89er

[Steve Clark]

I couldn't find a decent photo (the one below was the best) but when watching the 18'ers on YouTube you often see quite a large rostertail between the trailing edge of the hull and leading edge of the rudder. I assumed that little endplate tucked and faired into the hull was to quieten that down...
View attachment 556436

Edit: and then this photo shows up in my Facebook feed to show what I mean!
View attachment 556440

Remember that the rudder has it’s own wave making and creates it’s own wake. If you include the volume of the centerboard and rudder in the curve of areas, you realize that you have extra bumps and the water thinks the hull isn’t fair. In the limit, the boat thinks it is pulling a dinghy. This is another merit of small skinny rudders, and or moving them forward under the boat where they can “hide” in a place with more volume.
The down side is that the shorter the distance between the CP of the board and the CP of the rudder steering gets twitcher. This can be unpleasant at high speed. Hanging the rudder out the back gives you a longer tiller which also helps.
SHC
ICs all had inboard rudders, but they have moved to transom hung because we pull our seats really far aft, and that really limits how long the tillers can be.
The diameter of the shaft ends up being the limiting factor on how thin you can make the foil, which in turn kind of limits the chord length.
I went through a period of making really deep really skinny rudder blades and have concluded that they were really to big. I had been convinced that rudder area and thus absolute “never stall” control was pretty cheap. I have revised my thinking and rudder blades are getting smaller again.

 

[WCB]

I got it up, how's yours Jim???

View attachment 556628

It looks far bigger now...nice work!

 

[JulianB]

So a huge day, 07:30 start, (GT HAD to sail (beer can) race this afternoon), and we got the mast up, back down, heel tuned, back up again and back in it's slot (with the mast still up) to be back in time to make dock-call for GT.
I bailed on beer-can racing, and got into Fin boot, and all those other small fiddly bits than stop you going sailing.

Mast just prior to launch, with GT working out balance point, with the crane it was a breeze, super simple. Whole mast inc everything weighs 22kgs.

Setting the boot, the yellow is just what I had, way to soft, need to re-do it in a decent Polyurethane. Don't skimp! But Deidre (my wife) likes the colour!

First shot at the boot, will do a "2nd shot" tomorrow morning. I'm using a 85 dromina Pu material (similar to a soft skateboard wheel).

Fin (& Rudder) have wet-n-dried up really well.

Tomorrow, we will set the rake, then set the rig tensions, then get the sails up.
Hopefully around 17:00 we may go for a sail.
My sister Nicky, Alex (my son) GT, Jack and Keith (Nicky's husband) will be the crew.

Let you know how we go tomorrow.

May be early bubbles, and then the work really begins!

jB

 

[JulianB]

It looks far bigger now...nice work!

10.7 - 10.8m off the deck, depends on how you measure it. By our Sportsboats stds, its short.

The new Lamborgini (the 2nd 89er) is planning on max height which is about 12.5m off the deck.

 

[WCB]

10.7 - 10.8m off the deck, depends on how you measure it. By our Sportsboats stds, its short.

The new Lamborgini (the 2nd 89er) is planning on max height which is about 12.5m off the deck.

I should have been more clear...I meant the hull. Most perspectives have been from one end or the other and now seeing it from the side it looks much bigger.

 

[allweather]

now seeing it from the side it looks much bigger.

Completely different! Don‘t want to say massive on account of the low weight, but seeing the sides like that in black looks far bigger than before.

Can‘t wait for the on the water pictures and still amazed how quick it feels.

 

[Varan]

I should have been more clear...I meant the hull. Most perspectives have been from one end or the other and now seeing it from the side it looks much bigger.

They shrink when they hit the water.

 

[Mizzmo]

I got it up, how's yours Jim???

View attachment 556628

I don't know how I missed it earlier, but that bow is really sexy. JB can you talk about how you came to that shape? Also congrats not the rig, it looks fast.

 

[chris foiler]

Well done way ahead of me

 

[JulianB]

Hi all, the plan was to hit the water yesterday.

Unfortunately plans of mice and men (particularly apt give the Douglas Adams bent) went astray at the last moment as the jibs appear to be a tad oversize and would not sheet.
Got everything else done, 2nd fill of Pu in the boot went well, got the bulb in the back of the Territory, got the foils all nicely sanded down, all the extra splices, main up, later the spin up, sure needed tweaks like batten tensions, etc etc, my sister Nicky arrive (from 2 hrs north) only to find jibs a tad over size.

My stupidity, in not checking earlier, anyway, reaction of Andrew (Doyle sails) was impressive, a) firstly he could not believe it but photos don’t lie, & b) within 3hr he had the sails bricked and they are now on their way to Tasmania (2 hr flight sth) and should be back in Sydney Wednesday for a 2nd attempt at going sailing.

So went Greek (for dinner) with some great bottles of red and feeling no pain.

Watch this space.

I don't know how I missed it earlier, but that bow is really sexy. JB can you talk about how you came to that shape? Also congrats not the rig, it looks fast.

Mizzmo, for years we have been quite anal about the fwd sections of the hull.

This boat, 89er is completely different to say a 29er and even more so compare to a 49er.
The 89er is highly unlikely to exceed say 9knts upwind, where as a 49er goes upwind 99% at speeds above 9knts, plus a 49er is 300-310 kgs all up whereas the 89er is 1 tonne all up.
(29er, kids will be kids and they are fearless, so they push it so much harder)

So in designing the 89er, it's all about not losing too much energy as the boat goes up-wind and punches into waves. Plus, there is inertia, so it's not going up and down (pitch) that much, and if it starts to hobby-horse there are different ways to stop that.

So were as a 49er (& 29er), you have to have a series of wedges, Freud angles, and its better that they do not get wider (obtuse), But they need to get Bigger as you progress up the topsides because the 49er dose not confirm to the water (wave) surface and it’s moving fast, the only way to do that well is throw the bow fwd at the top, so you get the classic raked “9er” bow, (plus it makes it really easy to make). The Freud angles of the bows of 49er and 29er are near as dam it isoclinal (constant) as you go up the sides, I did do a diagram about this in the past, so I dug that out and did it with the 89er also.

These are the fwd WL's of a 49er, very regular. 29er is near identical, and the 29er hull shape is possibly the best thing I have done (Mk3"c" B18, (Nokia) was very similar), it can carry weight, (XX and XS rigs), it can handle power (XX rig/Nokia) it dose not get overwhelmed, it's forgiving, it's the present end of 40 years of refinments hold a very defined set of parameters, Vicvce and Don't Panic (Plus the SKUD) are benificaries of all that. 29er shape is not the right shape for a 49er. 49er is a far more powerfull, different wants.

And with the 89er, you have another and completely different set of wants. You easily overcome the “plunge” factor by increasing the height of the topside a little, but to stop the slamming into waves, again you hold the Freud angles constant but simply allow the boat to “run” out in terms of lines in the front 20%.

These are the fwd WL's of the 89er, similar but fundementally different!
And yes, very Bethwaite straight! No hollows, no convex, and no U's!
The coloured lines are at the same relative heights, coming up the topsides.

At around 20% back from the bow, the 29er (to a leaser extent the 49er) and 89er are very similar shapes in terms of weight carrying capacity, and technically the way they try to move the water with the least resistance. Going further aft, the 89er and the 29er are only different because of surface areas which defines chine width and rocker depth to accommodate different weights.

But a) because it was MY boat, b) because I don’t have to manufacture it and c) because it’s technically pure and the most efficient way to handle the bow sections, I did it!

 

[Jim Donovan]

Nice JB!

Mine's still sitting in the shed. Batch of crappy weather past couple days; cold (3C), pouring rain, and wind gusts to 35 knots. Add a dead truck battery into that mess.

I see you cheated and used a crane; how easy is that!

Spent yesterday afternoon building a gin pole, extending the 34 footers old aluminum 11 ft spinnaker pole to 18 ft, had to shape the top 18" of a 9 ft long 3 x 3 piece of wood to fit inside the tube. Weather broke yesterday afternoon, so the plan is step today (our Friday).

 

[Scillyjosh]

Hi all, the plan was to hit the water yesterday.

Unfortunately plans of mice and men (particularly apt give the Douglas Adams bent) went astray at the last moment as the jibs appear to be a tad oversize and would not sheet.
Got everything else done, 2nd fill of Pu in the boot went well, got the bulb in the back of the Territory, got the foils all nicely sanded down, all the extra splices, main up, later the spin up, sure needed tweaks like batten tensions, etc etc, my sister Nicky arrive (from 2 hrs north) only to find jibs a tad over size.
View attachment 556905

My stupidity, in not checking earlier, anyway, reaction of Andrew (Doyle sails) was impressive, a) firstly he could not believe it but photos don’t lie, & b) within 3hr he had the sails bricked and they are now on their way to Tasmania (2 hr flight sth) and should be back in Sydney Wednesday for a 2nd attempt at going sailing.

So went Greek (for dinner) with some great bottles of red and feeling no pain.

Watch this space.



Mizzmo, for years we have been quite anal about the fwd sections of the hull.

This boat, 89er is completely different to say a 29er and even more so compare to a 49er.
The 89er is highly unlikely to exceed say 9knts upwind, where as a 49er goes upwind 99% at speeds above 9knts, plus a 49er is 300-310 kgs all up whereas the 89er is 1 tonne all up.
(29er, kids will be kids and they are fearless, so they push it so much harder)

So in designing the 89er, it's all about not losing too much energy as the boat goes up-wind and punches into waves. Plus, there is inertia, so it's not going up and down (pitch) that much, and if it starts to hobby-horse there are different ways to stop that.

So were as a 49er (& 29er), you have to have a series of wedges, Freud angles, and its better that they do not get wider (obtuse), But they need to get Bigger as you progress up the topsides because the 49er dose not confirm to the water (wave) surface and it’s moving fast, the only way to do that well is throw the bow fwd at the top, so you get the classic raked “9er” bow, (plus it makes it really easy to make). The Freud angles of the bows of 49er and 29er are near as dam it isoclinal (constant) as you go up the sides, I did do a diagram about this in the past, so I dug that out and did it with the 89er also.

View attachment 556990
These are the fwd WL's of a 49er, very regular. 29er is near identical, and the 29er hull shape is possibly the best thing I have done (Mk3"c" B18, (Nokia) was very similar), it can carry weight, (XX and XS rigs), it can handle power (XX rig/Nokia) it dose not get overwhelmed, it's forgiving, it's the present end of 40 years of refinments hold a very defined set of parameters, Vicvce and Don't Panic (Plus the SKUD) are benificaries of all that. 29er shape is not the right shape for a 49er. 49er is a far more powerfull, different wants.

And with the 89er, you have another and completely different set of wants. You easily overcome the “plunge” factor by increasing the height of the topside a little, but to stop the slamming into waves, again you hold the Freud angles constant but simply allow the boat to “run” out in terms of lines in the front 20%.

View attachment 556994

These are the fwd WL's of the 89er, similar but fundementally different!
And yes, very Bethwaite straight! No hollows, no convex, and no U's!
The coloured lines are at the same relative heights, coming up the topsides.

At around 20% back from the bow, the 29er (to a leaser extent the 49er) and 89er are very similar shapes in terms of weight carrying capacity, and technically the way they try to move the water with the least resistance. Going further aft, the 89er and the 29er are only different because of surface areas which defines chine width and rocker depth to accommodate different weights.

But a) because it was MY boat, b) because I don’t have to manufacture it and c) because it’s technically pure and the most efficient way to handle the bow sections, I did it!

Sails and rig are looking great! Is that the Doyle alternative to 3Di? I'm intrigued as to why in non 9er style you've not got the cuff luff setup?

 

[Rantifarian]

Nice JB!

Mine's still sitting in the shed. Batch of crappy weather past couple days; cold (3C), pouring rain, and wind gusts to 35 knots. Add a dead truck battery into that mess.

I see you cheated and used a crane; how easy is that!

Spent yesterday afternoon building a gin pole, extending the 34 footers old aluminum 11 ft spinnaker pole to 18 ft, had to shape the top 18" of a 9 ft long 3 x 3 piece of wood to fit inside the tube. Weather broke yesterday afternoon, so the plan is step today (our Friday).

Rather than a gin pole, we extended the winch post up as an attachment for the Kite halyard when winching up the mast, as well as an extendable mast yoke at the transom. It's only ever the bottom third of the lift that has the shitty angles, and the old tin noodle rig for the e780 buckles out of column if you compress it by winching too hard

 

[JulianB]

Sails and rig are looking great! Is that the Doyle alternative to 3Di? I'm intrigued as to why in non 9er style you've not got the cuff luff setup?

Re Sails, this a new boat so I was not all that interested in 3Di or Stratis technology initially, so these are a Carbon-based Mylar cloth in a tri-radial configuration. Point being getting the boat on the water is stage #1, refining the boat and getting it going will be stage #2 and then in a year or 2, we may go for 3Di or Stratis or One Sail all in one, or I really have wanted to do my own sails for years, in pure Mylar on home-built moulds, so maybe I can do that.

But at this stage, Andrew Lectie has done a brilliant job, re the design of the sails, the main looked really good, once we tweaked it a bit, the jibs though a tad too big looked great, so, sure tad annoyed but very happy with Andy/Doyle so far. I'm sure Ben at North could have done a great job, but the cards did not fall that way through no fault of Ben's.

Re the cuff luff, it comes down to reefing, 90%. And then the other 10% comes down to fitting the cuff. I have watched Maka, and now Nirto (North) do it and it ain’t that simple to fit the cuff.

But 90% of the decision was, we will reef this main, and we will shake that reef out, and to use my sisters rule, we want to be able to do that in 8 secs, either way.
We did a test bench so to speak, and with a Cuff Luff you will never hit anything like a 8 sec reef, because you need load bearing zippers and all sort of other comlications.

So std tack arrangement and std vang, but we will add a C2 Byte or 18teen type post luff-cuff and we will practice an 8 sec reef, which we believe we can do with 2 crew, going up-wind, on the fly so to speak. The shake out of the reef we believe we can do in a std tack and will require 4 of the 6 crew to manage.

Time will tell.

 

[JulianB]

Rather than a gin pole, we extended the winch post up as an attachment for the Kite halyard when winching up the mast, as well as an extendable mast yoke at the transom. It's only ever the bottom third of the lift that has the shitty angles, and the old tin noodle rig for the e780 buckles out of column if you compress it by winching too hard

The mast ain’t that heavy, I think 22-24kgs all up, shrouds, halyards, spreaders, etc.

6Pac’s mast was 34kgs, and we regular “hand hoisted” that without cranes.

The luxury of the crane was that we could get the mast up and fine-tune shroud lengths “live” so to speak, but now that they are right, we have game-planned a hand launch, we need two in the boat and one of the ground to do that, no jigs or A-frames, we just walk it up, if 6 Pac's was anything to go by)

BTW, put 400kgs on the F/Stay (M6 SK99) and 500kgs (M5 SK99) on the Shrouds and left the tension on, now for 48 hours, and there is no sign of creep, it’s holding tension. Those are base settings, I would expect to go up around 580-600kgs on the shrouds in 20+ knts.

 

[JulianB]

Saturday Night, sitting down with the wife watching some idiot box, got a call from Andy, in Hobart, talking about jibs and re-cuts, that went on for about an hour. Think we were the victims of a scaling error, between the 3D programs, His read one number mine measured another.

The importance of actually taking base numbers to ensure that you get it right!!

He was in the loft yesterday (Sunday), not sure those of you in the Norther Hemp get the significance of this.

This time of year if your not going to Hobart one Boxing Day your no-body!

All the lofts are massively booked up and out, even basic repairs, the standard line is come back mid-January, so super appreciative of Andy and his efforts. Hopefully we will see the fruits of his labours later this week and we get to go get wet.

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

Spent the enforced delay, tweaking rigging and getting some other things right, so not at all idle.

One of the things that I did, was I come from the skiff/9er world, and all things 9er, people get very hung up about rig tensions.

There are load cells and Loogs gauges, but 99% of people just read the number on-top.

I can tell you that a 29er F/stay is 19-24 and that a 49er one is about 24-32, but given I had target loads and given that I was using SK99, would a Loogs design to measure wire, measure rope.

So I set up a test bed and went and measured M3, M4, M5 & M6 SK99.

My super simple test bench,
Red Hook is attached to 1 tonne chain-block that applies the tension.
Orange is my load cell.
Loogs Gauges, PT2 on the table, PT1 in use, you have to switch if you want reliability.
Sample strops & the ubiquitous Expresso Macchiato.

So what I found;

• A Loogs gauge dose reliable measure rope (not reason it should not)
• By this I mean not only does it read rope
• But going up and down a few time it gives similar numbers (within 0.2%)
• The Loogs number = kgs/lbs is close but, dare I say, not accurate.
• That you do have to switch between gauges if you want accuracy (PT1 vs PT2) &
• It was very easy to do the calibration.

To save you doing the work, this is what I found

This is in Kgs.

The M4 on the PT2 was inacurate, where on the PT1, is was a lot better.

The graphs for those that are interested

Blue is M6
Red M5
Yellow M4 &
Cyan is M3

 

[allweather]

To save you doing the work, this is what I found

Don't mind me saving the data. This is wonderful for anyone with a loose gauge and some SK99 but no load cell!(still looking at a tackle instead of ram right now...)
Always wondered about how to measure after switching to a dyneema backstay and this neatly resolves having to do the work.(or rely on reference numbers of forestay tension and mast bend on the specific boat)

It's pretty cool that it is surprisingly close to the wire numbers, which makes sense with wires that can be coiled too, but certainty about the exact difference is so much better.

Think we were the victims of a scaling error, between the 3D programs, His read one number mine measured another.

raises fist angrily into the air: Software!

That is a big shame and astonishing how it can happen when everything "should" be slotting together... Good reminder I suppose to always take that second look at the communicated key sizes just to see if something absurd has occurred.

Conversely as cool as you said that he went and adjusted the sail in spite of the current time frame. On a Sunday no less!
Until later this week~

 

[JulianB]

Don't mind me saving the data. This is wonderful for anyone with a loose gauge and some SK99 but no load cell!(still looking at a tackle instead of ram right now...)
Always wondered about how to measure after switching to a dyneema backstay and this neatly resolves having to do the work.(or rely on reference numbers of forestay tension and mast bend on the specific boat)

It's pretty cool that it is surprisingly close to the wire numbers, which makes sense with wires that can be coiled too, but certainty about the exact difference is so much better.


raises fist angrily into the air: Software!

That is a big shame and astonishing how it can happen when everything "should" be slotting together... Good reminder I suppose to always take that second look at the communicated key sizes just to see if something absurd has occurred.

Conversely as cool as you said that he went and adjusted the sail in spite of the current time frame. On a Sunday no less!
Until later this week~

Happy it's of some use, here it is as a excel doc.

jB

	M6	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35
	160	177	195	214	234	254	275	297	320	345	372	402	434	470	512	562	621	694	784	886
	M5	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
	219	240	262	285	309	336	366	401	445	506	575	653	739	832	911
	M4	16	17	18	19	20	21	22	23	24	25		PT2
	316	357	402	450	501	558	625	705	802	911
	M4	29	30	31	32	33	34	35	36	37	38	39	40	41	42		PT1
	175	187	202	220	240	263	286	309	338	378	430	496	576	675
	M3	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35
	112	120	129	137	147	158	171	187	205	226	249	274	300	329	362	410

 

[JulianB]

Btw, I have also had 1/2 tonne down each shroud and about 300kgs down the F/stay since last Wednesday, no creep todate.

Other big plus, boat has not groaned or cracked or bent.

That was one of the reasons I did the calibration of the Loogs gauge.

jB

 

[stinky]

Saturday Night, sitting down with the wife watching some idiot box, got a call from Andy, in Hobart, talking about jibs and re-cuts, that went on for about an hour. Think we were the victims of a scaling error, between the 3D programs, His read one number mine measured another.

The importance of actually taking base numbers to ensure that you get it right!!

He was in the loft yesterday (Sunday), not sure those of you in the Norther Hemp get the significance of this.

This time of year if your not going to Hobart one Boxing Day your no-body!

All the lofts are massively booked up and out, even basic repairs, the standard line is come back mid-January, so super appreciative of Andy and his efforts. Hopefully we will see the fruits of his labours later this week and we get to go get wet.

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

Spent the enforced delay, tweaking rigging and getting some other things right, so not at all idle.

One of the things that I did, was I come from the skiff/9er world, and all things 9er, people get very hung up about rig tensions.

There are load cells and Loogs gauges, but 99% of people just read the number on-top.

I can tell you that a 29er F/stay is 19-24 and that a 49er one is about 24-32, but given I had target loads and given that I was using SK99, would a Loogs design to measure wire, measure rope.

So I set up a test bed and went and measured M3, M4, M5 & M6 SK99.

View attachment 557518

My super simple test bench,
Red Hook is attached to 1 tonne chain-block that applies the tension.
Orange is my load cell.
Loogs Gauges, PT2 on the table, PT1 in use, you have to switch if you want reliability.
Sample strops & the ubiquitous Expresso Macchiato.

So what I found;

• A Loogs gauge dose reliable measure rope (not reason it should not)
• By this I mean not only does it read rope
• But going up and down a few time it gives similar numbers (within 0.2%)
• The Loogs number = kgs/lbs is close but, dare I say, not accurate.
• That you do have to switch between gauges if you want accuracy (PT1 vs PT2) &
• It was very easy to do the calibration.

To save you doing the work, this is what I found

View attachment 557526
This is in Kgs.

The M4 on the PT2 was inacurate, where on the PT1, is was a lot better.

The graphs for those that are interested

View attachment 557528

Blue is M6
Red M5
Yellow M4 &
Cyan is M3

love that you're doing the graphing in Rhino