soma

Gunboat 68

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20 hours ago, dcnblues said:

I don't think you need anything to smoke. I think you need to eat more fish. Not sure it'll help though...

 

In the link you provide they say that they use a variable pitch servo prop to give optimum efficiency in both forward and reverse. I don't see where there is a need to switch props.

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3 minutes ago, Mizzmo said:

In the link you provide they say that they use a variable pitch servo prop to give optimum efficiency in both forward and reverse. I don't see where there is a need to switch props.

We haven't launched our Gunboat 5508 project yet, but the ServoProp from OV was promising. We reportedly can get up to 10kw of charging from the prop. They've had some software issues that we were hoping would be resolved, but I can't imagine why you'd need more than 10kw of charging. And the best part? No robots needed! 

(Btw-I didn't know robots made the bow thruster go up and down. That was news to me!). 

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On 9/22/2019 at 2:06 AM, dcnblues said:

Gee sparky, scraping barnacles with a painters knife doesn't give you any automatic credibility to speculate about yacht design and construction. In fact, not needing to do so frees up a lot of time to read and search the internet. Maybe you should try it sometime. You don't need to own something that floats to be interested in things that float. Or to speculate about them. I've spent enough time on boats, working on boats in boat yards, delivering boats, racing them, and working on motorcycles to SPECULATE on this thread without having to list credentials. If you think you can make yourself feel bigger by getting some leverage on or discrediting someone who is pro-innovation, why don't you go do it on a different thread. This one is about an innovative company, and their innovative, brand new, beautifully designed boat. Wooden boats has a great forum. Why don't you go there??

That was pretty nasty, who is to say that there is no innovation in Wooden boats? Honestly I figured a guy like you would have done some interesting mods. The rest you inferred based on your personal attitudes.

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This thread has gotten nasty and that's too bad. On the other hand I have learned some interesting things I didn't know before or had forgotten existed.

Also, the original phrasing by dcnblues ("robotic arm") may have seemed... far-fetched, but the same idea described differently has some appeal, like for example a combination of a retractable system and automatic swapping of blades.

... and 10kW out of ServiProp? Wow, awesome.

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1 hour ago, soma said:

We haven't launched our Gunboat 5508 project yet, but the ServoProp from OV was promising. We reportedly can get up to 10kw of charging from the prop. They've had some software issues that we were hoping would be resolved, but I can't imagine why you'd need more than 10kw of charging. And the best part? No robots needed! 

(Btw-I didn't know robots made the bow thruster go up and down. That was news to me!). 

Ok soma just read that and was like what, no way 10kw.  I know we get about 5kw at 14 knots of boat speed, so went to the oceanvolt website and found this.  Not close to 10kw of regen.  But 3kw and more at faster speeds is nothing to sneeze about. On FT we need to turn the regen down on long passages because we don't have the capacity to store it.  

I think the vari pitch prop for this application may be more  marketing than actual real world benefit.  I think you  only need it when you get going crazy fast, otherwise the fixed pitch is fine.  And those crazy speeds don't hapen often and when they do I am more woried about not crashing the boat then making electricity.  There are probably smarter people out there that know more but I am talking from real world experiance.  We are using the three bladed folding gori prop. And we are not using the overdrive feature.

From the oceanvolt website: "A normal fixed propeller (that by nature does not have the blades ideally shaped for regeneration) generates less than half the power of ServoProp at a given boat speed. ServoProp is capable of generating more than 1 kW at 7-8 knots & 3 kW at 11-12 knots. The power generated can be used to power both the propulsion system as well as all the electronics on board without the need to have a separate generator. With this in mind we can definitely start talking about the possibility of a totally self-sufficient cruiser!"

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1 hour ago, soma said:

(Btw-I didn't know robots made the bow thruster go up and down. That was news to me!). 

Does it have software that is programmable? Does it have it's own contained power supply? Does it move up and down according to that program, hydraulically? Does it provide thrust, and retract  invisibly into a larger body? How the F is it not a robot arm (with a dedicated and custom designed propeller)?

*Any complaints about nastiness should be directed to this guy who doesn't seem over his relationship with his former employer. I merely give what I get.

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1 hour ago, Mizzmo said:

In the link you provide they say that they use a variable pitch servo prop to give optimum efficiency in both forward and reverse. I don't see where there is a need to switch props.

Read it again, slowly. It'll hopefully come to you. And anyone who knows the first thing about props understands they are compromised, inverse-relationship nightmares. What's the rpm range of your engine? How important is low drag? Do you want the complexity of having them fold, or pitch sideways when not under power?

And regen is way, way different in optimal design than forward, low rpm torque. This is why Gunboats still rely on diesel and gensets. Imagining a solution isn't delusional. It'll get here sooner or later.

Quote

A normal fixed propeller (that by nature does not have the blades ideally shaped for regeneration) generates less than half the power of ServoProp at a given boat speed. Oceanvolt ideal propeller

 

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1 hour ago, Rocket Raccoon said:

...Also, the original phrasing by dcnblues ("robotic arm") may have seemed... far-fetched, but the same idea described differently has some appeal, like for example a combination of a retractable system and automatic swapping of blades.

Nicely said. All I wrote was offhand speculation about what FUTURE designers would come up with.

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For gosh sake folks. Put the idiot on ignore and the problem goes away. Wrecking good threads. Use the ignore tool and stop quoting and replying to him. I may not want a GB but I sure (used to) appreciate the learning from many of the experienced multihull posters this thread. 

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2 hours ago, soma said:

...more than 10kw of charging. And the best part? No robots needed!

 

You sure about your terms there, sparky? I don't think you are. What I do think is that you should maybe pick someone else to fuck with.

 

Quote

-Intelligent motor control allows recharging the batteries through hydro generation while sailing above 6kn just a push of a button. ..."Intelligent"

-The software controlled variable pitch sail drive adjusts the pitch of the propeller blades automatically "Software Controlled"

-A key part of Oceanvolt is the remote system monitoring and management known as RSI Remote system monitoring and management

Quote

A robot is a machine—especially one programmable by a computer— capable of carrying out a complex series of actions automatically. -Definition of 'robot'. Oxford English Dictionary.

 

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9 minutes ago, Wess said:

For gosh sake folks. Put the idiot on ignore and the problem goes away. Wrecking good threads. Use the ignore tool and stop quoting and replying to him. I may not want a GB but I sure (used to) appreciate the learning from many of the experienced multihull posters this thread. 

You don't seem to be grasping it. When you intelligently refute any single point of the dozens I've recently made, you get to give advice. When all you can do is toss out invalid ad hominem attacks like a dim 3rd grader, you're the one who looks like an idiot who should go away. So do that. Go away. Or shut your pie hole.

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24 minutes ago, dcnblues said:

You don't seem to be grasping it. When you intelligently refute any single point of the dozens I've recently made, you get to give advice. When all you can do is toss out invalid ad hominem attacks like a dim 3rd grader, you're the one who looks like an idiot who should go away. So do that. Go away. Or shut your pie hole.

You must be fun at parties. Thanks for cocking up an awesome thread with inside info on one of the coolest boats ever made. Well done. 

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1 hour ago, dcnblues said:

*Any complaints about nastiness should be directed to this guy who doesn't seem over his relationship with his former employer. I merely give what I get.

No, it's you dude.  Bad attitude.  Dumb questions are fine but belligerent ignorance is unacceptable.  Stop pissing in the pool.

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1 hour ago, dcnblues said:

 You don't seem to be grasping it. When you intelligently refute any single point of the dozens I've recently made, you get to give advice. When all you can do is toss out invalid ad hominem attacks like a dim 3rd grader, you're the one who looks like an idiot who should go away. So do that. Go away. Or shut your pie hole.

Nobody wants you here.  Go away and don't come back.

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No, rather come back, tone down the rhetoric, and chill. It's not worth arguing or getting twisted over...and probably look into the posting history of some of the guys you are getting into it with. Everyone has a bad day, or two. 

O.K. Now back to what started PropSwapGate. 

Technically I would tend to agree that a variable pitch prop might not achieve the same thing as an entirely different prop, unless of course the variable pitch prop can magically grow in size. Watt and Sea sell a few different replacement props of 200mm, 230mm, 280mm depending on average boatspeed. I'm not sure if each prop has the same or different pitch. 

As for jumping all over DCN for maybe using the term robotic? What would you prefer, electro-mechanical?

Dare to dream boys. Dare to Dream. 

 

 

 

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Hey @soma and @Greenflash or others with experience in this.

*  How light can you go on the outer skin before you start to have a significant risk of crushing and puncture damage in real life cruising environments?  If this isn't confidential and you can share, what is GB using (they seem to do OK in real life cruising environment) as an outer hull laminate?

Friend and I both have large-ish tris.  Mine more cruise orientated in design brief his more race orientated.  Both cored boats obviously.  His thermo-formed (? not sure that is the correct term?) mine w kerfs. We both have fairly light inner hull skins.  Both of us have had recent reason to do some hull repairs and we see well built boats.  My damage from massive lightning strike.  His from simple rock and roll while rafted to another boat and well secured and bumpered.  I would never in a million years think a bumper could this but he had some significant crushing (where the bumpers were) through the outer skin which looks to be carbon at a thickness equal to about 200-300 grams per square meter mat (and similar inner).  My outer hull laminate is more beefy.  

So back to the question... at what stage do you start to worry the outer hull is too thin/light for real life boating? 

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14 hours ago, dcnblues said:

Does it have software that is programmable? Does it have it's own contained power supply? Does it move up and down according to that program, hydraulically? Does it provide thrust, and retract  invisibly into a larger body? How the F is it not a robot arm (with a dedicated and custom designed propeller)?

*Any complaints about nastiness should be directed to this guy who doesn't seem over his relationship with his former employer. I merely give what I get.

I’ll keep this polite, but that is not a robot in any way. Robots and industrial automation are what I do for a living. I have 58 robots under my care, with 11 more coming next month. I’m pretty sure I know what meets the definition. 
 

Using your logic, my garage door is a robot. 
 

Now, if you really wanted, I could design your self switching prop contraption in about a half hour. I sure wouldn’t trust it to be reliable though. We use a similar concept all the time at work. We have tons of bores and hones that swap heads on their own as part of their process. In fact, the one I was just working on had 32 heads used by 1 spindle. Granted, it’s the size of a van, but think how much fun you’d have with 32 propellers!  :D

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1 hour ago, Wess said:

Hey @soma and @Greenflash or others with experience in this.

*  How light can you go on the outer skin before you start to have a significant risk of crushing and puncture damage in real life cruising environments?  If this isn't confidential and you can share, what is GB using (they seem to do OK in real life cruising environment) as an outer hull laminate?

Friend and I both have large-ish tris.  Mine more cruise orientated in design brief his more race orientated.  Both cored boats obviously.  His thermo-formed (? not sure that is the correct term?) mine w kerfs. We both have fairly light inner hull skins.  Both of us have had recent reason to do some hull repairs and we see well built boats.  My damage from massive lightning strike.  His from simple rock and roll while rafted to another boat and well secured and bumpered.  I would never in a million years think a bumper could this but he had some significant crushing (where the bumpers were) through the outer skin which looks to be carbon at a thickness equal to about 200-300 grams per square meter mat (and similar inner).  My outer hull laminate is more beefy.  

So back to the question... at what stage do you start to worry the outer hull is too thin/light for real life boating? 

Wess,

A's are generally 200gsm fiber on the outside. They will dent somewhat easily, well, the lighter foam core boats do but hard isn't good for nomex. They are not particularly cut resistant. Puncture wise, they do okay (i.e rocks/hard pilings etc.). Lots depends on where the hit is, i.e highly curved areas are stronger than large flat areas. Personally I think 400gsm on the outside of a reasonable core is about the limit for a real-life cruising boat where weight/racing is less of a concern. Again, many variables and each owner is different. I suspect both the GB and Outremer series are over-built in this area because of the loads involved. On smaller boats (under 40 feet) its a bigger concern because the laminate required for the loads in some areas can be less than that necessarily for avoiding damage at the dock/raft.

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1 hour ago, Wess said:

Hey @soma and @Greenflash or others with experience in this.

*  How light can you go on the outer skin before you start to have a significant risk of crushing and puncture damage in real life cruising environments?  If this isn't confidential and you can share, what is GB using (they seem to do OK in real life cruising environment) as an outer hull laminate?

Friend and I both have large-ish tris.  Mine more cruise orientated in design brief his more race orientated.  Both cored boats obviously.  His thermo-formed (? not sure that is the correct term?) mine w kerfs. We both have fairly light inner hull skins.  Both of us have had recent reason to do some hull repairs and we see well built boats.  My damage from massive lightning strike.  His from simple rock and roll while rafted to another boat and well secured and bumpered.  I would never in a million years think a bumper could this but he had some significant crushing (where the bumpers were) through the outer skin which looks to be carbon at a thickness equal to about 200-300 grams per square meter mat (and similar inner).  My outer hull laminate is more beefy.  

So back to the question... at what stage do you start to worry the outer hull is too thin/light for real life boating? 

Greenflash knows this stuff way better than me, but I think CE requires 1200gm for recreational/cruising boats. A lot of the super light GB competitors achieve their weight savings by not building to CE. It's ok and safe, it's just an advantage that GB/HH choose to not use. I don't necessarily agree with that decision, but gIven insurability issues, building to CE has its appeal. 

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16 hours ago, robalex117 said:

Ok soma just read that and was like what, no way 10kw.  I know we get about 5kw at 14 knots of boat speed, so went to the oceanvolt website and found this.  Not close to 10kw of regen.  But 3kw and more at faster speeds is nothing to sneeze about. On FT we need to turn the regen down on long passages because we don't have the capacity to store it.  

I think the vari pitch prop for this application may be more  marketing than actual real world benefit.  I think you  only need it when you get going crazy fast, otherwise the fixed pitch is fine.  And those crazy speeds don't hapen often and when they do I am more woried about not crashing the boat then making electricity.  There are probably smarter people out there that know more but I am talking from real world experiance.  We are using the three bladed folding gori prop. And we are not using the overdrive feature.

From the oceanvolt website: "A normal fixed propeller (that by nature does not have the blades ideally shaped for regeneration) generates less than half the power of ServoProp at a given boat speed. ServoProp is capable of generating more than 1 kW at 7-8 knots & 3 kW at 11-12 knots. The power generated can be used to power both the propulsion system as well as all the electronics on board without the need to have a separate generator. With this in mind we can definitely start talking about the possibility of a totally self-sufficient cruiser!"

3kw at 11-12 knots, but we were told (huge caveat goes along with that) that we could expect up to 10kw at speed. The appeal of the servoprop is obviously being able to dial in the desired charging rate. Slight pitch for regen at high speed, a lot of pitch did one engine motor sailing, etc. 

Whether we achieve any of that is yet to be seen. 

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14 minutes ago, soma said:

3kw at 11-12 knots, but we were told (huge caveat goes along with that) that we could expect up to 10kw at speed. The appeal of the servoprop is obviously being able to dial in the desired charging rate. Slight pitch for regen at high speed, a lot of pitch did one engine motor sailing, etc. 

Whether we achieve any of that is yet to be seen. 

If you can believe the material on Oceanvolt website and If you have a unit in each hull (i.e. 2 units) then it looks like 10kw is achievable at 13-14 knots.

servo_regen_2.gif

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2 hours ago, Wess said:

*  How light can you go on the outer skin before you start to have a significant risk of crushing and puncture damage in real life cruising environments?  If this isn't confidential and you can share, what is GB using (they seem to do OK in real life cruising environment) as an outer hull laminate?

Friend and I both have large-ish tris.  Mine more cruise orientated in design brief his more race orientated.  Both cored boats obviously.  His thermo-formed (? not sure that is the correct term?) mine w kerfs. We both have fairly light inner hull skins.  Both of us have had recent reason to do some hull repairs and we see well built boats.  My damage from massive lightning strike.  His from simple rock and roll while rafted to another boat and well secured and bumpered.  I would never in a million years think a bumper could this but he had some significant crushing (where the bumpers were) through the outer skin which looks to be carbon at a thickness equal to about 200-300 grams per square meter mat (and similar inner).  My outer hull laminate is more beefy.  

So back to the question... at what stage do you start to worry the outer hull is too thin/light for real life boating? 

Hi Wess

It depends on the size and purpose of the boat, even in CE you get different design categories that drive structural engineering. I can tell you that our size of boats, built to CE, have to have 1200g/sm skins (that is 1.2mm) on the outside skin. I would never want to go under 1000g for real protection for a 'big' cruising boat. If your buddy has 300g skins, that will hold the boat together, but impact or dock rash strength is very little, so he better baby that boat as much as possible, because: sh!t happens and that is why CE (Really, ISO Structural Cat A) have these rulebooks, written on top of the graves of plenty of people who kept pushing the limits.

It isn't a raceboat, which means the payloads are huge and the normal use cases can be wildly varying especially considering there aren't always pro sailors managing the boat... or perhaps because pro sailors do get to play on board... Safety factors are important ;). Case in point:  many old Gunboats have completely new rig packages and much much longer daggerboards and are being sailed harder than ever. Then 3Di sails and non-stretchy  running rigging came on board which recently meant the gear like mainsheet cars were blowing up. The boats are holding together though and a big part of this is due to weight-saving refits over the years - and safety factors!

This isn't an ideal situation though, so that is why the Gunboat 68 was engineered for worst case daggerboard, rudder and rig loads. Someone can take Dash and turn it into Condor without worrying about the platform, bearings, etc. I look forward to seeing this consistency or dare I say "one design" proving itself valuable in the years to come! 

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On 9/20/2019 at 4:08 AM, Greenflash said:

Hey you guys ARE smoking something - love these ideas! Yeah the glue down panels I am guessing lose 10-15% compared to raised /cooled panels, but they are walk-on and super easy to install and integrate. Water cooling in roof is doable, you are on a sandwich panel one side of foam, so you'd need to prep the water grid recesses in the mold before starting the roof. These will make the roof a lot heavier not even to speak of the water cooling system weight. Then the install complexity and the risk of leaks. Is the cost and sailing performance loss worth a 10% gain on solar? I'd rather spend that on bigger more efficient alternators or hydrogenerator integration etc etc. So short answer is - yes it can be done and we absolutely can do it - but I don't think it is money and weight well spent. 

Back from 2 successful boatshows, couple of little awards under the belt and fantastic feedback on the Gunboat 68. I was so busy I didn't take many photos but Sailing Yacht TV did a live walkthrough in Cannes, check it out below. Reminder: This is 6802 DASH, full cruising setup. 

 

All this robot talk has distracted us from this gem. There are so many amazing details incorporated into this boat I think I need to watch the video 2-3x times to take it all in. I will never have enough money to own a Gunboat, but when to notch designers get together with expert builders and experienced sailors great ideas happen and those will trickle down.

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3 hours ago, KC375 said:

If you can believe the material on Oceanvolt website and If you have a unit in each hull (i.e. 2 units) then it looks like 10kw is achievable at 13-14 knots.

servo_regen_2.gif

ok.  I was talking about only one prop.  

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Thanks Sam, Soma and Flash.  Much appreciated.  Was surprised to see skin this thin on a boat that big (not mine).  It is fast though LOL!

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22 hours ago, Greenflash said:

Hi Wess

It depends on the size and purpose of the boat, even in CE you get different design categories that drive structural engineering. I can tell you that our size of boats, built to CE, have to have 1200g/sm skins (that is 1.2mm) on the outside skin. I would never want to go under 1000g for real protection for a 'big' cruising boat. If your buddy has 300g skins, that will hold the boat together, but impact or dock rash strength is very little, so he better baby that boat as much as possible, because: sh!t happens and that is why CE (Really, ISO Structural Cat A) have these rulebooks, written on top of the graves of plenty of people who kept pushing the limits.

It isn't a raceboat, which means the payloads are huge and the normal use cases can be wildly varying especially considering there aren't always pro sailors managing the boat... or perhaps because pro sailors do get to play on board... Safety factors are important ;). Case in point:  many old Gunboats have completely new rig packages and much much longer daggerboards and are being sailed harder than ever. Then 3Di sails and non-stretchy  running rigging came on board which recently meant the gear like mainsheet cars were blowing up. The boats are holding together though and a big part of this is due to weight-saving refits over the years - and safety factors!

This isn't an ideal situation though, so that is why the Gunboat 68 was engineered for worst case daggerboard, rudder and rig loads. Someone can take Dash and turn it into Condor without worrying about the platform, bearings, etc. I look forward to seeing this consistency or dare I say "one design" proving itself valuable in the years to come! 

Have you considered Kevlar reinforcement? Marsaudon offers it as an option for the TS line.

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2 hours ago, Mordoc said:

Have you considered Kevlar reinforcement? Marsaudon offers it as an option for the TS line.

A number of years ago hybrid laminates were all the rage - 900grams of carbon and then 300g of kevlar or eglass. I can't dispute that the last 300g in kevlar would handle dock-rash better, but it is absolutely just going along for the ride. VPLP told us why put something in there that doesn't DO anything to the stiffness of the boat? It is like making a rope out of Dyneema and Polyester strands - the Dyneema will take all the load to failure before the PE even gets close to its max strain. 

So on the Gunboat 68, because in essence it is already beefed up by minimum skin thickness requirements for CE, we go full carbon because it actually does make the boat better, without taking away from the robustness in terms of impact strength. 

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30 minutes ago, Greenflash said:

 

So on the Gunboat 68, because in essence it is already beefed up by minimum skin thickness requirements for CE, we go full carbon because it actually does make the boat better, without taking away from the robustness in terms of impact strength. 

Indeed, I prefer a stiff boat even if it's a little noisier.

I'm a greenie, but am still a fan of a diesel for propulsion. Main reason is that the density of batteries does not equal that of diesel. I think that retracts on a cruising boat can be problematic. Watt & Sea's are what's going on the next boat. Will have two of them. I know that Greenflash is a fan of the units. Plus if they hit something, they pop up (most of the time)

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16 minutes ago, mpenman said:

I know that Greenflash is a fan of the units

Ya got me mate. They aren't the highest energy and not the final solution to this regen story but they work well, completely detachable and serviceable and don't hurt the boat if the get hit or if they break. A safe go to add on option for diesel propulsion boats. 

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On 3/21/2019 at 10:49 AM, Greenflash said:

...Thank you to everyone who contributed to this moonshot, even guys like you on these forums, we do try to listen and learn and aren't afraid of -constructive- criticism. 

...Czone setups and tank calibration that takes a little longer on the first boat.

  • ...We offer a rotating mast on the regatta rig version because those owners really care about the extra power you can generate in the main. ...[and] if pressed we can do a standard rig rotating. 
  • ...I will just remind everyone that Gunboat at its core is a cruising boat.
  • ...We also do a remote which puts the traveler and mainsheet in your hands.
  • ...A year or so ago Hall pushed us to consider their newest in-boom furling systems but we haven’t seen them live long enough without issues to be comfortable.
  • Greenflash

 

Let's review:

-Gunboat actively solicits feedback, likes suggestions and reads the ideas and comments in this topic on this forum.

-Gunboat offers rotating masts and will include a boom furler on owner's request (probably sooner than later). And I was criticized and personally attacked for raising the topic, more than once.

-Gunboat offers a 400+ lb remote controlled, programmable, self-powered and customized propeller in a dedicated hull compartment in the front of the left hull on GB68. And I was criticized and personally attacked for speculating about future designs doing much the same for regen.

-Gunboats come pre-designed to accommodate a Czone system.

-A small group on this topic who can't refute much of anything intelligently and so have to resort to personal attacks don't understand the literal definition of robot ("A robot is a machine—especially one programmable by a computer— capable of carrying out a complex series of actions automatically.") Let's call them 'the 3rd grade brigade.' And let's refer them to Ray Bradbury from 1950: There Will Come Soft Rains where indeed, a remote controlled garage opener would be robotic... 

-Gunboat currently offers a remote to control both mainsheet and traveller. Yeah, that's some classic salty greybeard sailing, right...

-There is an acronym the 3rd grade brigade probably isn't familiar with: IOT. They should check it out. I'm not sure which hull number of GB68 will have an owner who can tap his smartwatch, and have the autopilot activate, head the boat into the wind, and hold it there, but it won't be long. CZone can probably already do that on hulls 01 and 02 from a wireless pad. Making the GB68 really one big robot either already, or in the very near future.

-Not sure I remember this right, but I think the inefficiencies in asking a propeller design to work effectively in both forward and reverse made the first generation of props on Torquedo's Moonwave Gunboat testbed a rotating pod drive (blades could be designed for one direction only). They seem to have given that up, but Volvo Penta now has a two axis forward facing drive with adjustable angle of thrust, and a successful line of pod drives, so incorporating one more break in the drivetrain to retract the blades and change them out doesn't seem impossible (just heavy, but again, the bow thruster is 400+lbs and the Volvo systems are designed for power boats, so the weight could probably come down).

I talked with Stan Honey and Chris Anderson about marine applications / startups after a presentation they gave and it was interesting. One of the strong points they made was that most civilians weren't at all familiar with the tech breakthrough that made cell phones as potent as they are, and it's dirt cheap yet effective sensors. You can load tiny sensitive cheap sensors anywhere and send data to a controller for diagnoses / control functions. Combine this with cheap customer designed motherboards, and open source software, and you get the world we live in where kids are designing and programming their own drones not to fly remotely, but to fly in competitions where they have to take off, navigate a course, return and land autonomously.

Yeah, marine environments are harsh, salt water is corrosive, vibrations are a killer, but my money is on innovation to win in the long run. A green gunboat is coming, and it's going to be a big robot. I'm not evangelical about this, just realistic. I personally wouldn't want anything on board that didn't have a manual backup, which is one reason I'm still on the fence re Czone. (The third grade brigade probably has zero conception of Czone capabilities, now or in the future, and will respond with another fleshlight video or attack from a dummy account [from 'jedi,' who has 1 post. Really?]. And I'm the one pissing in the pool?) What about it, Greenflash? Czone probably has one master controller. What happens on a 68 should it conk out? I'd love to know more about the setup.

A MUCH better criticism of future robotic tech that will inevitably find its way on to future Gunboats can be found in this tweet I saw just yesterday: Hard to imagine a worse job than truck "safety driver".

At what point does the human become a maintenance servant to the robot(s)? Tech doesn't have a good record at promising to relieve labor but costing more human time and effort than before the innovation. Monkey can give us his perspective as he 'cares' for robots professionally. I'm a gearhead and wouldn't mind doing a good bit of my own maintenance if I owned a 68, and keeping an eye on too much computerized software integrated into hardware would have a line I wouldn't want to cross, but I have faith in remote diagnosing from error codes and sensors and even, to a greater extent than a modern car, my ability to pull a part and replace it.

 

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Oh yeah, and what is the state of fueling a boat these days? I always imagined a system where one could strain the diesel coming from the pump BEFORE it got into one's tanks. That would be a great help, but not practical as any effective strainers would slow down the fueling too much. Any new products that can do anything similar? Polishing the fuel while pumping? I'm guessing no...

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9 minutes ago, dcnblues said:

Oh yeah, and what is the state of fueling a boat these days? I always imagined a system where one could strain the diesel coming from the pump BEFORE it got into one's tanks. That would be a great help, but not practical as any effective strainers would slow down the fueling too much. Any new products that can do anything similar? Polishing the fuel while pumping? I'm guessing no...

Image result for baja marine fuel filter

    Use your imagination! 

 

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3 minutes ago, Rasputin22 said:

 

    Use your imagination! 

 

Umm, is it a sex toy?

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It may as well be for you if you can't put the last two responses to your comment about 'filtering diesel BEFORE it goes into the tank'...

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Yeah, but are they worth a damm, which is what I asked, or are you just attacking me again? Oh wait, I keep forgetting I'm the one who's pissing in the pool.

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32 minutes ago, dcnblues said:

Yeah, but are they worth a damm, which is what I asked, or are you just attacking me again? Oh wait, I keep forgetting I'm the one who's pissing in the pool.

How am attacking you? You 'imagined' something that has been around for decades and longhy identified the name of the item for you and I offered a photo as well and you respond with asking if it was a sex toy? Must be Happy Hour once again at your house. Now that was a snide bit of a comment but well deserved if you keep this sort of stuff up. 

    Where did you ask if the Baja Filter was 'worth a damm(sic)'? Lose the attitude and you might find readers here can be very helpful but not at the rate you are going.

https://lmgtfy.com/?q=do+baja+filters+strain+fuel+effectively%3F

 

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I have seen Baja filters with 4 consecutive filter walls, separated into  3" wide  cells, with 1/2" high sills to hold back water. Pretty damn effective, with a fairly high flow rate.

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2 hours ago, dcnblues said:

attack from a dummy account [from 'jedi,' who has 1 post. Really?].

I'm not a dummy account. This was the first thread I've actually read on this site, and I happen to like it so I started an account. Like most, I'm appreciative of the Gunboat insiders actually taking the time to comment here, and think its rude and inconsiderate to fuck up the thread with your bullshit so I said something. This is the last time I'll respond to you, since you called me out specifically I figured I'd give my .02.

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1 hour ago, longy said:

I have seen Baja filters with 4 consecutive filter walls, separated into  3" wide  cells, with 1/2" high sills to hold back water. Pretty damn effective, with a fairly high flow rate.

Thank you.

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2 hours ago, Rasputin22 said:

 Use your imagination!

 

1 hour ago, Rasputin22 said:

How am attacking you?

But I'm the one pissing in the pool.

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2 hours ago, dcnblues said:

But I'm the one pissing in the pool.

Yes you are.  Actually doing something innovative is not the same thing as having an idea.  It's much, much, much harder.  The reason people are pissing on your ideas isn't to be disrespectful (at least it wasn't to start with), it's because they've thought about them more deeply than you, or even tried some of them themselves, and seen where and how they fail.  

You're getting into arguments with people who know a lot more than you do, and rather than do the hard thing (actually building something that works) you take offense at their (sometimes not sugarcoated) advice.  No I'm setting you to ignore to clean up this otherwise great thread.  

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12 hours ago, Greenflash said:

A number of years ago hybrid laminates were all the rage - 900grams of carbon and then 300g of kevlar or eglass. I can't dispute that the last 300g in kevlar would handle dock-rash better, but it is absolutely just going along for the ride. VPLP told us why put something in there that doesn't DO anything to the stiffness of the boat? It is like making a rope out of Dyneema and Polyester strands - the Dyneema will take all the load to failure before the PE even gets close to its max strain. 

So on the Gunboat 68, because in essence it is already beefed up by minimum skin thickness requirements for CE, we go full carbon because it actually does make the boat better, without taking away from the robustness in terms of impact strength. 

Not just dock-rash but crash resistance. Kevlar is more absorbent than carbon or graphite. They used to weave the mats into tennis racquets when they were getting a handle on things.

Anyway, I'm interested in why you, or VPLP, say that Kevlar is just a passenger. If you're saying ultimate race boat stiffness/weight is the goal I get it, but in a race/cruise design, some level of crash resistance is good to. Kevlar, as it is absorbent(or can absorb when in tension with other skins), can be woven into carbon to add an extra element of safety. (Maybe less relevant with the multi and basic GB design brief admittedly)

Here's the best explanation that I've come across for any S/V that's moving at a clip and should/might consider crash resistance as part of the design brief, from Bill Lee, reviewing the Bieker Riptide 55. (Ras, yes I remember another instance where I quoted this great review a while ago in another thread). 

http://svrocketscience.com/technical-details/

 

 

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This video does a fair job explaining the differences and reasons for different applications, from a race car perspective. I'm in the auto racing industry, we use kevlar mostly in aero parts, and carbon fiber for the body panels themselves. Things like winglets, diffusers, endplates etc., kevlar is really good. I'm not sure of the loads seen in boat building, but everything Greenflash said makes total sense for the thicknesses and ratings they're using.  

 

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Everything you guys say is absolutely right - Kevlar is of course better than Carbon for crash resistance - they make bullet proof vests out of the stuff! :P

Our conclusion was to use the minimum skin thickness requirement to benefit performance while understanding our heavy skins already gave us a huge margin of safety for impact strength, we then analyse what the crash event is doing. The vast majority of times it is from the front onto the bow or foils (and we discussed this in this thread before so please go back to check that out) - so we do a 4 level of safety which I will reiterate very shortly: A crash bow not integral to the hull skins and filled with pretty high density energy absorbing foam, then the actual hull closing out, then a crossbeam bulkhead a bit behind that, then the water tight aft sail locker bulkhead a few meters behind that. 

When I say Kevlar is going along for the ride, to be clear, it is not adding a significant value to the overall stiffness, but would add more impact resistance. We chose stiffness while being more than comfortable with impact loads due to the minimum skin requirements and 4-tier impact protection on bow and heavily reinforced daggerboard bearings etc.

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5 hours ago, Greenflash said:

Everything you guys say is absolutely right - Kevlar is of course better than Carbon for crash resistance - they make bullet proof vests out of the stuff! :P

Our conclusion was to use the minimum skin thickness requirement to benefit performance while understanding our heavy skins already gave us a huge margin of safety for impact strength, we then analyse what the crash event is doing. The vast majority of times it is from the front onto the bow or foils (and we discussed this in this thread before so please go back to check that out) - so we do a 4 level of safety which I will reiterate very shortly: A crash bow not integral to the hull skins and filled with pretty high density energy absorbing foam, then the actual hull closing out, then a crossbeam bulkhead a bit behind that, then the water tight aft sail locker bulkhead a few meters behind that. 

When I say Kevlar is going along for the ride, to be clear, it is not adding a significant value to the overall stiffness, but would add more impact resistance. We chose stiffness while being more than comfortable with impact loads due to the minimum skin requirements and 4-tier impact protection on bow and heavily reinforced daggerboard bearings etc.

Thank you for the very valuable info Greenflash! 

Re: "heavily reinforced daggerboard bearings" -> Have you considered centerboards?

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4 minutes ago, Mordoc said:

Thank you for the very valuable info Greenflash! 

Re: "heavily reinforced daggerboard bearings" -> Have you considered centerboards?

Ha! That's a good one!

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10 hours ago, fufkin said:

Not just dock-rash but crash resistance. Kevlar is more absorbent than carbon or graphite. They used to weave the mats into tennis racquets when they were getting a handle on things.

Anyway, I'm interested in why you, or VPLP, say that Kevlar is just a passenger. If you're saying ultimate race boat stiffness/weight is the goal I get it, but in a race/cruise design, some level of crash resistance is good to. Kevlar, as it is absorbent(or can absorb when in tension with other skins), can be woven into carbon to add an extra element of safety. (Maybe less relevant with the multi and basic GB design brief admittedly)

Here's the best explanation that I've come across for any S/V that's moving at a clip and should/might consider crash resistance as part of the design brief, from Bill Lee, reviewing the Bieker Riptide 55. (Ras, yes I remember another instance where I quoted this great review a while ago in another thread). 

http://svrocketscience.com/technical-details/

 

 

 

Fufkin, I’m not a materials engineer but have read up a bit on this stuff for my home project so I tried to find some of my original sources but couldn’t in a hurry. This is summary from memory. Others on this site are more expert than I so may elaborate (or correct me).

@Greenflash's analogy is key to why mixed fiber matrix has issues “It is like making a rope out of Dyneema and Polyester strands - the Dyneema will take all the load to failure before the PE even gets close to its max strain.”

@jedi's  video does a great job outlining the relative properties of different fibers.

Kevlar and Carbon have very different properties that mean they effectively act in sequence rather than together. The Carbon is stiffer and less stretchy than the Kevlar so it takes all the load at first as the Kevlar is just starting to stretch and not adding any stiffness when the Carbon is at max extension. Once the carbon breaks then the Kevlar stretches a bit more and starts to take the load. So you get the benefit of carbon until it breaks and then the benefit of Kevlar until it breaks. If you used just one material but a bit more you would be better than using both. Carbon would give you stiff but brittle. Kevlar more flexible but tougher. (There may be circumstances where you add one on the other. Forexample Kevlar is good at abrasion resistance so you might want to put selectively that on the outside as a protective layer if you anticipate rock rash - eg. Kevlar bow and keel strips on carbon canoes for white water. In this case the Kevlar "protects" the carbon but add no strenght or stiffness).

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Seems pretty straightforward. If the objective is to reduce the odds of hull penetration and water ingress, add Kevlar. You’ll still need to repair CF later.

If water ingress is not a mission-critical risk (because of watertight bulkheads etc), don’t bother with Kevlar and its added weight.

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12 minutes ago, EarthBM said:

Seems pretty straightforward. If the objective is to reduce the odds of hull penetration and water ingress, add Kevlar. You’ll still need to repair CF later.

If water ingress is not a mission-critical risk (because of watertight bulkheads etc), don’t bother with Kevlar and its added weight.

If your primary design criteria is avoiding hull penetration then probably you look at 100% Kevlar, very tough but not rigid.

If you are adding Kevlar to carbon for penetration resistance the question is how much penetration resistance does the Kevlar add compared to adding that equivalent effort, cost, weight by simply having a thicker carbon structure. From my reading the answer is usually for a given budget (time, $, weight) the answer is stick with more of one fiber.

At the extreme where people obsess over the full set of mechanical properties regardless of the $ e.g. the folks creating the driver survival cells used in F1 then they do use a sequence of materials with deformable structures to absorb energy and the equivalent of bullet proof vests to prevent penetration of things like carbon fiber shards.

As is obvious, this is not my area of expertise. I've played around with this stuff in building sports equipment (not sailing) and found a few thousand in consulting $ with a materials expert saved me more than that in wasted trial and error. (my final product was as good or better than the best commercial offering...with a financial cost of many times more...not to mention my time but then hobbies should not be measured that way).

I presume GB and others have done their homework with experts in the field.

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13 minutes ago, KC375 said:

If your primary design criteria is avoiding hull penetration then probably you look at 100% Kevlar, very tough but not rigid.

If you are adding Kevlar to carbon for penetration resistance the question is how much penetration resistance does the Kevlar add compared to adding that equivalent effort, cost, weight by simply having a thicker carbon structure. From my reading the answer is usually for a given budget (time, $, weight) the answer is stick with more of one fiber.

At the extreme where people obsess over the full set of mechanical properties regardless of the $ e.g. the folks creating the driver survival cells used in F1 then they do use a sequence of materials with deformable structures to absorb energy and the equivalent of bullet proof vests to prevent penetration of things like carbon fiber shards.

As is obvious, this is not my area of expertise. I've played around with this stuff in building sports equipment (not sailing) and found a few thousand in consulting $ with a materials expert saved me more than that in wasted trial and error. (my final product was as good or better than the best commercial offering...with a financial cost of many times more...not to mention my time but then hobbies should not be measured that way).

I presume GB and others have done their homework with experts in the field.

Layering of materials.  Intuitively makes sense to my Holiday Inn Express little grey matter orb but I don't think (?) anyone does it in the boating world.  Pretty sure they are all smarted than me but I wonder why not.

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1 hour ago, EarthBM said:

Seems pretty straightforward. If the objective is to reduce the odds of hull penetration and water ingress, add Kevlar. You’ll still need to repair CF later.

If water ingress is not a mission-critical risk (because of watertight bulkheads etc), don’t bother with Kevlar and its added weight.

I think the fact that it's only good in tension makes it only good for halyards, etc. I know that it would be nice to have a layer in there for when something makes a hole in the side of the boat if just to hold the broken bits together and it also has some sound deadening qualities. It's such a bear to work with that neither of those things would make me want to use the stuff. I heard also that the dry fiber will absorb lots of moisture. Is that true?

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     Kevlar does absorb water if the resin matrix is worn away or fractured. One of the reasons that Basalt fiber seems to be a good replacement or even Innegra (polyproprolene).  Both are far easier to work with too. The makers of Innegra just found an old textile mill to set up shop in right next to the US Army's helicopter training and Skunk Works in Ft Rucker AL.

    Innegra has shown great promise for body and airframe armor in the assault helicopters and they are hoping it will help the rotor blades against small arms fire. Whitewater canoe and kayak builders are loving Innegra and are glad to be rid of Kevlar at last!! 

    Give it a try Russ and give us a report!

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On 9/25/2019 at 10:38 AM, Greenflash said:

I can tell you that our size of boats, built to CE, have to have 1200g/sm skins (that is 1.2mm) on the outside skin. I would never want to go under 1000g for real protection for a 'big' cruising boat. If your buddy has 300g skins, that will hold the boat together, but impact or dock rash strength is very little, so he better baby that boat as much as possible, because: sh!t happens and that is why CE (Really, ISO Structural Cat A) have these rulebooks, written on top of the graves of plenty of people who kept pushing the limits.

Does anyone know what outer skins  Bieker 53 Fujin has?

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45 minutes ago, EarthBM said:

Does anyone know what outer skins  Bieker 53 Fujin has?

Custom Carbon Cat Cloth
By Dan Spurr, May 21, 2015
https://www.proboat.com/2015/05/custom-carbon-cat-cloth/

Quote

One key to success is selecting the right fabric for the job. Steggall says he uses no woven reinforcements, only noncrimp stitched fabrics. He worked with Formax to modify its +45°/–45° biaxial carbon fiber fabrics of 400 g/m² and 300 g/m² (1.4 oz/sq ft and 1 oz/sq ft) and a 0°/90° biaxial of 300 g/m². A nylon microweb (at about 3 g/m² per 100 g/m² of carbon) was stitched between the plies to provide a path for air to escape. This web also increased flexural and compression strength without adding significant weight. In the end, the tests proved that infusion would best meet Bieker’s specifications.

 

P.S.  This is interesting too:

Fujin: The inside story of this carbon catamaran’s Caribbean refit
https://www.yachtingworld.com/extraordinary-boats/fujin-carbon-catamaran-caribbean-refit-122957

Quote

In a testament to the original build, structurally Fujin was in good shape post-capsize but every other aspect of the boat was in ruin. “The boat was a mess when it came up,” recalls Gina. “The most shocking thing was the weed. There was a high volume of it in every corner. We were scooping it out in armfuls.

“We managed to salvage the winches by stripping and removing them the second Fujin was righted, but everything else was pretty much destroyed. The deck gear was corroded, all electrics, interior furnishings and the engines needed to be replaced.”

 

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11 hours ago, KC375 said:

 

Fufkin, I’m not a materials engineer but have read up a bit on this stuff for my home project so I tried to find some of my original sources but couldn’t in a hurry. This is summary from memory. Others on this site are more expert than I so may elaborate (or correct me).

@Greenflash's analogy is key to why mixed fiber matrix has issues “It is like making a rope out of Dyneema and Polyester strands - the Dyneema will take all the load to failure before the PE even gets close to its max strain.”

@jedi's  video does a great job outlining the relative properties of different fibers.

Kevlar and Carbon have very different properties that mean they effectively act in sequence rather than together. The Carbon is stiffer and less stretchy than the Kevlar so it takes all the load at first as the Kevlar is just starting to stretch and not adding any stiffness when the Carbon is at max extension. Once the carbon breaks then the Kevlar stretches a bit more and starts to take the load. So you get the benefit of carbon until it breaks and then the benefit of Kevlar until it breaks. If you used just one material but a bit more you would be better than using both. Carbon would give you stiff but brittle. Kevlar more flexible but tougher. (There may be circumstances where you add one on the other. Forexample Kevlar is good at abrasion resistance so you might want to put selectively that on the outside as a protective layer if you anticipate rock rash - eg. Kevlar bow and keel strips on carbon canoes for white water. In this case the Kevlar "protects" the carbon but add no strenght or stiffness).

KC, I'm not a materials engineer either and your description of Kevlar roughly meshes (pun intended) with my understanding. I kind of visualize Kevlar as being a 'membrane' in relation to Carbon. I'm gonna cite the relevant sections of the Bill Lee article that I linked above. There's an interesting tidbit about Kevlar being on the interior of the lay up as opposed to the exterior.

11 hours ago, EarthBM said:

Seems pretty straightforward. If the objective is to reduce the odds of hull penetration and water ingress, add Kevlar. You’ll still need to repair CF later.

If water ingress is not a mission-critical risk (because of watertight bulkheads etc), don’t bother with Kevlar and its added weight.

EarthBM, this is kind of what I thought. I really don't have a handle on the extra weight that an extra lay up of Kevlar would add(as in the choices made for the GB) and yes, the Kevlar lay up could/should be specified just for certain crash prone sections (bow(s) and leading edge of the keel in the case of a mono). 

 

Anyway, here's an excerpt from the Bill Lee article on the Bieker designed  S/V Rocketship(link to full article up thread) probably designed over 20 years ago at this point,  so maybe some thinking has changed...or maybe not...and yes, the design brief is somewhat different than the GB62...

"What was apparent from the polar predictions was the extreme speeds that a
yacht like the Riptide 55 can generate. For this reason it was decided not
to use the ABS guidelines for yachts, those standards did not adequately
address the speed potential of today’s modern craft. Instead the standards
selected were ABS slamming standards for high speed military craft and Det
Norske Veritas standards for high speed offshore motor craft. Using these
standards a loading of 7.5 PSI was arrived at, approximately double ABS
standards. To put this number into perspective, the RT55 could slam on an
area of a little over a square meter in front of the keel for the life of
the boat. These are extreme conditions found when flying off of waves in
the worst conditions. In order to keep the panel from flexing and to
provide fatigue resistance the panel specification was set at 40 PSI so
that the maximum loading was not to exceed 20% of the panels specified
breaking strength. A laminate schedule was modeled in the computer and
then panels were made by the builder and tested by Gugeon Brothers to see
if they met the specifications. The panel for the hull bottom has a core
of 1″ Baltec Duracore and skins of carbon fiber and unidirectional glass.
Upon testing of these panels a breaking strength of 54 PSI was found, well
in excess of the 40 PSI specification and a number realized only in high
speed power craft. Even more important in a panel test of 400,000 flexing
cycles of 25 PSI ( half the panels breaking strength and over three times
the required extreme specification) no softening was found. This is
unprecedented. The next time a manufacturer makes claims about their
hull’s strength ask to see the documentation for the underlying
engineering assumptions, the finite element analysis and the panel testing
data to back up the assumptions in the finite element analysis.
The question becomes why make the panel so strong. The answer is that the
panel had not only to sustain the slamming conditions at sea but with all
the debris in the modern ocean it had to be able to sustain a collision
with a solid object such as a log or a cargo container that had been lost
off of a deck of a ship. Keep in mind that the RT55 is capable of speeds
over 20 knots. The deceleration from such a hit would be dangerous enough
without having to worry if the boat would disintegrate. As further
protection from such a catastrophic situation a kevlar crash barrier
laminate was added in the center 30 inches of the hull forward of the
keel. This laminate is next to the core on both sides underneath the
carbon fiber. This is counter to present conventional thinking which would
put the kevlar on the outer laminate because of its abrasion resistance.
What was found in the panel testing at Guegon was that the kevlar in a
catasrophic hit would shatter on the outside skin because of its
brittleness and the stiffness of the underlying core and laminates and
even potentially holed. Dropping heavy metal balls on the laminate it was
found that while the glass and carbon skins were breached that the
laminate hung together because the kevlar as the last line of defense
works in tension to absorb the energy of the of the object and while
delamination occurred the laminate was not breached. As a belt and
suspenders approach to hull integrity, integral sewage, fuel and water
tanks form a double bottom..."

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I've added kevlar to motorsport racing parts as well.....   mostly exterior aero parts as they get trashed quite a bit and having your parts remains linked together when the carbon explodes is good at not having parts slung all over the track.

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Was thinking about the crash structure on the bow of the 68, was the reason that it isn't made out of Kevlar, considering Kevlar is better at absorbing an impact, due to the different expansion rates that might ruin the paintwork? 

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On 9/27/2019 at 3:49 PM, EarthBM said:

Seems pretty straightforward. If the objective is to reduce the odds of hull penetration and water ingress, add Kevlar. You’ll still need to repair CF later.

If water ingress is not a mission-critical risk (because of watertight bulkheads etc), don’t bother with Kevlar and its added weight.

Put a layer of Kevlar at the inside of crash zones, to keep the "trash" together and avoid water ingress, sounds like a smart idea to me.

Does anybody know how Marsaudon is doing iit?

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On 9/27/2019 at 7:23 PM, ProaSailor said:

One key to success is selecting the right fabric for the job. Steggall says he uses no woven reinforcements, only noncrimp stitched fabrics. He worked with Formax to modify its +45°/–45° biaxial carbon fiber fabrics of 400 g/m² and 300 g/m² (1.4 oz/sq ft and 1 oz/sq ft) and a 0°/90° biaxial of 300 g/m². A nylon microweb (at about 3 g/m² per 100 g/m² of carbon) was stitched between the plies to provide a path for air to escape. This web also increased flexural and compression strength without adding significant weight. In the end, the tests proved that infusion would best meet Bieker’s specifications.

This is a good bit of boatbuilding debate, as pertinent to crash protection as Kevlar vs Carbon is. Firstly some info: Stitched fabric is a bit lighter and stiffer than woven fabrics because the woven weave absorbs slightly more resin and the "rovings/strands" of material need to go up and down through the weave, where a flat stitched fabric has strands that are completely straight. 

However on cruising boats we have always used a woven fabric as the first layer down on the mold because, apart from some sanding-and-painting benefits and it printing less, it holds together in a crash. If you had a small to medium sized hole in the outer skin on a stitched boat, the water will actually 'tear' the strands off and apart.. and keep going all the way down the undamaged hull - they are completely relying on inter-laminar shear, whereas a woven fabric is mechanically holding itself together. 

Also, from the many panels I have seen tested I am pretty sure woven generally handles impact loads better than stitched. (In other words in a bowling-ball drop test). I'll let you composite guru's comment on that. 

For the quoted project, the micromesh fibers assisted with infusion flows but also added strength. I don't know how they would help with 'peeling' of fibres after impact.  My comments above are based solely on pure woven vs pure stitched carbon cloth. Another thing to consider ;)

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On 9/27/2019 at 9:01 PM, fufkin said:

This is counter to present conventional thinking which would
put the kevlar on the outer laminate because of its abrasion resistance.
What was found in the panel testing at Guegon was that the kevlar in a
catasrophic hit would shatter on the outside skin because of its
brittleness and the stiffness of the underlying core and laminates and
even potentially holed. Dropping heavy metal balls on the laminate it was
found that while the glass and carbon skins were breached that the
laminate hung together because the kevlar as the last line of defense
works in tension to absorb the energy of the of the object and while
delamination occurred the laminate was not breached.

My Crowther cat bulit in '91 is kevlar inner skin, divinycell core, and glass exterior skin (West epoxy).  A drunk ponga driver put his prop into my hull in Panama a couple years ago.  It cut clean through the outer skin and foam, but didn't penetrate the Kevlar inner skin.

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Just found this little vid, the production values may not be ideal, but still nice to see some of the details and talk about the design. 

 

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1 hour ago, Lat 18 said:

Five Gunboats hauled at Newport Shipyard right now, including the 68 and the 90.

Six if you include the 57 in the tent.

 

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As the boat in the tent is not a Gunboat then that would add up to 5 Gunboats in Newport Shipyard.

 

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47 minutes ago, Muff said:

As the boat in the tent is not a Gunboat then that would add up to 5 Gunboats in Newport Shipyard.

 

"if" being the pivotal word...….

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I believe there is a separate page for that custom project? Not sure it has anything to do with the 68 forum?

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On 10/19/2019 at 11:42 AM, spike said:

Six if you include the 57 in the tent.

 

Opps, you're right. Forgot about Soma's project.

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9 hours ago, Lat 18 said:

Opps, you're right. Forgot about Soma's project.

What is happening with that....?   money issues..?  Why is it not a Gunboat..?

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3 hours ago, PIL66 - XL2 said:

What is happening with that....?   money issues..? 

We are on pause until spring. Boss needs to concentrate on work for a bit.

3 hours ago, PIL66 - XL2 said:

Why is it not a Gunboat..?

It IS a Gunboat, it's just Muff''s opinion that it isn't. Luckily Muff's opinion isn't relevant.

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7 hours ago, soma said:

We are on pause until spring. Boss needs to concentrate on work for a bit.

It IS a Gunboat, it's just Muff''s opinion that it isn't. Luckily Muff's opinion isn't relevant.

I bet Gunboat will claim it when it starts smoking 60's in regattas.... ;)

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Look guys and gals, Gunboat aren't involved in the "soma project" so really can't comment - there's a thread for that if you feel like it - what I can do is stick to the thread and update you all on the progress at the Gunboat 68 factory! 

  • GB6802 Dash has been back in the marina for some final hitlist items and leave for their crossing next week.
  • GB6803 Deck was dry fitted
  • GB6804 Was demolded and...
  • Starting GB6805 in a couple of weeks once the mold is prepped!

Check out the link for more info: https://www.gunboat.com/gunboat68-on-a-roll/

 

2019-10-24_11h53_19.png.9be64d3948b60f170569c2b30599aae1.png

2019-10-24_11h53_34.png.7f8ab214d0b7d8ff72a9a38f6fd25941.png

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Oh damn, that carbon in the sunlight... Absolute pornography!

Thanks for the update Greenflash! :)

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Nice to hear that #5 is in the pipeline, what with all the doom-and-gloom around the state of things at Gunboat. Congratulations on your success thus far, hopefully it will continue. It's a beautiful boat!

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15 hours ago, jordanseriesdrogue said:

Saw yacht Condor at Newport Shipyard Nov. 2nd.

Both hulls partially shrink wrapped. 

To protect?

Probably getting the bottom done

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On 10/24/2019 at 5:57 AM, Greenflash said:

Look guys and gals, Gunboat aren't involved in the "soma project" so really can't comment - there's a thread for that if you feel like it - what I can do is stick to the thread and update you all on the progress at the Gunboat 68 factory! 

  • GB6802 Dash has been back in the marina for some final hitlist items and leave for their crossing next week.
  • GB6803 Deck was dry fitted
  • GB6804 Was demolded and...
  • Starting GB6805 in a couple of weeks once the mold is prepped!

Check out the link for more info: https://www.gunboat.com/gunboat68-on-a-roll/

 

Damn fine looking hulls there. Good to see you selling boats. I'd have no hesitation with a 68 with Greenflash in the mix. I think that Soma would agree on that matter. Boats are very, very dependent on the person overseeing the build. 

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2 hours ago, mpenman said:

Damn fine looking hulls there. Good to see you selling boats. I'd have no hesitation with a 68 with Greenflash in the mix. I think that Soma would agree on that matter. Boats are very, very dependent on the person overseeing the build. 

Green flash is the man. I don't know how he does it. The patience of a saint!

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Gosh guys, thanks. A couple of years in china will ram that patience into you good and and solid. No cliches intended but I am really just a small part of a big team, long ago I realized I am not VERY good at anything, but pretty good at a lot of things so I try to just help all the guys smarter and better than me do their jobs as best they can. Some amazing people here, they are killing it. Lots more work to do and improvements to make. No rest for the wicked! 

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So I've seen "removable seats and tillers" mentioned a few times in Gunboat marketing stuff and articles.

Does anyone have a picture of what that setup actually looks like? I haven't seen a picture of it.

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2 hours ago, eastern motors said:

I'm sure it's the same as the Outremmer 5x.  Same parent company.  Look up some youtube videos of that boat.

Nope! ;) they are custom designed Carbon seats, quick release bases and the seat can rotate. Custom square-to-round style carbon tillers. We still have some tweaks to do on Condor, but getting there. aecb0b9d-83e3-4af5-959f-5728f34f541f.thumb.JPG.43859dd3366c5b539dcce5ca8e1acd12.JPG

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