential is not that great.   Very much a fudge factor.   By the time you’re doing 20knts front ½ of the boat is well out of the water, so what angle it is irrelevant except when you plunge, and then you want it to be fine, so you don't baulk/slam.

 

That’s my process, so this boat (89er) is thinner than say Vivace because a) it’s longer, so ipso factor it has more surface area (due to length) so it dose not need to be as wide and b) it’s likely to be able to travel at a higher quasi displacement speed with a smaller negative effect, than Vivace (due to length) so it can be opted for a higher “take off speed” (as in full planning.)

 

~~~~~~~~~~~~~~~~~~~~

 

Re the Thai Starboard company, they do really nice Windsurfers and i-Foilers and are very techy.

 

They would have to re-invent themselves to be the next breakout boat, because, sure a lot of people like and love windsurfing. The number of sails that are still being made each year is staggering and even in those days when people where very prematurely calling time on windsurfing, 40-50,000 sails where being pumped out of the big makers per year and still are.

 

If that’s death of a sector, then that’s a great way to die!

 

So I doubt Starboard will be the one, and I think they are Dutch, that is not a problem but they are not Asian.   Lessons learned when you are young are very hard to un-do.

 

Fully immersing yourself in the culture helps, but unlikely to wipe it out, nor would you wish it to, completely.

 

Does an Asian breakout boat jettison historical/cultural baggage?  Or, for lack of a better term, redefine it?  I’d argue the Laser redefined the western sense, without jettisoning it.  But, say, looking at what China (and some other countries in the region) has done in the last few decades with architecture, that might argue for the former (jettison) as an ‘Asian’ state of mind as far as new stuff is concerned. If that new architecture expresses ‘we will make the west look like an antique’, that would go along with bringing in western designers for buildings and cars, which might mean more the Starboard model.  But if the Asian sailing zeitgeist is looking for something different than western skiffs, Oceania might serve? Western tech and cultural expression is kind of a sliding scale anyway.  And I’d argue it could hinge on scows, at least at the mainland Asian end of things
 

Jim Antrim design for Barry Spanier-

http://antrimdesign.com/rosie.html

33FE1C8D-5D90-4E85-AA7D-3EC57E02EDAB.jpeg

Link to post
Share on other sites
9 hours ago, Sidecar said:

So what is your magic number? And at what speed? Do you factor in leading edge width, angles or perimeter? You hinted at (bow wave?) angles? Mine is ~ 290 kg/m2 without any modifying factors.

Prismatic coefficients have little to do directly with planing, they are an indication of the displacement volume distribution, or fineness of the ends. Your stern sections don’t look fine on plan, but they are in profile. A higher Cp can help to shift HS up from 1.34*LWL^0.5 to a better number off wind for more conventional boats. Hard on the wind, a higher Cp usually means a slower max HS, especially in chop. Having a Cp of, say, ~ 0.7 won’t necessarily guarantee that a boat can plane early or even at all, but would pretty well guarantee that it will be a dog upwind.

Traditionally, HS > 2.0*LWL^0.5 was regarded as planing. That equates to ~ 10.8 knots for the 89’er. So if you say the 89’er target speed is ~ 8 -9 knots upwind, then clearly it won’t be planing, especially if by your own rules of thumb, you need an SCP of< 4.0 and the 89’er has > 6.0.

So 60 pounds / sq foot?  This gets rapidly into the incredibly fun world of surfboard shaping - displacement logs on one end to Simmons/Lord hulls on the other end. There is a good story of a couple of guys being towed behind a motorboat on their logs and things get really bogged down as the motorboat accelerates.  So the guys step forward, ride the nose and off they go! (This sounds familiar :lol:).  And the infinity of shapes between. Lindsay Lord liked .3 to .5 length to beam, but I’d have to look up what he thought about loading.  There’s a pic in this link of a rum runner of the 30’s that looks interesting:

https://infoamed.com/2020/09/12/revisionist-history-did-tom-morey-really-invent-the-bodyboard-design/

 

 

  • Like 1
Link to post
Share on other sites

Nice look at one of Simmons longboards-  he really keeps the nose up at speed in the Vimeo 

If you take the loading of the back end of the boat when planing as 220 lbs, and the board is planing on 4’ (?), and it’s 2’ wide, that’s a loading of 27.5 lbs/ sq ft, Lord aspect ratio of .5, which starts to look like an early formula board, before the conclaves started appearing.  Double fins.

Link to post
Share on other sites

Actually found Lindsay Lord’s ‘naval architecture of planing hulls’. Pictures and results of tow tests of different shapes etc.  might be interesting if anybody hasn’t seen it already-

https://etchellsfleet27.com/wp-content/uploads/2019/08/Naval-Architecture-of-Planing-Hulls.pdf

  • Like 3
Link to post
Share on other sites

Re Asia and where they may go.

We all sit here and think that we (the West) are the only ones who have built boats and are the bastions of all knowledge.

It ain't so.   Some of the sailing families I am aware of in parts of Asia, their sailing line goes back 1000's of years, and you need to only look at what they could do and the size of their armada's and seamanship long before Magellan was in nappies.  The Indian's and the Chinese, my god, so advanced, and then the first mass seabourne migration was the Aborigines long before even the Egyptians.   40,000 years ago.

Anyway, I think that American marketing post the war, very clever way of controlling a population, embodied what was "good", in terms of image.   Not sure that all of that has sunk in, especially when you get away from the big hubs, so what you will start to see in Asia is the awakening of their image, rather than ours.

For instance, the Topper, fine bit of British engineering, spearheaded by a British ex-Topper class president, who happened to be seconded to China, so China brought 2-3,000 of them 15 years ago.   Don't think they have brought any more, and highly unlikely they will buy any more or RS or Bic or anything like that.

They are becoming far more pragmatic, just because it's "good" in Europe or US dose not mean it will be good in Asia.    And South America is similar.

The Starboards, or the Element6 will have a influence, Element6 more so because of the fluency of the staff in multiple Asian languages (I'm talking the British and American owners) and the ease of logistics with Thailand and the rest of Asia, but there will be a lot of home growth products out of every Asian country, and those products will be very cost effective.    China is the powerhouse, (but India will be very interesting) WRT Asia, just like Brazil is in South America, USA is in Nth America, and South Africa is/was in Sth Africa.

~~~~~~~~~~~~~~~~~~~~

With respect to lbs/ft-sq or in my case kgs/m-sq,

49er is about 119kgs/m-sq,   89er and Vivace are both close to 112kgs/m-sq, interestingly the 29er is up around 136kgs/m-sq and the 470 is way down around 77kgs/m-sq.    All of those numbers are fudges and I can do the 470, because I designed one some years back, so I have the files, no other reason.

This is at what I believe is standard break out attitude and speeds which vary because of changes in HS

But that is not the whole story, the other big factor is power to weight ratio, 29er is about 89%, 49er is 149%, 89er will be very close to 1 (100%, so same RM (kg/m) as weight) and a 470 is about 67%

so a 29er will stay in the water longer, and that is for 2 reasons, a) it's safer for the kids, it's not quite as frisky as say a 49er and b) it's quite possibly a better hull shape given what we know now.  (and it's higher panel loading is possibly why it can achieve higher speeds than a 49er), where as a 49er comes out early simply because it got so much grunt, it just blasts over its bow wave.   But the 89er, it's a displacement toy (80% of the time) and it has the advances of the 29er (hull design) so I expect to to stay in the water all the time upwind, but it also has lot's of potential grunt so I want it to come out effortlessly off the wind.

I do expect to occasionally (quite rarely) do mid 20's in the 89er but to design for that would be rather stupid, and it's possibly 0.001% of the time.   But, as said, it will have plenty of grunt, so I do want it to pop up on the plane effortlessly when we turn the corner at the top mark and play AWA's down hill.

The reality is that, sure I think we have advanced the shape, but Vivace was such a good role model, why wouldn't I just duplicate it's numbers (so I did)!

  • Like 2
Link to post
Share on other sites
3 hours ago, JulianB said:

Re Asia and where they may go.

We all sit here and think that we (the West) are the only ones who have built boats and are the bastions of all knowledge.

It ain't so.   Some of the sailing families I am aware of in parts of Asia, their sailing line goes back 1000's of years, and you need to only look at what they could do and the size of their armada's and seamanship long before Magellan was in nappies.  The Indian's and the Chinese, my god, so advanced, and then the first mass seabourne migration was the Aborigines long before even the Egyptians.   40,000 years ago.

Anyway, I think that American marketing post the war, very clever way of controlling a population, embodied what was "good", in terms of image.   Not sure that all of that has sunk in, especially when you get away from the big hubs, so what you will start to see in Asia is the awakening of their image, rather than ours.

For instance, the Topper, fine bit of British engineering, spearheaded by a British ex-Topper class president, who happened to be seconded to China, so China brought 2-3,000 of them 15 years ago.   Don't think they have brought any more, and highly unlikely they will buy any more or RS or Bic or anything like that.

They are becoming far more pragmatic, just because it's "good" in Europe or US dose not mean it will be good in Asia.    And South America is similar.

The Starboards, or the Element6 will have a influence, Element6 more so because of the fluency of the staff in multiple Asian languages (I'm talking the British and American owners) and the ease of logistics with Thailand and the rest of Asia, but there will be a lot of home growth products out of every Asian country, and those products will be very cost effective.    China is the powerhouse, (but India will be very interesting) WRT Asia, just like Brazil is in South America, USA is in Nth America, and South Africa is/was in Sth Africa.

~~~~~~~~~~~~~~~~~~~~

With respect to lbs/ft-sq or in my case kgs/m-sq,

49er is about 119kgs/m-sq,   89er and Vivace are both close to 112kgs/m-sq, interestingly the 29er is up around 136kgs/m-sq and the 470 is way down around 77kgs/m-sq.    All of those numbers are fudges and I can do the 470, because I designed one some years back, so I have the files, no other reason.

This is at what I believe is standard break out attitude and speeds which vary because of changes in HS

But that is not the whole story, the other big factor is power to weight ratio, 29er is about 89%, 49er is 149%, 89er will be very close to 1 (100%, so same RM (kg/m) as weight) and a 470 is about 67%

so a 29er will stay in the water longer, and that is for 2 reasons, a) it's safer for the kids, it's not quite as frisky as say a 49er and b) it's quite possibly a better hull shape given what we know now.  (and it's higher panel loading is possibly why it can achieve higher speeds than a 49er), where as a 49er comes out early simply because it got so much grunt, it just blasts over its bow wave.   But the 89er, it's a displacement toy (80% of the time) and it has the advances of the 29er (hull design) so I expect to to stay in the water all the time upwind, but it also has lot's of potential grunt so I want it to come out effortlessly off the wind.

I do expect to occasionally (quite rarely) do mid 20's in the 89er but to design for that would be rather stupid, and it's possibly 0.001% of the time.   But, as said, it will have plenty of grunt, so I do want it to pop up on the plane effortlessly when we turn the corner at the top mark and play AWA's down hill.

The reality is that, sure I think we have advanced the shape, but Vivace was such a good role model, why wouldn't I just duplicate it's numbers (so I did)!

Cultural blindness isn’t exactly an American fiefdom, but we have had our moments.  The archeology and anthropology of sailing are invaluable, but while trying to overcome the inertia of cultural palm gazing is an almost impossible task, some enlightenment (or reality) oozes around the edges.  I started in the American piano industry in the 60’s, and witnessed first hand it’s stubborn self destruction- going from 100’s of vibrant companies to 2 or 3.  I also watched and represented technically and artistically 15 brands from around the world, and watched the flourishing of different approaches of craft influencing mechanization based on a discarded (here) American industrial concept (Demming). It has come full circle (kind of) back here, but the same forces that make it impossible to deal with COVID here have been at work in so many endeavors that rational creativity has been drowned by the shouting.  Thank God, in sailing, some of us live on the West Coast, and have embraced Oceania and run with it, Like Hobie Alter, for example, along with Windsurfing, surfing, kayaking, surf skis, SUP’s etc.  Whether mass industrialization is the path forward is kind of up in the air, I think, and Yamaha buying into Bosendorfer may fit into that scenario, as well as the Clark foam implosion,  as the bespoke movement chugs along.  Personally, I believe nimble small to medium production is the future.  Man made products along with more green, like wood.  Like right now, I have a handmade German wood cello, a Czechoslovakian electric cello, an American electric, and an American carbon cello. These three approaches are all starting to combine.  Same in pianos.  And culturally idiosyncratic pianos are once again peeking out around the world- Australia is a good example.  While the mass manufacturers thunder along, gobbling each other up.  So, as you imply, regional markets may be the future, with some leakage globally among those with some curiosity.  Will the basic scientific principles survive?  It’s starting to fray here, big time. Lord, in his book that I posted deals with that inertia, which is wonderful, much as your dad did.

My personal Big Question is whether the effect of rules (which are in their nature cultural)  on sailboats is stifling things, or defining progress.  The power of limits is a real thing, and the next big thing could be the result of a different rule, from a different point of view.  But, was the Laser the product of a rule?  Windsurfing? Kiting? Sportsboats? Multihulls? 49er? It gets back to the fundamental logic of Demming’s idea of production in many ways, and the way it fits into a culture.  

  • Like 1
Link to post
Share on other sites
5 hours ago, JulianB said:

But that is not the whole story, the other big factor is power to weight ratio, 29er is about 89%, 49er is 149%, 89er will be very close to 1 (100%, so same RM (kg/m) as weight) and a 470 is about 67%

so a 29er will stay in the water longer, and that is for 2 reasons, a) it's safer for the kids, it's not quite as frisky as say a 49er and b) it's quite possibly a better hull shape given what we know now.  (and it's higher panel loading is possibly why it can achieve higher speeds than a 49er), where as a 49er comes out early simply because it got so much grunt, it just blasts over its bow wave.   But the 89er, it's a displacement toy (80% of the time) and it has the advances of the 29er (hull design) so I expect to to stay in the water all the time upwind, but it also has lot's of potential grunt so I want it to come out effortlessly off the wind.

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

Edited by Sidecar
  • Like 1
Link to post
Share on other sites
3 hours ago, Sidecar said:

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

Which could be one reason some proa cultures used a solid log for the small hull?  

Link to post
Share on other sites
4 hours ago, Sidecar said:

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

This is fun. So, quick and dirty numbers for Amati

Loading somewhere between 44-52 lbs/sq ft (214- 253 kg/m squared? So I’m under your magic number)), beam/ length .25 - .27.  I don’t know if dynamic length means anything in this context.  I do know when I stand on the bow, the stern flow gets real smooooth

 We do have a rooster tail. Aaack!

This puts us at the low end of loading in Lindsay Lord land, but in the ball park.  We reached our top speed (22 k) in a 3-4 foot chop, which Lord would predict. Downwind we do not go airborne, and control is not a problem.  Once we hit about 11 knots she gets more stable as we go faster. And she’s really close winded- like a meter boat.  Maybe that’s the trade off?  The only time she jumps is when we’re going upwind in more than 10 knots in lumpy stuff.

Our bow stays close to the water.  Looks like I wanted a cruising sled & I got one!

I’ll try to figure the leverage later.

Link to post
Share on other sites
6 hours ago, Amati said:

Cultural blindness isn’t exactly an American fiefdom, but we have had our moments.  The archeology and anthropology of sailing are invaluable, but while trying to overcome the inertia of cultural palm gazing is an almost impossible task, some enlightenment (or reality) oozes around the edges.  I started in the American piano industry in the 60’s, and witnessed first hand it’s stubborn self destruction- going from 100’s of vibrant companies to 2 or 3.  I also watched and represented technically and artistically 15 brands from around the world, and watched the flourishing of different approaches of craft influencing mechanization based on a discarded (here) American industrial concept (Demming). It has come full circle (kind of) back here, but the same forces that make it impossible to deal with COVID here have been at work in so many endeavors that rational creativity has been drowned by the shouting.  Thank God, in sailing, some of us live on the West Coast, and have embraced Oceania and run with it, Like Hobie Alter, for example, along with Windsurfing, surfing, kayaking, surf skis, SUP’s etc.  Whether mass industrialization is the path forward is kind of up in the air, I think, and Yamaha buying into Bosendorfer may fit into that scenario, as well as the Clark foam implosion,  as the bespoke movement chugs along.  Personally, I believe nimble small to medium production is the future.  Man made products along with more green, like wood.  Like right now, I have a handmade German wood cello, a Czechoslovakian electric cello, an American electric, and an American carbon cello. These three approaches are all starting to combine.  Same in pianos.  And culturally idiosyncratic pianos are once again peeking out around the world- Australia is a good example.  While the mass manufacturers thunder along, gobbling each other up.  So, as you imply, regional markets may be the future, with some leakage globally among those with some curiosity.  Will the basic scientific principles survive?  It’s starting to fray here, big time. Lord, in his book that I posted deals with that inertia, which is wonderful, much as your dad did.

My personal Big Question is whether the effect of rules (which are in their nature cultural)  on sailboats is stifling things, or defining progress.  The power of limits is a real thing, and the next big thing could be the result of a different rule, from a different point of view.  But, was the Laser the product of a rule?  Windsurfing? Kiting? Sportsboats? Multihulls? 49er? It gets back to the fundamental logic of Demming’s idea of production in many ways, and the way it fits into a culture.  

So I thought the demise of the light aircraft industry was due to litigation in the US??????

I have flown lots of light (power) planes but my passion was gliding, and I love my time soaring, but in some ways I have ticked that off, very likely prematurely.

This is very off thread, so you comments re cello out of wood and Carbon need so time to process.

You comments re rules, that could be a whole additional string, but let me ponder both and come back to you with my ideas, for what it's worth!

                jB

 

Link to post
Share on other sites
4 hours ago, Sidecar said:

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

Have never looked at this, but let me do so and come back to you probably tomorrow, my beer can racing day!  (day off)

  • Like 1
Link to post
Share on other sites
36 minutes ago, JulianB said:

So I thought the demise of the light aircraft industry was due to litigation in the US??????

I have flown lots of light (power) planes but my passion was gliding, and I love my time soaring, but in some ways I have ticked that off, very likely prematurely.

This is very off thread, so you comments re cello out of wood and Carbon need so time to process.

You comments re rules, that could be a whole additional string, but let me ponder both and come back to you with my ideas, for what it's worth!

                jB

 

I get carried away by thinking people.

Link to post
Share on other sites
5 hours ago, Sidecar said:

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

So at 1 degree, we’re .09%, and at 30 degrees we're 2.18.  

Link to post
Share on other sites
2 hours ago, Amati said:

 I don’t know if dynamic length means anything in this context.

It does.

For an indication of dynamic length try halving the length from bow to B w/l max and adding it to length aft of B w/max. Refer to  Figure 4 in the Lord literature. Which is where the long fine bows/entry on Julian’s boats could help, because for the same planing area, they “artificially” improve the B/L ratio, whist still being good in displacement mode. There are a few other subtle things about the ‘9’er boats, which get the tick from Lord as well.

But if your bow doesn’t lift, there is no reduction of frictional area which comes with planing.

Edited by Sidecar
Link to post
Share on other sites
6 hours ago, Sidecar said:

It does.

For an indication of dynamic length try halving the length from bow to B w/l max and adding it to length aft of B w/max. Refer to  Figure 4 in the Lord literature. Which is where the long fine bows/entry on Julian’s boats could help, because for the same planing area, they “artificially” improve the B/L ratio, whist still being good in displacement mode. There are a few other subtle things about the ‘9’er boats, which get the tick from Lord as well.

But if your bow doesn’t lift, there is no reduction of frictional area which comes with planing.

Very thought provoking. Thank you.

Along those lines, what part does rocker profile play with respect to deadrise attitude and the role in planing of Chines which are de-rigeur for 9er family, Mini Transat and Class 40 style scows but absent in the more traditional scows of Melges company products?

Water release and drag reduction is so assisted by the presence of these chines. Leeway resistance is also improved upwind in these and many one metre/Marblehead designs.

  • Like 1
Link to post
Share on other sites

Back on topic, the joy's of fairing, to be honest, it was only 3 hrs (×2) people, so not that bad.   Gelcoat tomorrow morning to seal the plug, Thursday prep, Friday hopefully 1/2 a hull.   22kgs of foam btw amount other bits a pieces, probably a 4 hour (×4 people) layup.20211123_161929.thumb.jpg.35bb866c7e793121ac54bbfcd0ab1a3f.jpg

Chines, lots and lots of data going back to the early 70's.

Tomorrow, jB

  • Like 4
Link to post
Share on other sites
16 hours ago, Sidecar said:

It does.

For an indication of dynamic length try halving the length from bow to B w/l max and adding it to length aft of B w/max. Refer to  Figure 4 in the Lord literature. Which is where the long fine bows/entry on Julian’s boats could help, because for the same planing area, they “artificially” improve the B/L ratio, whist still being good in displacement mode. There are a few other subtle things about the ‘9’er boats, which get the tick from Lord as well.

But if your bow doesn’t lift, there is no reduction of frictional area which comes with planing.

I meant excessive bow up angle.  Julian’s right.  Maybe another thread for this really cool drift??  (It is the problem with building/working on a boat- everybody stops by to gab.  Ask me how I know…. On the other hand, if Julian doesn’t mind?  It’s his show.:))

Link to post
Share on other sites
3 hours ago, JulianB said:

Back on topic, the joy's of fairing, to be honest, it was only 3 hrs (×2) people, so not that bad.   Gelcoat tomorrow morning to seal the plug, Thursday prep, Friday hopefully 1/2 a hull.   22kgs of foam btw amount other bits a pieces, probably a 4 hour (×4 people) layup.20211123_161929.thumb.jpg.35bb866c7e793121ac54bbfcd0ab1a3f.jpg

Chines, lots and lots of data going back to the early 70's.

Tomorrow, jB

Fairing involves the same precautions as public health- masking and cleaning up :lol:

Link to post
Share on other sites
23 hours ago, Sidecar said:

So to be clear, power to weight ratio is: RM/ Displ.

Waterline beam (lifting edge) relative to length is also a big factor in facilitating planing. Just guessing, but the 29’er and 49’er both would have a B/L length of ~ 33%, and the 89’er would be ~ 24%? Interestingly, the Lindsay Lord literature above suggests that the practical sweet spot for planing boats is ~ 35 to 40%, with a big drop off in efficiency, as the %age goes down, certainly below 20%.

FWIW, He also says that you can be under loaded panel wise and still be not as fast as a boat with higher panel loads, because of loss of control.

 

Pogo 30’s in the Lord sweet spot?  Dehler 30 OD?  Weight wise.  Ocean going then? In protected water, the 89er would probably be doing a horizon job. Horses for courses?  How bumpy is too bumpy?  The 89er shape is tres cool, and the -er family does well in waves.  Used to love the Taser upwind in a chop- almost spooky how smooth and quiet she was.  89er will be similar?  

  • Like 1
Link to post
Share on other sites
16 hours ago, Boink said:

Along those lines, what part does rocker profile play with respect to deadrise attitude and the role in planing of Chines which are de-rigeur for 9er family, Mini Transat and Class 40 style scows but absent in the more traditional scows of Melges company products?

Water release and drag reduction is so assisted by the presence of these chines. Leeway resistance is also improved upwind in these and many one metre/Marblehead designs.

If a boat was in planing mode all the time, eg powerboats, there would be no rocker in the back half of the boat and dead rise would be as little as possible and most importantly, constant dead rise with no sectional shape change. Dead rise and width/length of planing section being determined by sea state and required operating speed. Yachts by comparison, have limited power and can’t be kept at the optimum/max design speed  and trim or even kept level all the time, so need to make compromises on these principles to be all round fast. Rocker and slightly curved aft bottom sections are part of that compromise, which helps to smooth out transitional changes and also help to make the boat inherently stronger/stiffer, which can help lighten its structure. The ‘9’er range of boats do rather well on that score.

There are any number of efficient fast round bilged boats, including the Melges scows you mentioned, which plane really well, but chines do seem to confer advantages if used well.

They can increase the effective planing area available for a given width or beam. The sections of chines just above the water surface can/should act as spray deflectors, reducing frictional surface area and recycling as much of the energy as possible generated from pushing water aside, whilst helping to keep the boat “dry”. They can help with directional stability and inherent leeway resistance, and they can help stiffen boat structures and make them easier to build.

Contrary to what I posted earlier about B/L ratios, there are any number of boats which are under 20% which plane extremely well, Flying fifteens and again Melges scows are classic examples. Another, which breaks even more planing “rules” is the International 10m2 Canoe.

With regard to Mini 6.5 and Class40 scows, as fast as they may be, I reckon they are bastardised by the bow and hull sectional restrictions placed upon them. I think that there is a lot more potential to come from scows yet. You just have to look at Hickman Sleds and tunnel hulls to see all sorts of possibilities. Without similar restrictions, there is no doubt in my mind that even the AC75 foilers would have ended up with full on scows fuselages.

Very little under the sun hasn’t been done or thought of before. We are in exciting times, because of the new materials now available and the huge increased strength and weight reductions we can achieve, it means that there are a lot of new possibilities and even old ones which perhaps should be revisited.

 

 

00DE436F-1692-487B-B727-B5E30FEA1726.jpeg

  • Like 2
Link to post
Share on other sites

Just so it's understood, this is a plug, tomorrow is a full day of prep, knocking of the hi spots, 3 coats of wax, then perforated plastic, peel ply.  Then pre cut unies (basalt) and then pre cut bags, suction strip, spiral tube, yad yad yad.

Friday start early, probably 4hrs x 4 people, inner layer and thick core (P80) all sucked down, 6hr cook.

Saturday, 7 Islands Race, big few days.

  • Like 2
Link to post
Share on other sites
On 11/23/2021 at 6:57 AM, JulianB said:

So I thought the demise of the light aircraft industry was due to litigation in the US??????

I have flown lots of light (power) planes but my passion was gliding, and I love my time soaring, but in some ways I have ticked that off, very likely prematurely.

This is very off thread, so you comments re cello out of wood and Carbon need so time to process.

You comments re rules, that could be a whole additional string, but let me ponder both and come back to you with my ideas, for what it's worth!

                jB

 

Just circling back, late start today.  

Rules, I remember the late great(s) Ian Bruce and Ward McKim lamenting the "internationalisation" of the Laser class because of the extent that it would be beset by rules and regulations that would tie their hands, and as someone who has to deal with a Int Olympic class and a Int Youth class everyday that is very true.

(Only I have to say the Olympic class is far easier because the actual sailors are making decisions and not parents)

And success is not at all tied to being International, just look at the growth in all the big classes before they were internationalised!

But if you are talking about the far more interesting rules as in conformity as in not shaking the stick to hard, then we are all being moulded by social moral’s and not pressing the boundaries too far, and in some societies that is a far greater motivator than others.

I remember a quite prolific English designer and I having a few DMC [Deep and meaningful Conversations) over a glass of Australian red, and he described most English boats as “puddle ducks” because, and you only need to look at a recent post on SA Dinghies, that a lot of English sailing happens in estuaries and gravel pits. So, boats that can go over tidal flats and tack with very little loss of speed are highly likely to be popular.

LP, RS and Topper have been particularly successful exporting this to the world.   Now you have the French doing it with the Bic, and the codification of the C420 and the FJ in the US that is unlikely to leave that country's borders.

I also have spent time in South Africa, and you see the similarities with Dabchicks and the NZ and Australian Classes.   I was also very lucky to be shown over a US Sandbagger up in Long Island.   The Sandbagger and the Historic 18teen bear a lot of similarities.

My biggest bug bear with most mentors/parents/coaches is that they are obviously comfortable with what they did, they have some expertise in that field and so they actively guide their charges down those paths.

Yet it is exactly those same people who demand the latest tech for themselves.   They would not be seen dead with the old “brick” mobile phone, baseball I understand is now embracing a new bat where the knob on the end of the grip is angled rather than being perpendicular, there are even golf clubs with this new grip, yet they demand that the most tech savvy group in our society use, that are embracing the angled grip or show us how to use this new tech use antiquated sailing equipment and wonder why there are declining numbers.    This same group of mentors/coaches/parents look down on things like multi hulls, foiling and skiff as some short-term aberration.

Then the longer that they hold that line, the further those people fall behind and they wonder why there are no medals.

There is no doubt that there a similarities in Asia, which is far more driven by the risk of losing face, than doing the deal, which seems to be the US pre-occupation, plus they (the Asians) tend to reach out to the Dutch and the Finnish plus a spattering of antipodean designers and boats like the FR28R are beautifully designed, but their fwd. U sections are far more at home on the IJsselmere than on the way out to Double Cone.

Back to practicalities and the 89er, see where that lands.

 

 

  • Like 1
Link to post
Share on other sites

Scillyjosh, couple of points here.

Sure the new CST mast was forced on us.

But the key decisions WRT the sails where all made by a WP generated by the sailors.

My point being that a change of this sort of nature will be made by the sailors.

Now, couple of side notes.

a) already the girls can't sink the hull enough, they are 30kgs lighter approx and the ends come out.    Now this is true of 470 and Laser and the board, but it's probably more noticeable with a boat that planes upwind, because you need all the WL length you can get.

b) if we go green, and we exploit say PET's and Basalt's, plus change the gunwale, yad yad yad, we maybe able to strip another 20 kgs out of the boat and if we do that then the girls will be floating up in the stratosphere and the boys will start to bitch.    So that may be the driver to look at the hull form again.

Then if, (and again it will be the sailors) chose to foil, then the function of the hull changes dramatically, it will become far more aerodynamic, far less hydrodynamic, so that will necessitate an even bigger change.

We came very close to building a new thinner, lighter hull a few years back, but the advancements in PET & Basalt slowed the charge.

Now McMillan and Turner are building OK's out of PET/Basalt as a trial, because they can and use them in racing.    I may start on a "bat-boat" after the 89er which would be a rough thinned down 49er, again using Basalt and PET and have 5-6 other tweaks (inc a few extra c-case to facilitate foiling).     

Then if the sailors so chose, the I49erCA may adopt that and if so, WS would have to also endorse it, so many steps to follow before it can happen.

Link to post
Share on other sites
On 11/23/2021 at 3:28 PM, Boink said:

Very thought provoking. Thank you.

Along those lines, what part does rocker profile play with respect to deadrise attitude and the role in planing of Chines which are de-rigeur for 9er family, Mini Transat and Class 40 style scows but absent in the more traditional scows of Melges company products?

Water release and drag reduction is so assisted by the presence of these chines. Leeway resistance is also improved upwind in these and many one metre/Marblehead designs.

Hi again Boink.

If you are going to sail a boat that will plane down wind, then really Chines are essential.   Sure you can get away without them, like the Laser, but that's also why you’re top speed is likely to be limited to 17knts, the faster you go in a Laser, the more you get sucked down into the water by the "turn of the bilge.   You only need to do the spoon experiment with the tap in your kitchen to prove that.

That also lets me digress to an experiment I did, very likely in Montreal or Kingston (Canada) in 1977 where we used Poly-go-blue and Canadian Starbrite and artificially generated a “water separation line” on a un-whitting Canuk and his Laser. The result was so demonstrably blatant that Ian (Bruce) insisted that I bury it.      What we effectively did was generate a chine, in a round bilge boat.   And it wasn’t just a bit faster.

All through the late 80’s and into the early 90’s we exploited this on the Primes, and the AAMI’s with what I only could describe as decisive results.

Then you have Barry Johnson (ICM 49er/29er) needing to measure the sharpness of the chines, and the rule was pushed so hard that at some point, the regulation became so absurd and difficult to police that it was abandoned and now 49er chines are as sharp as you dare, 29er are heading that way.   (BTW, < 0.5mm Rad is about enough to ensure you get good separation)

Then a bit like the spoon test, Simon Watin used a hose on a 49er as part of his thesis in 2008.

Sidecar, most 9er boats have dead straight runs aft of the centre-case.    Sailing on 18teen called Entrad (1986)  Goodman Fielder (1987), those boats had a hollow in the keel line aft, really fast when you went over 17-18 knts.   You will find them on the step of the old Sunderland’s and Solent’s that dad flew, but you have that photo in dad’s book (Entrad in Auckland) in full flight.   The quid pro quo, but bit like screwing your whole design process to something that may happen only 1% of the time, it punishes you in sub 17knts and that has to be 99% of the time.

So with a bit of fiddling, and I really think this is what has made the really big differences in the last say 10 years is we have understood and been able to blend the fine fore-foots (in front of the centre-case) which are fundamental for upwind performance with the planning after-body which is so important for speed once you turn the corner.

Obviously there is a lot of nuance in going from a wave carving, very low wave impact and very little lift front ½ of the boat, to a get up and go aft ½ of the boat, without trying to be a master of everything but failing miserably in both.

Possibly the biggest thing is to abandon the premise that fwd U sections will lift the bow earlier, and rely on, and have confidence that the aft sections that will suck the transom down and in doing that, ensure that you never rely on the bow to hold the nose up/out.

That in turn allows you to keep the front really fine, so when you inevitably plunge, may get some green stuff over the bow, but you never nosedive, or I never did.

The current flock of 18teen have very full bows, and you see them going around leaping feet/meters out of the water, and they occasionally plunge and then do the full cartwheel, very spectacular.     The 18teen of the 90’s, bow’s lifted ½ m max, and yes plenty of green stuff, but full cartwheel could be counted on one hand over a 10 year period.

Pretty obviously if we ever cartwheel the 89er, I’m sure you will all know about it before any of us hit the water.

  • Like 1
Link to post
Share on other sites
2 hours ago, JulianB said:

So with a bit of fiddling, and I really think this is what has made the really big differences in the last say 10 years is we have understood and been able to blend the fine fore-foots (in front of the centre-case) which are fundamental for upwind performance with the planning after-body which is so important for speed once you turn the corner.

I knew that ‘9’er runs aft were pretty straight and without twist, which is good. I also like the constant curve (arc?) aft cross section bottoms, which can accommodate variations in roll (heel) and yaw with minimum added resistance. I am not keen on hollow keel lines aft and will follow Verdier’s latest Class40 scows with interest. See below.

Probably another advantage of the fine bows and hard chines aft approach is the greater inherent lateral resistance and directional stability contribution by the hull, especially in the ends, which means you can get away with smaller centreboards, which means less WSA and frontal area resistance. As evidenced by the surprisingly small foil proposed for the 89’er.

Using big flares aft, apart from RM, help to increase the chine’s efficiency, and probably provide a little dynamic RM if you inadvertently heel too much?

 

32AD1AB2-F156-47BA-B403-3C0ACA864E47.png
PS:

For those interested in an easy (simplified) overview of planing boats, Dave Gerr’s book “The Nature of Boats” chapters 18 “Reading Between the Lines” and 19 “Speaking Volumes” are helpful.

  • Like 1
Link to post
Share on other sites
10 hours ago, Sidecar said:

I knew that ‘9’er runs aft were pretty straight and without twist, which is good. I also like the constant curve (arc?) aft cross section bottoms, which can accommodate variations in roll (heel) and yaw with minimum added resistance. I am not keen on hollow keel lines aft and will follow Verdier’s latest Class40 scows with interest. See below.

Probably another advantage of the fine bows and hard chines aft approach is the greater inherent lateral resistance and directional stability contribution by the hull, especially in the ends, which means you can get away with smaller centreboards, which means less WSA and frontal area resistance. As evidenced by the surprisingly small foil proposed for the 89’er.

Using big flares aft, apart from RM, help to increase the chine’s efficiency, and probably provide a little dynamic RM if you inadvertently heel too much?

 

32AD1AB2-F156-47BA-B403-3C0ACA864E47.png
PS:

For those interested in an easy (simplified) overview of planing boats, Dave Gerr’s book “The Nature of Boats” chapters 18 “Reading Between the Lines” and 19 “Speaking Volumes” are helpful.

just went hunting, http://earwigoagin.blogspot.com/2018/03/two-different-scows-at-inverloch.html

It shows a A12, possibly me sailing (black and white photos), it's definitly NSC.

This concept has dead flat pannels, be very interesting to play with it.

                     jB

Link to post
Share on other sites
On 11/22/2021 at 8:28 PM, Boink said:

Very thought provoking. Thank you.

Along those lines, what part does rocker profile play with respect to deadrise attitude and the role in planing of Chines which are de-rigeur for 9er family, Mini Transat and Class 40 style scows but absent in the more traditional scows of Melges company products?

Water release and drag reduction is so assisted by the presence of these chines. Leeway resistance is also improved upwind in these and many one metre/Marblehead designs.

FWIW, here are some pics of a scale model with plywood thickness = 1/4” (Gougeon) IIRR I did 9 years ago when I was messing with tortured ply sailing canoes.  It’s pretty beat up, as I tossed it around in our 22’ koi pond. It was really stable in smooth or wavy conditions.  Didn’t seem to get stopped by waves. The shape is what happened by itself when I glued the bows together.  The keel tape fell off a while back.  I know, the bow is warped. But the bow was a ways in the air when planing

20B68801-A269-4BC1-A0D2-9B1304334EA1.jpeg

A1B77C84-BAC4-4B19-9EFA-879873DCBCF4.jpeg

0186F5BD-4D92-454C-A9B6-8059AC138CCC.jpeg

Link to post
Share on other sites
1 hour ago, Varan said:

Y'all really need to pause for a moment and enjoy a beer. 

[email protected] awesome video though...

We where infact very luck, it was only 16c, so the epoxy was slow.

It was 5 hrs, start to vacuum, and even the C-case and the Rudder gudgeon where still plyable.   Unfortunatly I could only get 0.6bar, would have liked 0.8, but shit happens, and as we lifted the temp (under vacuum) to 45 and then to almost 60c, it all went soft and things like the centercase, all bedded down near perfcetly.

We basically started in ernest at 08:30, and we pulled vacuum about 13:30, and I stayed on heater/fire watch till 19:00, when even the epoxy at 16c had gone hard.

Monday will be some detail work with a power plane, just one of the really cheap $100 units, likely to only be used once for 2 hrs, but in the right hands, invaluable.

By the end of the week, hopefully we wil have the outer skin on, leave it harden up for 2-3 days then flip it up-right and into framing and the alike.

Looks like there may now be 2 or even 3 sister ships, I just hope that those people who are putting faith in me, that it dose not disapoint!

~~~~~~~~~~~~~~~~~

Also been quized over Basalt, so this is my understanding.

Basalt (Russian/Ukraine), the stuff I am using has a MPa of about 480.   (There are effectively 2 grades, the other grade has a MPa of about 320)

Carbon, there are nominally 4 grades, Std, intermediate, Hi-modulus and Ultr-hi-modulus, the MPa ranges from about 500-720, and even though the Ultr-hi has a hi MPa, it infact has a much lower (than std carbon) BS.

E-Glass (E = Electrical as in non conductive) has a MPa around 240-260 and S-Glass (S = Special) has a MPa 320-340.    (Stainless Steel is 240, BTW)

Also just to complicate it further, the Americans speak of MSI (Millions of lbs / Square Inch) and Hi  (approx 42) and Ultra-hi (around 60) are turely astounding.

So the garden variety carbon cloth you buy in Australia from Allex, or SP or Trogan is std carbon.     I am very likely to get a Hi-Modulus Carbon mast, and again, it's numbers are truely austounding, but very much horses for courses.   Using Hi-Mod in a mast means smaller diameter, lighter and lots and lots of side benifits of using that material in a mast, sure it's expensive but I belive very justifiable.

Garden variety Carbon, which is the sort of stuff you would buy and use in a hull, is very close in MPa to the Basalt I am using, but my tests show me that the Baslat is in 99% of the cases that the hull may experience, in-distinguishable from Std Carbon and probably 10 time tougher, so it will handle the inevitable whack against the finger jetty or getting it wrong putting it in the cradle.  

Again I come back to the fact that this boat is about 4-5 fat old bastards out to have some fun, and fun we will have.   I have just come back from doing the 7 Islands Race,  Stanno, wheres my beer????,   Wind got up to 35knts, we did a max of 14knts (Farr 40) but it certianly blew the cobwebs out!

                   jB 

  • Like 4
Link to post
Share on other sites
5 hours ago, JulianB said:

Unfortunatly I could only get 0.6bar, would have liked 0.8, but shit happens,

I did wonder how long it took considering how sped up the video was!
Did you have issues getting the bag absolutely tight, or what was the issue with not getting as high vacuum pressure?

Was pretty great to watch for a noob, so thank you for that.
Also nice to read about basalt since I found a few online sellers in my area that are not that much more expensive than glas and it looks interesting!

Link to post
Share on other sites
3 hours ago, allweather said:

I did wonder how long it took considering how sped up the video was!
Did you have issues getting the bag absolutely tight, or what was the issue with not getting as high vacuum pressure?

Was pretty great to watch for a noob, so thank you for that.
Also nice to read about basalt since I found a few online sellers in my area that are not that much more expensive than glas and it looks interesting!

One of the advantages of glass fibre for beginners is that it is really easy to see if it is fully wetted as it turns transparent. With the likes of carbon and basalt it is a bit more difficult. I recommend using peel ply to suck up the excess.

Link to post
Share on other sites
4 hours ago, neuronz said:

With the likes of carbon and basalt it is a bit more difficult.

It kind of really is compared to glass, personally I always use the guidelines for weight fiber/epoxy and weigh out that much. Usually works for myself, otherwise I'd probably end up using way too much epoxy.

Link to post
Share on other sites
9 hours ago, allweather said:

I did wonder how long it took considering how sped up the video was!
Did you have issues getting the bag absolutely tight, or what was the issue with not getting as high vacuum pressure?

Was pretty great to watch for a noob, so thank you for that.
Also nice to read about basalt since I found a few online sellers in my area that are not that much more expensive than glas and it looks interesting!

Just got to put this into perspective.

A lot of hi end FRP shops limit their vacuum to 0.5 bar, these are hi-end cats, skiffs using all sort of cores from Nomex thought PVC's and PET's.   If you build your boat from plank balsa, as I have done a few times with exceptional results, then you simply can't use any more than about 0.5Bar because you will crush the core, and strip planked balsa is an exceptional core.

So 1 Bar = 1 Atm = 29" (900mm) of Hg (Mercury) = 401”of H²O & = approx. 27lbs/ inch².

So at 0.5 Bar you are pushing on every inch² with a force of 13.5lbs (about 6kgs) so that is the size of you thumb (or my thumb at least).    The 89er is approx. 8.5 x 3.5 = 30m² and that equals approx. 330ft² and that = approx.. 47,500 inch² so that’s = approx. 280 - 300 tone/ton of clamping pressure.  And all of that happens with a $300 vacuum pump and mine its 30+ years old and a bit of thin nylon film.

Watching the bag come down and exert this sort of clamp (the technical term is consolidation)  still is awe-inspiring even after 50 years of watching it happen.

Now I have jumped between Imperial and Metric and very likely got some sums wrong, but it really does not matter, we are talking about a vast amount of pressure.

I have stated before I don’t like to go over 0.8 of a Bar. Major reason for that is you squeeze the laminate dry and strip out solids. (nb1)   If I did that, and with the 18teen before I twigged to this, you had to screed the inner surface with a extra layer of resin, after it had all cured and was de-bagged.

At 0.8Bar, you don’t (have to re-screed). So at 0.6 – 0.65Bar I will still have 350-380 or about 15lbs per inch² clamping pressure and I will be marginally more resin rich but this surface is the inner hull laminate or the “bilge” so if ever there was a place to be resin rich, this is it.

Nb1, there are resins and there are resins.   I am using some stuff called Boatex, I have used it before over 30 years and I have built a larger number of exceptional products from it.    It’s what I would call an industrial product, rather than a retail.   It has no additives, and it’s very stable, so by that I use WEST system when I built my balsa 18teen and those boats lasted 20-+ years, very likely because of the additives, but it’s those additives that can make you hyper sensitive to epoxy.    A very good friend of mine, he sailed with me, still can’t use one brand which I won’t mention even 20 years on because he became allergic to it. Not so with this system, and I am sure there are others.

The other advantage of Boatex that seems relevant is it dose not suck dry, it’s quite thick, and very stable, (at 16-20c) then lift the temp to 45-60c, it becomes far less viscous so it flows on it’s way to curing.    And finally, post cure, putting it in the Australian sun for a day under tarps, the cure goes right through to completion, so it’s perfect.

I have no doubt there are other systems, and I have tried many and had a lot of success, but other have become allergic while doing that, so this is my old faithful.

For anyone interested, here is the contact.  (and no, there is no commission)

Just got to put this into perspective.

A lot of hi end FRP shops limit their vacuum to 0.5 bar, these are hi-end cats, skiffs using all sort of cores from Nomex thought PVC's and PET's.   If you build your boat from plank balsa, as I have done a few times with exceptional results, then you simply can't use any more than about 0.5Bar because you will crush the core, and strip planked balsa is an exceptional core.

So 1 Bar = 1 Atm = 29" (900mm) of Hg (Mercury) = 401”of H²O & = approx. 27lbs/ inch².

So at 0.5 Bar you are pushing on every inch² with a force of 13.5lbs (about 6kgs) so that is the size of you thumb (or my thumb at least).    The 89er is approx. 8.5 x 3.5 = 30m² and that equals approx. 330ft² and that = approx.. 47,500 inch² so that’s = approx. 280 - 300 tone/ton of clamping pressure.  And all of that happens with a $300 vacuum pump and mine its 30+ years old and a bit of thin nylon film.

Watching the bag come down and exert this sort of clamp (the technical term is consolidation)  still is awe-inspiring even after 50 years of watching it happen.

Now I have jumped between Imperial and Metric and very likely got some sums wrong, but it really does not matter, we are talking about a vast amount of pressure.

I have stated before I don’t like to go over 0.8 of a Bar. Major reason for that is you squeeze the laminate dry and strip out solids. (nb1)   If I did that, and with the 18teen before I twigged to this, you had to screed the inner surface with a extra layer of resin, after it had all cured and was de-bagged.

At 0.8Bar, you don’t (have to re-screed). So at 0.6 – 0.65Bar I will still have 350-380 or about 15lbs per inch² clamping pressure and I will be marginally more resin rich but this surface is the inner hull laminate or the “bilge” so if ever there was a place to be resin rich, this is it.

Nb1, there are resins and there are resins.   I am using some stuff called Boatex, I have used it before over 30 years and I have built a larger number of exceptional products from it.    It’s what I would call an industrial product, rather than a retail.   It has no additives, and it’s very stable, so by that I use WEST system when I built my balsa 18teen and those boats lasted 20-+ years, very likely because of the additives, but it’s those additives that can make you hyper sensitive to epoxy.    A very good friend of mine, he sailed with me, still can’t use one brand which I won’t mention even 20 years on because he became allergic to it. Not so with this system, and I am sure there are others.

The other advantage of Boatex that seems relevant is it dose not suck dry, it’s quite thick, and very stable, (at 16-20c) then lift the temp to 45-60c, it becomes far less viscous so it flows on it’s way to curing.    And finally, post cure, putting it in the Australian sun for a day under tarps, the cure goes right through to completion, so it’s perfect.

I have no doubt there are other systems, and I have tried many and had a lot of success, but other have become allergic while doing that, so this is my old faithful.

For anyone interested, here is the contact.  (and no, there is no commission)

Just got to put this into perspective.

A lot of hi end FRP shops limit their vacuum to 0.5 bar, these are hi-end cats, skiffs using all sort of cores from Nomex thought PVC's and PET's.   If you build your boat from plank balsa, as I have done a few times with exceptional results, then you simply can't use any more than about 0.5Bar because you will crush the core, and strip planked balsa is an exceptional core.

So 1 Bar = 1 Atm = 29" (900mm) of Hg (Mercury) = 401”of H²O & = approx. 27lbs/ inch².

So at 0.5 Bar you are pushing on every inch² with a force of 13.5lbs (about 6kgs) so that is the size of you thumb (or my thumb at least).    The 89er is approx. 8.5 x 3.5 = 30m² and that equals approx. 330ft² and that = approx.. 47,500 inch² so that’s = approx. 280 - 300 tone/ton of clamping pressure.  And all of that happens with a $300 vacuum pump and mine its 30+ years old and a bit of thin nylon film.

Watching the bag come down and exert this sort of clamp (the technical term is consolidation)  still is awe-inspiring even after 50 years of watching it happen.

Now I have jumped between Imperial and Metric and very likely got some sums wrong, but it really does not matter, we are talking about a vast amount of pressure.

I have stated before I don’t like to go over 0.8 of a Bar. Major reason for that is you squeeze the laminate dry and strip out solids. (nb1)   If I did that, and with the 18teen before I twigged to this, you had to screed the inner surface with a extra layer of resin, after it had all cured and was de-bagged.

At 0.8Bar, you don’t (have to re-screed). So at 0.6 – 0.65Bar I will still have 350-380 or about 15lbs per inch² clamping pressure and I will be marginally more resin rich but this surface is the inner hull laminate or the “bilge” so if ever there was a place to be resin rich, this is it.

Nb1, there are resins and there are resins.   I am using some stuff called Boatex, I have used it before over 30 years and I have built a larger number of exceptional products from it.    It’s what I would call an industrial product, rather than a retail.   It has no additives, and it’s very stable, so by that I use WEST system when I built my balsa 18teen and those boats lasted 20+ years, very likely because of the additives, but it’s those additives that can make you hyper sensitive to epoxy.    A very good friend of mine, he sailed with me, still can’t use one brand which I won’t mention even 20 years on because he became allergic to it. Not so with this system, and I am sure there are others.

The other advantage of Boatex that seems relevant is it dose not suck dry, it’s quite thick, and very stable, (at 16-20c) then lift the temp to 45-60c, it becomes far less viscous so it flows on it’s way to curing.    And finally, post cure, putting it in the Australian sun for a day under tarps, the cure goes right through to completion, so it’s perfect.

I have no doubt there are other systems, and I have tried many and had a lot of success, but other have become allergic while doing that, so this is my old faithful.

For anyone interested, here is the contact.  (and no, there is no commission)

 

image.png

  • Like 2
Link to post
Share on other sites
8 hours ago, neuronz said:

One of the advantages of glass fibre for beginners is that it is really easy to see if it is fully wetted as it turns transparent. With the likes of carbon and basalt it is a bit more difficult. I recommend using peel ply to suck up the excess.

From my POV, you can see any fibre as it wets out, be it Carbon, Aramid, Basalt or Glass, the surface changes appearance.

We did have Peel ply on top of the perforated plastic, and we will remove that “surgically” as we put in frames and the alike but leave the rest until the last moment because it keeps everything clean.

But Peel-ply is 100% single shot, you can’t re use it, plus its $7/m², 30m² = $200+ for what!?
In this instance it offers no advantage on the outer surface of the inner foam.

(BTW, you get to re-use the vacuum bag at least 3-4 times, as is, and then we cut it down to build other parts of the boats, so we could get up to 10 re-cycles out of it.   The perforated plastic, (light blue film) re-use is almost unlimited re-cyclable, and then it has other functions.   Vacuum transfer medium, the final layer, so when we suck the final layer of Basalt and S-Glass to the 3.5mm P115 PET foam (nb1) ) we will do the full catastrophe, so Peel-ply, perforated plastic and then vacuum transfer medium, but we have found a very good crape-paper medium and we then use old CSM and Glass cloth a major pathways, the idea being that with P80 foam you need a pathway every 300mm, (so 600mm between tracks) with P 115 foam, every 200mm and when you come down to the final layer, you need to come right down to about 50mm, so you may as well go right over it.   And allweather touch on it, if you use the right ratio of resin to cloth then there is very little excess.   You see us using squeegee’s,   Alex uses a relatively flexible rubber one, I use a far more ridged plastic one and you get very good at being able to regulate the amount of resin and latter bog/slurry that goes down.   Plus there are holes every 25mm that the resin/slurry fills, so you end up with lot, literally millions of resin pillars.   So what excess that is ends up moving about the laminate so using peel-ply here is just being an environmental vandal and a bit pointless)

It's just me being a bit green and even in the 49ers, we don’t peel-ply the foam suck, in fact in that case they are silicon bags so they quite literally gets 100-150 sucks from a single film.

The finally inner layer (49er so on the inside) uses a really thin Peel-ply – perforated plastic and some vacuum medium, (discarded “dry” glass cloth down in the keel) but the amount of excess resin is down around 4-5% and most of that is in the peel-ply.

Nb1, next stage is to test the foam bond, we do that by scraping a largish coin (in Australia we use a 20c piece) over the surface, and we acoustically can hear the voids.   I would expect maybe 4-8 that we will drill holes and inject slurry (using a syringe), then a we also need to build on probably 200mm of foam on the bow, and fill the inevitable voids with foam and bog.    Then a fair, with a power-plane and torture board. We will tie in a few extra fastening, like the bob-stay anchor, need to point to pull it up onto the trailer, and finish off the lower rudder gudgeon.  Then we will suck on 3.5mm P115 foam.  The truth is surface tension will virtually suck this foam (3.5mm) in place, but we will help it with 250-350 tone of vacuum consolidation.  Then bog, allow to cure and a final fair, then the final layers of 320gm Twill Basalt, and 200gm Crowsfoot weave S-Glass, very possibly at 45-45° as stated before with the full catastrophe.

Some of you have asked for a recomendation on Basalt, after my research I found www.basaltft.com for what its worth!

                    jB

  • Like 1
Link to post
Share on other sites

Thank you for your insight Julian, I had not run the numbers for the foam and missed why you'd be fine with slightly lower vacuum.
Makes sense now that you put it in relation with what you have(imperial unit wizardry or not)

I need to see if that epoxy is available in my area, or something equivalent to it.(well, and just check the jugs I have right now) Last project I messed up ventilation and was somewhat miserable the next day...

Also, always like to hear about any tricks when it comes to reduce and reuse, that is the one thing about bagging/infusion that isn't quite as neat as the rest of the process. Good to hear that perforated film can be reused.(did it sometimes, sometimes not and wasn't sure)

Link to post
Share on other sites
3 hours ago, allweather said:

Thank you for your insight Julian, I had not run the numbers for the foam and missed why you'd be fine with slightly lower vacuum.
Makes sense now that you put it in relation with what you have(imperial unit wizardry or not)

I need to see if that epoxy is available in my area, or something equivalent to it.(well, and just check the jugs I have right now) Last project I messed up ventilation and was somewhat miserable the next day...

Also, always like to hear about any tricks when it comes to reduce and reuse, that is the one thing about bagging/infusion that isn't quite as neat as the rest of the process. Good to hear that perforated film can be reused.(did it sometimes, sometimes not and wasn't sure)

I second that on the reduce and reuse advice. I hate all of the waste that comes with the marine industry and I'm interested in technologies that allow us to reuse as much of the material as possible. I'm encouraged to see how many times you reuse the bagging material. @JulianB I'd love a write up on your experience with the green approach to boat building. 

Link to post
Share on other sites
4 hours ago, allweather said:

Thank you for your insight Julian, I had not run the numbers for the foam and missed why you'd be fine with slightly lower vacuum.
Makes sense now that you put it in relation with what you have(imperial unit wizardry or not)

I need to see if that epoxy is available in my area, or something equivalent to it.(well, and just check the jugs I have right now) Last project I messed up ventilation and was somewhat miserable the next day...

Also, always like to hear about any tricks when it comes to reduce and reuse, that is the one thing about bagging/infusion that isn't quite as neat as the rest of the process. Good to hear that perforated film can be reused.(did it sometimes, sometimes not and wasn't sure)

Just to make sure we are not at cross-purposes (again), my recommendation was aimed at @allweather since he called himself a noob.

Concerning the discussion on vacuum pressure, if I recall correctly Steve Killing once said that while they were building parts for a C-class they discovered that parts done in an autoclave came out less stiff than vacuum parts, because the increased pressure reduced the cross section. So more is definitely not always better.

Link to post
Share on other sites
1 hour ago, WCB said:

I second that on the reduce and reuse advice. I hate all of the waste that comes with the marine industry and I'm interested in technologies that allow us to reuse as much of the material as possible. I'm encouraged to see how many times you reuse the bagging material. @JulianB I'd love a write up on your experience with the green approach to boat building. 

It's a super busy week, I'm going to be all over the place, so you all may have to digest whats there and with any luck, maybe Thursday or Friday!

  • Like 2
Link to post
Share on other sites
12 minutes ago, neuronz said:

Just to make sure we are not at cross-purposes (again), my recommendation was aimed at @allweather since he called himself a noob.

Concerning the discussion on vacuum pressure, if I recall correctly Steve Killing once said that while they were building parts for a C-class they discovered that parts done in an autoclave came out less stiff than vacuum parts, because the increased pressure reduced the cross section. So more is definitely not always better.

Agreed, same with rig height, foil length, even Woody, was reefing his 3rd rig last weekend, not because it was too fresh, just because it was quicker!

Link to post
Share on other sites
6 minutes ago, JulianB said:

It's a super busy week, I'm going to be all over the place, so you all may have to digest whats there and with any luck, maybe Thursday or Friday!

Absolutely can wait...and I appreciate what you've already offered. I am most looking forward to seeing how the boat progresses.

  • Like 1
Link to post
Share on other sites

MPa = Mega Pascals.

The one thing I don't like about Si units is you have to know what a Pascal is, sure he was a pretty smart guy, but that dose not help

A MPa = 1 Newton/mm²  (Nmm²),  now you have to go find what a Newton is, and a Newton is not a thing its a force so it Nm² or someting like that.

This is where my eyes glaze over, I'm sure it's very simply, if you had been born 30 years after I had, and I also had the added disavantage of always having a father who is extremly fluent in BTU, and Radians and Lbs/ft and had no problem doing extremely length calculations (even on excel) in Imperial mesurments.

So the short answer is I belive it could be Kgs/mm², but I am anything but sure.

What I am sure about is the bigger the number, the stiffer and stronger the material in all but a few cases (such as ultra-hi-modulous Carbon).

What I also do, is not believe anything anyone says (inc me) unless I have done a emperical test, or unless I have experienced a result.

If you are comparing say std Carbon at say a MPa of 520 to say Basalt with a MPa of 480 in something like a laminate of the boat, given the highly likely probability that there will be excessive material anyway, I doubt you would be able to register a variation.

If you are using it in a mast of a fin, sure, so you need to add a bit more basalt.    So if you have 4 layers of Carbon, same width and weight as the corrosponding Basalt it should be as simple as saying 4 x 520 = 2080,   Then 2080/480 = 4.33,  so if you added 1/2 a layer, you would exceed the strength/stiffness of the carbon.

And anyone who thinks that is not a good generalisation, please enlighten us all!

                    jB

 

  • Like 1
Link to post
Share on other sites
7 minutes ago, JulianB said:

So the short answer is I belive it could be Kgs/mm², but I am anything but sure.

YES YES YES
Go into a factory in Asia and see if anyone can work out the floor rating which is in Newtons?
( maybe thats why chinese buildings fall down down)
I just unloaded a truck with 5000 newtons on it or was it 5000kg?

My boat cracked as it got hit by a 1000 newton wave..lol

Link to post
Share on other sites
3 hours ago, JulianB said:

you would exceed the strength/stiffness of the carbon.

:D This is what I meant, I couldn‘t quite match your numbers to those I had found for other fabrics. Specifically since tensile strength and stiffness are both measured in Pascal, and then there are the numbers for finished laminate at given fiber/epoxy ratio. 

Anyway, in that case I‘ll do some specific hunting to find basalt with the strength relative carbon you quoted now that I better know which you meant.

As far as stiffness goes I‘ve only seen 10-20% or so greater than eglass and not near carbon‘s over twice as stiff as either! So that was where my initial confusion came from. (Edit: Never mind, shouldn‘t post when tired, just realized that strain is dimensionless)

Do you happen to have the data sheet for the stuff you‘re using?

Link to post
Share on other sites
7 hours ago, allweather said:

:D This is what I meant, I couldn‘t quite match your numbers to those I had found for other fabrics. Specifically since tensile strength and stiffness are both measured in Pascal, and then there are the numbers for finished laminate at given fiber/epoxy ratio. 

Anyway, in that case I‘ll do some specific hunting to find basalt with the strength relative carbon you quoted now that I better know which you meant.

As far as stiffness goes I‘ve only seen 10-20% or so greater than eglass and not near carbon‘s over twice as stiff as either! So that was where my initial confusion came from. (Edit: Never mind, shouldn‘t post when tired, just realized that strain is dimensionless)

Do you happen to have the data sheet for the stuff you‘re using?

www.basaltft.com, it was on the bottom of Sunday's post!  enjoy,  jB

Here the direct link so you don't have to go searching, when your tired, https://www.basaltft.com/pdf/FTW_Technical_Data_Sheet.pdf

Link to post
Share on other sites
3 hours ago, JulianB said:

Here the direct link so you don't have to go searching

:rolleyes: Go me, missing the very visible link you had already posted...
Thank you for pointing that out and relinking.

Interesting that I do find the two grades of fabrics as you've mentioned, but getting the greater strength one in the right weight is going to take some more searching here. Anyway, thanks for the tech talk and now back to boat building.

Link to post
Share on other sites
5 hours ago, allweather said:

:rolleyes: Go me, missing the very visible link you had already posted...
Thank you for pointing that out and relinking.

Interesting that I do find the two grades of fabrics as you've mentioned, but getting the greater strength one in the right weight is going to take some more searching here. Anyway, thanks for the tech talk and now back to boat building.

So it was explained to me that Russia & the Ukraine consider the development and use of Basalt far more seriously than anyone one else. So they want to exploit its use as things like cement reinforcement, use in cars/panels and the alike where as just about everyone else is only really interested in its anti wicking properties which is mostly exploited in FRP tank and pressure vessel making.

So again horses for courses.

If your building water tanks moderate MPa is OK especially given its approx twice std glass.

Wanting non rusting cement reinforcement then higher MPa has its benefits.

  • Like 1
Link to post
Share on other sites
On 11/30/2021 at 6:41 PM, Sailabout said:

Back to the scheduled programme

Any thought to make the 89'er have traps for sportboats events and wings for IRC events?
That would be popular in European lakes and Asia

a) I have already been contact from Switzerland about the possibility, and if you think about it, Trapeeze tend to reduce the loads on a boat, the only increase come from the probably increase in speed.

& b) go back to the mantra, this boat is for 4 fat old bastards, (& 1 young buck) and I have spent more time on trapeeze than I would guess most of you, and I'm not in a rush to go back there.

  • Like 1
Link to post
Share on other sites
6 hours ago, JulianB said:

So it was explained to me that Russia & the Ukraine consider the development and use of Basalt far more seriously than anyone one else. So they want to exploit its use as things like cement reinforcement, use in cars/panels and the alike where as just about everyone else is only really interested in its anti wicking properties which is mostly exploited in FRP tank and pressure vessel making.

So again horses for courses.

If your building water tanks moderate MPa is OK especially given its approx twice std glass.

Wanting non rusting cement reinforcement then higher MPa has its benefits.

Spooky that you should mention the whole pultruded rods and pressure vessel stuff; as just yesterday I was reading about the Arkema's Elium resin which they claim good things for replacing epoxy resin. It has both lower inherent energy production as well as being a reversible and therefore recyclable resin, mainly with an eye on Wind Turbine blade production (which is going to lead to a lot of landfill in the next few years) but referenced both pressure vessels, concrete reinforcement and marine and auto production.

I know Arkema sponsor Lalou Racing and have been instrumental in both Mini Transat 650 and a couple of Multi 50's.

Do you JB have any thought as to the suitability of such resins in high end composite structures (where global rigidity is the aim), bearing in mind your thoughts on Basalt having such impressive MPa properties and whether when combined with PET foam that they would combined competitively against carbon/airex/epoxy type laminates?

Obtaining real world insight as opposed to Technical and Marketing spiel, is not that easy to come by........

Link to post
Share on other sites
11 minutes ago, Boink said:

Spooky that you should mention the whole pultruded rods and pressure vessel stuff; as just yesterday I was reading about the Arkema's Elium resin which they claim good things for replacing epoxy resin. It has both lower inherent energy production as well as being a reversible and therefore recyclable resin, mainly with an eye on Wind Turbine blade production (which is going to lead to a lot of landfill in the next few years) but referenced both pressure vessels, concrete reinforcement and marine and auto production.

I know Arkema sponsor Lalou Racing and have been instrumental in both Mini Transat 650 and a couple of Multi 50's.

Do you JB have any thought as to the suitability of such resins in high end composite structures (where global rigidity is the aim), bearing in mind your thoughts on Basalt having such impressive MPa properties and whether when combined with PET foam that they would combined competitively against carbon/airex/epoxy type laminates?

Obtaining real world insight as opposed to Technical and Marketing spiel, is not that easy to come by........

So Chris Turner  (own's Ovington boats) and I have been talking about this at great length recently, also Pu water blown foams, and he ofcourse is going to build a PET/Basalt OK(dinghy), for himself to sail, and test the whole idea.   He is very aware of these resins and is doing long hand emperical testing, also getting into Life-cycle analysis, not just the boat, but entire campaigns etc etc.

I looked very hard at eco resins, before I started the 89er, but at present, using 1/2 the amount of fibre and consequentially 1/2 the resin was far more appealing, especially as it should give the 89er a very long life-span.

I have promised to give you my thoughts on the enviormental consequences of boat building.    I will do that, but things like clever mould design and silicon bags have allowed us to get our wastage on the existing 49er/29er in total to under 7%, so by that, both hulls as they come out of the moulds are about 60kgs, so adding it all up, over spray, gunk left in the can, foam off cuts, glass off cuts, the biggy is the gunwale triming and the waste, everything is less than, in most cases 4kgs.

I was part of the think-tank global talk fest a month ago, and some of the waste numbers quoted where horrific, waste and minimising useage, increasing longivity will be the focus of what we do going fwd!

and just as a teaser.   Hopefully we will do the final basalt/glass Friday, flip mid next week.

image.thumb.png.361f86863c61b8d094f6896f1f0b4a6c.png

  • Like 6
Link to post
Share on other sites

@JulianB I love seeing the pics of course, which is why I'm here, but I've been recently focused on the idea of sustainable boat building so your comments on that are an added benefit.  I'm working on starting up a boat building company in a different segment and I want to minimize waste and use as many earth friendlier products in the build as possible.  The plan is to use Bio-Resins not only for the boat production being more sustainable but also for the health of the staff. This was my motivation in asking about your approach.  The initial naval architect that we started working with had a similar sentiment earlier on.  Before we started looking at flax or basalt fibers, he mentioned that building with carbon would allow a lighter laminate, less resins, less layup time so lots of material saving benefits from an environmental and financial impact.  We are focused on the latter too as we want our new boats to be at a very competitive price point but I think it's possible to do both.  

  • Like 1
Link to post
Share on other sites

OK, My thoughts on Environmental considerations.

Really, I have 3-4 key points and in order of importance.

#1           Longevity,  

This can most easily be summed up by put any number /∞ and it becomes a very small number.     ∞ (in this case)= lifespaqn

i)                    Therefor if you can double the life span of a boat, virtually regardless of it’s initial environmental cost then is environmental factor is ½ ved so you need to look at why people replace boats and you need to act early to arrest that if it’s simple

a.       Some people replace boats because they can, or because it’s cheaper to turn a boat over and get new sails etc etc, so therefore you need to make sure that there is an afterlife for your boat/sail/mast. (we are doing that now (2nd hand 29er going to Taiwan or re-builds in Brazil)  and the Opie dose it well)

b.       You need to jump on “fake news” because you’re competing in a space and other’s are always after your space.   If you don't jump on it, then the whole sport sufers as it becomes pervieved as "expensive".

ii)                   Good design also come into this, if you see a problem, and you can design your way out of it, you need to do that.   Often this is un-seen, and everything evolves, to think it dose not is absurd, even the Laser with all it’s rules and regs evolve.  

Politically, the biggy here is to keep your sailors informed, and only evolve at a rate that they can bear, some won’t like it, most will expect it as its inevitable especially in Hi-Perf. products.

iii)                 Don’t only think about the part you may produce, think about the means to produce those parts.    In 2008 we did 3 set of 49er tooling, one of those sets which I owe is in-active (for political reasons) so for most of that time, 2 hull moulds made most of the hulls, 13 years, 120 boats a year is 1500 odd boats (out 2 hull moulds.)    Deck moulds, the non-skid destroys them so we are looking at EVA non-skid, and have “clean-skin” deck moulds.    (we added additional sets of mould to meet surge demand, so they are now all cycled, but the original hull moulds are still in use) The Tasar hull mould is still going 25 years on, 29er moulds also last forever.   The silicon vacuum bags that Chris (Ovington) uses are inspirational!   (100+ clamps per bag)

#2           Recyclability

So wherever you can, you need to think about recycled products!   PET is the most obvious!   If we create a demand for a product (PET) that is going into landfill, then less will go into landfill and we create less of the other material (PVC) that would otherwise go into landfill, so in my mine that’s a double benefit.

The 49er presently uses recycled carbon material in its spreaders, and they (spreaders) tend to get bashed about and replaced, so we have devised a system where-as individual arms can be replaced rather than discard the whole spreader.

Mast is the same, so this is more in the longevity bracket, but we have also designed the mast so, it lasts many years of active service and in the event that it is no longer viable, it can also end up as 49er spreaders, or bits of a bicycle frame or a brakes for a 787/Teslar.

Revisiting PET, and this come into Design and Longevity, don’t assume that existing dogma is the only solution, be creative and look at the properties of the material and then match those properties with other materials that have a likeminded, (not necessarily conventional) benefits.

I have matched Basalt with PET, I have redesigned the process and more importantly the interface (between the extremely dense skin and the less dense core) and I am “giving it a go”.

I hope that many more people, have a go, it would be very sad if I was the only one, but I know that I am not, and we need to embrace the process and not stick our heads in the sand!

#3           Total “life cycle” cost

I interestingly watched the Bio-Resin video, and they used infusion.

I have done a lot of infusion, most of it has been done in China and mostly by women, it’s very very clean and very very repetable.   But in more than 90% of the facilities where I have seen this done, the level of disposables is horrific.

But not in all.   And I think that sensible infusion has a big future. 

But it needs well thought out silicon bags, like the ones Chris (Ovington) uses, it needs to use the folds as transfer mediums with recycled material into folds in the bags, rather than miles and miles of spiral tubing, it need multiple short length entry points and capture pots close to exits, and then, on bigger projects, with all the health benefits and the alike, it’s really worth pursuing.

But for one offs, you could easily reach 100% (by weight) of disposables and if you do that, you have to have a good hard look at yourself.

Alex, my son, is quite environmentally aware, so we have wherever we can, re-used things like perforated plastic and vacuum bags, plus we have modified the processes to reduce our dependence on things like Peel ply.   We can’t avoid it, but we can minimise it.    But we are probably at 20%.

As part of that, we have made decision that will cost us, say 15kgs (1.5%) of totally system weight, and the most obvious there is the outer 3.5mm P115 PET skin, we could build the boat 10-15kgs lighter, but it won’t last as long, we would not be able to use far light skins, and the idiot factor would be reduced to a point where 4 fat old bastards need to do a repair rather than enjoy a bottle of red.

29er and 49er wise, as I may have commented before are down around 7%.   29er foils are closed moulded and wastage is down around 0.05%, and we are already looking at going to Pu Eco water based blow cores and Basalt reinforcement.   49er foils (also closed mould) we have already made Flax reinforced foils and now looking at PET or Eco Pu blown foam again with Basalt reinforcements.

& #4       Material Science

Already spoken about Bio-Resins, they where in my mind (and in theirs as they are only using them in) what I would call auxiliary structures, will no doubt advance and come to the fore in a very short period of time, so Chris, again is very actively looking at them now, WRT the 49er and 29er.

(and highly probably the ILCA also, which uses about as much raw resin as the 29er)

Element6 (Thailand) what to look at infusing the 29ers, which you can already do, it's in the manual, quite a few 49er were made via infusion before discontinued due to the level of disposables and weight (they grow about 2 kgs).

Then you get into the PE products and as I commented previously, I have a bit of PE, on my desk in front of me, which was Roto-moulded, which is impressive, and my guess is in 5 years, we will have to be looking at this.

~~~~~~~~~~~~~~~

Guys and Gals, I could expand on this to ∞, if needed, but it's all about having the will.

The big issue in developed countries, is the add-on costs, mean's that infusion will probably make a huge come back, and that is probably a good thing!

 I think that when PE's advance another inevitable round, then we will again find thermo plastics in our Christmas stockings, and be taken far more seriously.

This is a photo taken in 1995, Jonathan McKee & Chris Lanzinger are sailing, it's a very early 49er, made to mimic PE production.

image.png.107f2da4ae24e7d0158840b7cfe1733b.png

If you look closely, the whole mast/rig is sitting in a alloy space frame, so you could completely un-bolt the rig from the hull and maintain rig tension.

Today that would be a Carbon or Basalt single moulded frame (bit like a bicycle) and is very fesiable, this hull remain a test bed for 2 years before being lotteried off and it then sailed for another 10.

                   jB

  • Like 7
Link to post
Share on other sites
6 hours ago, JulianB said:

OK, My thoughts on Environmental considerations.

 

Really, I have 3-4 key points and in order of importance.

 

#1           Longevity,  

 

This can most easily be summed up by put any number /∞ and it becomes a very small number.     ∞ (in this case)= lifespaqn

 

i)                    Therefor if you can double the life span of a boat, virtually regardless of it’s initial environmental cost then is environmental factor is ½ ved so you need to look at why people replace boats and you need to act early to arrest that if it’s simple

 

a.       Some people replace boats because they can, or because it’s cheaper to turn a boat over and get new sails etc etc, so therefore you need to make sure that there is an afterlife for your boat/sail/mast. (we are doing that now (2nd hand 29er going to Taiwan or re-builds in Brazil)  and the Opie dose it well)

 

b.       You need to jump on “fake news” because you’re competing in a space and other’s are always after your space.   If you don't jump on it, then the whole sport sufers as it becomes pervieved as "expensive".

 

ii)                   Good design also come into this, if you see a problem, and you can design your way out of it, you need to do that.   Often this is un-seen, and everything evolves, to think it dose not is absurd, even the Laser with all it’s rules and regs evolve.  

 

Politically, the biggy here is to keep your sailors informed, and only evolve at a rate that they can bear, some won’t like it, most will expect it as its inevitable especially in Hi-Perf. products.

 

iii)                 Don’t only think about the part you may produce, think about the means to produce those parts.    In 2008 we did 3 set of 49er tooling, one of those sets which I owe is in-active (for political reasons) so for most of that time, 2 hull moulds made most of the hulls, 13 years, 120 boats a year is 1500 odd boats (out 2 hull moulds.)    Deck moulds, the non-skid destroys them so we are looking at EVA non-skid, and have “clean-skin” deck moulds.    (we added additional sets of mould to meet surge demand, so they are now all cycled, but the original hull moulds are still in use) The Tasar hull mould is still going 25 years on, 29er moulds also last forever.   The silicon vacuum bags that Chris (Ovington) uses are inspirational!   (100+ clamps per bag)

 

#2           Recyclability

 

So wherever you can, you need to think about recycled products!   PET is the most obvious!   If we create a demand for a product (PET) that is going into landfill, then less will go into landfill and we create less of the other material (PVC) that would otherwise go into landfill, so in my mine that’s a double benefit.

 

The 49er presently uses recycled carbon material in its spreaders, and they (spreaders) tend to get bashed about and replaced, so we have devised a system where-as individual arms can be replaced rather than discard the whole spreader.

 

Mast is the same, so this is more in the longevity bracket, but we have also designed the mast so, it lasts many years of active service and in the event that it is no longer viable, it can also end up as 49er spreaders, or bits of a bicycle frame or a brakes for a 787/Teslar.

 

Revisiting PET, and this come into Design and Longevity, don’t assume that existing dogma is the only solution, be creative and look at the properties of the material and then match those properties with other materials that have a likeminded, (not necessarily conventional) benefits.

 

I have matched Basalt with PET, I have redesigned the process and more importantly the interface (between the extremely dense skin and the less dense core) and I am “giving it a go”.

 

I hope that many more people, have a go, it would be very sad if I was the only one, but I know that I am not, and we need to embrace the process and not stick our heads in the sand!

 

#3           Total “life cycle” cost

 

I interestingly watched the Bio-Resin video, and they used infusion.

 

I have done a lot of infusion, most of it has been done in China and mostly by women, it’s very very clean and very very repetable.   But in more than 90% of the facilities where I have seen this done, the level of disposables is horrific.

 

But not in all.   And I think that sensible infusion has a big future. 

 

But it needs well thought out silicon bags, like the ones Chris (Ovington) uses, it needs to use the folds as transfer mediums with recycled material into folds in the bags, rather than miles and miles of spiral tubing, it need multiple short length entry points and capture pots close to exits, and then, on bigger projects, with all the health benefits and the alike, it’s really worth pursuing.

 

But for one offs, you could easily reach 100% (by weight) of disposables and if you do that, you have to have a good hard look at yourself.

 

Alex, my son, is quite environmentally aware, so we have wherever we can, re-used things like perforated plastic and vacuum bags, plus we have modified the processes to reduce our dependence on things like Peel ply.   We can’t avoid it, but we can minimise it.    But we are probably at 20%.

 

As part of that, we have made decision that will cost us, say 15kgs (1.5%) of totally system weight, and the most obvious there is the outer 3.5mm P115 PET skin, we could build the boat 10-15kgs lighter, but it won’t last as long, we would not be able to use far light skins, and the idiot factor would be reduced to a point where 4 fat old bastards need to do a repair rather than enjoy a bottle of red.

 

29er and 49er wise, as I may have commented before are down around 7%.   29er foils are closed moulded and wastage is down around 0.05%, and we are already looking at going to Pu Eco water based blow cores and Basalt reinforcement.   49er foils (also closed mould) we have already made Flax reinforced foils and now looking at PET or Eco Pu blown foam again with Basalt reinforcements.

 

& #4       Material Science

 

Already spoken about Bio-Resins, they where in my mind (and in theirs as they are only using them in) what I would call auxiliary structures, will no doubt advance and come to the fore in a very short period of time, so Chris, again is very actively looking at them now, WRT the 49er and 29er.

 

(and highly probably the ILCA also, which uses about as much raw resin as the 29er)

 

Element6 (Thailand) what to look at infusing the 29ers, which you can already do, it's in the manual, quite a few 49er were made via infusion before discontinued due to the level of disposables and weight (they grow about 2 kgs).

 

Then you get into the PE products and as I commented previously, I have a bit of PE, on my desk in front of me, which was Roto-moulded, which is impressive, and my guess is in 5 years, we will have to be looking at this.

~~~~~~~~~~~~~~~

Guys and Gals, I could expand on this to ∞, if needed, but it's all about having the will.

The big issue in developed countries, is the add-on costs, mean's that infusion will probably make a huge come back, and that is probably a good thing!

 I think that when PE's advance another inevitable round, then we will again find thermo plastics in our Christmas stockings, and be taken far more seriously.

This is a photo taken in 1995, Jonathan McKee & Chris Lanzinger are sailing, it's a very early 49er, made to mimic PE production.

image.png.107f2da4ae24e7d0158840b7cfe1733b.png

If you look closely, the whole mast/rig is sitting in a alloy space frame, so you could completely un-bolt the rig from the hull and maintain rig tension.

Today that would be a Carbon or Basalt single moulded frame (bit like a bicycle) and is very fesiable, this hull remain a test bed for 2 years before being lotteried off and it then sailed for another 10.

                   jB

Seriously JB a massive thanks for putting all this down, no mean undertaking to just punch all that out on the keyboard, but more importantly to raise awareness from both producers and consumers perspective of what could be done to actually make our sport somewhat more sustainable than the absurd levels of eco-friendly credit it has for too long claimed or hoped to be associated with.

I realise that whilst inertia is also largely at play, by continuing to produce sailboats in unsustainable ways and with large amounts of waste by-product, it is also that frankly dollars talk, and waste management is not framed in cradle to grave terms. Surfing with the production of pure plastic waste and wetsuits is the other standout phony here, of an industry trading on less than green credentials, but I am sure there are many more.

So in the interest of facilitating that sailing concentrates on sorting it's own house first, I appeal to @Editor to consider posting this knowledge of yours on the front page so that awareness within both the industry and the wider audience of customers, users and whatever can help accelerate such technology to become the norm and not an outlier.

Only with cool projects like yours will other get the blinkers off as to how high performance can be environmentally responsible, or at least much better than the current norm.

Link to post
Share on other sites

Thanks for the comments, I consider it simply logical.

The 9er group has recent developed "guiding principals" for how it intends to go fwd WRT enviormental, let me review it, and if I can I will share that.

Finally couple of requests re the early 49er and the space frame, I think the following shot was taken the next day, skipper is Ander Lewander and crew is Peter Mickos, both Swedish, more than anyone Anders developed the cuff luff, though here with a wishbone, it developed at a freighting pace.

I think this Wishbone phote was taken 3rd of 4th Jan 1995image.thumb.png.70f5815b2a613d4be2746f5e4a740168.png

This one was taken Jan 7th 1995, both McKee brothers.

image.thumb.jpeg.1beb681f0fa0f359637cfe5bfd28c29d.jpeg

And this one has Dad sailing in Balmoral June 95 in a whole new hull/wings with the cuff.

image.thumb.jpeg.48a30d4bb4c987683252788389709d86.jpeg

Evoloution is inevitable!    Very stupid to try and fight it!

 

  • Like 5
Link to post
Share on other sites
On 12/5/2021 at 6:11 PM, Boink said:

Seriously JB a massive thanks for putting all this down, no mean undertaking to just punch all that out on the keyboard, but more importantly to raise awareness from both producers and consumers perspective of what could be done to actually make our sport somewhat more sustainable than the absurd levels of eco-friendly credit it has for too long claimed or hoped to be associated with.

I realise that whilst inertia is also largely at play, by continuing to produce sailboats in unsustainable ways and with large amounts of waste by-product, it is also that frankly dollars talk, and waste management is not framed in cradle to grave terms. Surfing with the production of pure plastic waste and wetsuits is the other standout phony here, of an industry trading on less than green credentials, but I am sure there are many more.

So in the interest of facilitating that sailing concentrates on sorting it's own house first, I appeal to @Editor to consider posting this knowledge of yours on the front page so that awareness within both the industry and the wider audience of customers, users and whatever can help accelerate such technology to become the norm and not an outlier.

Only with cool projects like yours will other get the blinkers off as to how high performance can be environmentally responsible, or at least much better than the current norm.

Hi Boink, all is not lost, Julia who drives the 9er Alliance is very green focused.

But above you spoke of wesuits and pure plastic, this morning at the coffeeshop, Michelle, who is a medical scientist heavily involved in Covid research is also heavily into free-diving and scuba and was telling us that all her new wetsuits are PET, then Alex pipped up and all his board shorts and surfing apparel at PET.    Mark Paul (maried to Sarah Kenny who is a VP of WS) has in the past helped me with recycled materials to use in breather cloths along with finding after-life's for FRP and Mylar products, with a fair amount of success.  

If all of this is just happening at our coffeeshop each morning, imagine with a bit of will what can happen everywhere!

I am hopeful.

  • Like 4
Link to post
Share on other sites
1 hour ago, JulianB said:

Hi Boink, all is not lost, Julia who drives the 9er Alliance is very green focused.

But above you spoke of wesuits and pure plastic, this morning at the coffeeshop, Michelle, who is a medical scientist heavily involved in Covid research is also heavily into free-diving and scuba and was telling us that all her new wetsuits are PET, then Alex pipped up and all his board shorts and surfing apparel at PET.    Mark Paul (maried to Sarah Kenny who is a VP of WS) has in the past helped me with recycled materials to use in breather cloths along with finding after-life's for FRP and Mylar products, with a fair amount of success.  

If all of this is just happening at our coffeeshop each morning, imagine with a bit of will what can happen everywhere!

I am hopeful.

As Paul Kelly says - From Little things...... Big things Grow......

Well, again I have come here and learnt stuff - good stuff, positive stuff.......

Was only watching ABC's Australian Story last night about Prof. Veena Sahajwalla's Green Steel Initiative from UNSW and her move into Recycled ceramics for high end building products for Mirvac.......

There certainly is hope but it needs awareness (like the mythical front page.....) To achieve scale and inertia for this to be automatic and commercially ubiquitous.

Elsewhere though, I was depressed to read at the forecasted amount of plastic trapped in the 5 gyres of the oceans....... 89 million tonnes if I recall correctly by 2030.

So I cannot decide if the glass is half full, half empty or cracked and leaking fast.

I get that Life is not binary - Yes/No - Good/Bad or other simplified media concoctions. It's complex and messy.

We are experiencing death by a thousand cuts. We may learn to work around climate change, but will the environment be so irreparably toxic and degraded as to naturally curb life?

These are not concerns for the uber wealthy, but some of them sail, so it's an opportunity to wedge their conscience in a more direct and meaningful manner.

Hence the desire for you to spread the word about performance composites that are a whole lot more sustainable, but not lacking in stiffness, longevity or lightness. I can forsee Basalt/PET/Bio resin dashboards in high end sports cars. Or is that injection moulded? More Ferrari & McLaren than Topper sailboat. Then,who knows where.......?

Maybe your Julia could adapt 9er class rules? 

To only allow competitors to replace their legacy sailing kit with this new style of  technical clothing ( e.g. those PET wetsuits)....... Call it a Benevolent Dictatorship! 

  • Like 2
Link to post
Share on other sites
13 minutes ago, Sailabout said:

I was wondering if you have put some PET in a bucket and let it sit to see how waterproof it is?

The rule of thumb, once you go past P65/H65 which is the point at which 99% of these foams cross-link trhe wtare absorbion rates are a) minimal and b) similar.

Need to point out that Polystrene cross links at a far lower kgs/m³ (H or P), but whether they are PET, PVC or hybrids link CoreCell, once you exceed P-H 65 it's ceases to be a issue, and as you go upwards toward P115, even less so.

But the answer to your queastion is no I have not, and I doubt I will bother, because I am very sure of the answer!

                    jB

  • Like 1
Link to post
Share on other sites
On 12/7/2021 at 7:21 PM, Boink said:

As Paul Kelly says - From Little things...... Big things Grow......

Well, again I have come here and learnt stuff - good stuff, positive stuff.......

Was only watching ABC's Australian Story last night about Prof. Veena Sahajwalla's Green Steel Initiative from UNSW and her move into Recycled ceramics for high end building products for Mirvac.......

There certainly is hope but it needs awareness (like the mythical front page.....) To achieve scale and inertia for this to be automatic and commercially ubiquitous.

Elsewhere though, I was depressed to read at the forecasted amount of plastic trapped in the 5 gyres of the oceans....... 89 million tonnes if I recall correctly by 2030.

So I cannot decide if the glass is half full, half empty or cracked and leaking fast.

I get that Life is not binary - Yes/No - Good/Bad or other simplified media concoctions. It's complex and messy.

We are experiencing death by a thousand cuts. We may learn to work around climate change, but will the environment be so irreparably toxic and degraded as to naturally curb life?

These are not concerns for the uber wealthy, but some of them sail, so it's an opportunity to wedge their conscience in a more direct and meaningful manner.

Hence the desire for you to spread the word about performance composites that are a whole lot more sustainable, but not lacking in stiffness, longevity or lightness. I can forsee Basalt/PET/Bio resin dashboards in high end sports cars. Or is that injection moulded? More Ferrari & McLaren than Topper sailboat. Then,who knows where.......?

Maybe your Julia could adapt 9er class rules? 

To only allow competitors to replace their legacy sailing kit with this new style of  technical clothing ( e.g. those PET wetsuits)....... Call it a Benevolent Dictatorship! 

I think Van Gogh said it before Paul Kelly, but it was something like "great things come form a lot of little things put together".

Regardless, if we all try and if we refrain from “it’s too hard” then we will get somewhere, hopefully fast enough.

Give me a week and I will post the 9er “guiding principles” doc, it’s quite refreshing and we are right now, setting up a zoom conf with WS to fast track through some longevity possibilities in keeping with the “guiding principles” doc.

Few have asked about 49er and 29er foils and moulds.

image.png.90b315c207b05962387edcd8b437715b.png

This is possibly the best engineered set of 29er foils moulds in the world.   Un-fortunately due to political reasons, they have been locked in a container in Qingdao China for over 2 years, but there is a good chance they will start to be used shortly

They 40mm thick alloy, weigh a far bit, milled to the std file, yad yad yad.

The issue WRT blowing cores (and generating “biscuits”) or milling cores (and generating “blanks”) is that even with the best practices, when you mill anything be it PVC, PET or Polystyrene, more than ½ ends up on the floor.

Then there is a hot blow process, where you layup in epoxy, sure some tricks to get material around the LE, but then put a shot of Epoxy blow foam in and close the mould allowing the foam to expand, and you have a dedicated “blow hole” right size so you get to the right pressure inside the mould.    Dose a great job, think the resin system is Sicomen (French).

The other option is to pre-blown biscuits, then you can use Pu Eco foams, and the trick is to use oven bake paper, loves the heat and nothing sticks to it, and it’s re-useable.

Big advantage of this is you can per dictate the density of the core, you can be very confident about the integrity of the core, and can add spars if you wish, and the actual manufacturing process can involve vacuum, which completely eliminates voids.

But the big up-side of blown cores, in closed moulds is virtually no waste, you end up cleaning up grams of gelcoat and that’s about it, plus the products are super repeatable and simple to make.

WRT the 89er we will be using HD epoxy milling board milled moulds (female), for all the foils.    Very likely we will be making  multiple foils, out of the one set of moulds,

We will, after waxing, lay in a laminate (dry), then cover that with “oven bake” and blow Pu cores.

Let them stand for a week, probably use 160kgs/m³ material, ends up about 180kgs/m³.

Then light sand, and straight into the laminate, and vacuum.

The DSS, we may cut the core and generate a W spar, but still, it all happens in one hit.

(DSS is far more highly loaded than the fin, so need to be diligent)

~~~~~~~~~~~~~~~~~

Re the actual boat, it was a manic 10 days, I had to get some mast to Italy, airfreight, but they got off-loaded so they are still at the airport, then I had to drive to Tweed Heads (8hrs each way) and back with my new alloy trailer, so we really only got back into it today.   The current plan is to spend tomorrow detailing the 3.5mm, including a final re-fair and slurry.

Monday, Dad’s army has been called up and we will basalt/s-glass the skin and do the full catastrophe, so peel-ply, perforated plastic, transfer medium and bag/vacuum.

By the end of the week, flip it, and into the inside.

As a side note, when we de-bagged, the hull yesterday, we saved everything, the vacuum bag, all the perforated plastic and transfer medium.     We will use a new bag for the final pull, but everything else get s 2nd or in some cases, 3rd, 4th or 5th use.

The old bag will get re-used pulling down panels or the winglets, whichever comes first!    As will the perforated plastic.  I doubt we will get a 3rd use from the transfer medium, but it’s paper and it’s had a very productive life!

 

  • Like 7
Link to post
Share on other sites
16 minutes ago, JulianB said:

20211213_135003.thumb.jpg.baaa50d514c1493a0738916de3d45615.jpg

Outer layers on, in the Aust sun cooking under a 80% vacuum. A good day at the office.

Love seeing the pics! Between you and Jim Donovan it's a bit like a drug. 

I've been doing some small carbon projects on the side but I'm jonesing for some bigger boat projects so I'm living vicariously through you both.

  • Like 1
Link to post
Share on other sites