GB5508 Rebuild - Soma's Project

MR.CLEAN

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If the builder can't get a bond, you have to ask yourself why not - and then run away!
This!

Adding that there are alternatives that may work better than a bond in some situations.  

And at the end of the day, all your careful negotiation may be worthless if they just go belly-up, so do your due diligence (or pay someone to do it for you) if you're spending millions of dollars on anything!  For some reason, businessmen and lawyers who know better seem to forget all the rules when it comes to their passion. 

 

Wess

Super Anarchist
soma said:
Weight IS a factor in the gelcoat vs paint debate, but the bigger issue is the resin choice that gelcoat demands. Gelcoat is polyester, meaning the whole boat has to be built in polyester/vinylester. No epoxy construction. That is a big technological step back if you're trying to build a light, stiff, carbon boat. That's not to say that vinylester/polyester boats can't be fast, but you DO give up a lot performance-wise (extra weight/decreased stiffness). Also, gelcoat comes in very basic colors. No sexy metallics with gelcoat.

During the design phase of the 68 some members within the group kept mentioning gelcoat. We tried to squash that debate right away. Gunboats just should be epoxy boats.

For your purposes, though, I'd think that a vinylester/gelcoat boat would be the way to go (if you were designing a custom production boat). I think it's safe to say that fairing/painting represents a 20% price premium over gelcoat. Epoxy, as well, represents a huge price increase compared to vinylester (though the % of the total cost of the project is tiny).

I think about weight savings a lot, and how every gram adds up. Chase every gram. If you flip the debate, though, and chase cost then there are a LOT of ways to save a lot of money. Fiberglass ($) vs carbon ($$$), infusion ($) vs wet-layup ($$$), gelcoat ($) vs paint ($$$), vinylester ($) vs epoxy ($$$), foam ($) vs nomex ($$$). I think that's where the TS guys have it right. Spend on the stuff that matters, save everywhere else. Yeah, you may be giving up 5% on the performance, but it frees up a lot of money to spend elsewhere to get that performance back. And you'll sell a helluva lot more boats. :) Gunboat have sold 2 boats in the time it's taken TS to sell 30.
Thank you; very helpful.

Am I correctly recalling that one GB (55?) got a wrap? And if yes, how did that hold up?

 

Whiskey.T

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soma said:
Fiberglass ($) vs carbon ($$$), infusion ($) vs wet-layup ($$$), gelcoat ($) vs paint ($$$), vinylester ($) vs epoxy ($$$), foam ($) vs nomex ($$$).
Wait, maybe I'm misunderstanding something,  is wet-layup better than infusion? For all the other items you mentioned, the expensive option is obviously better (other than price), hence the trade-off, but I thought infusion meant less resin, better resin/fiber ratio, less weight, etc.?? 

 

mad

Super Anarchist
soma said:
Infusion is super heavy. It's cheap and fast. But it ain't light.
You can split the build process and avoid the excess weight gains, you can achieve very good skin/resin ratios, it’s the core bonding with infusion that adds to the weight, however it comes down to $$$$ as always. 

It’s a constant juggling game, as we all know. 

 

Student_Driver

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Adding that there are alternatives that may work better than a bond in some situations.  
Could you create a legal structure where an LLC or Corp entity could own the work in progress including the hull, purchased parts etc? The builder could have a contract with the llc to perform work etc. The LLC could buy parts and materials directly and/or the builder could be paid monthly based on work done (man hours) and parts needed for next months work etc. If the builder goes belly up, you'd own the LLC including all of the work and inventory of parts and materials etc.  

 

HotCarNut

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Denver, CO
Could you create a legal structure where an LLC or Corp entity could own the work in progress including the hull, purchased parts etc? The builder could have a contract with the llc to perform work etc. The LLC could buy parts and materials directly and/or the builder could be paid monthly based on work done (man hours) and parts needed for next months work etc. If the builder goes belly up, you'd own the LLC including all of the work and inventory of parts and materials etc.  
This seems like a logical way to approach a custom build.  Not sure if production builders would be willing to go that route....

 

us7070

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Could you create a legal structure where an LLC or Corp entity could own the work in progress including the hull, purchased parts etc? The builder could have a contract with the llc to perform work etc. The LLC could buy parts and materials directly and/or the builder could be paid monthly based on work done (man hours) and parts needed for next months work etc. If the builder goes belly up, you'd own the LLC including all of the work and inventory of parts and materials etc.  
that doesn't solve the problem i mentioned above...

Without an operating business to finish the boat.., all you own is a pile of parts - and they are not worth nearly what it cost you to build them.

the yard is shut.., all the craftsmen who know how to build your specific type of boat are gone to various new jobs.., what if you still need some parts made up - say, the deck...? where is the mold? are you going to be able to get it and bring it to a new yard and say "hey.., make my deck for me'?

the guys who built the last version of your boat to be completed.., who know how to build your boat without figuring it out from scratch - the cabinetry.., the wiring.., the plumbing.., are all gone. 

you either buy the company.., keep the employees with all the institutional knowledge.., keep all the tools.., and so on.., or you sell your parts for 10 cents on the dollar

 
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harryproa

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soma said:
Infusion is super heavy. It's cheap and fast. But it ain't light.
It's only heavy if the infusion is done badly.  If there are no gaps between core panels, the core is flat, simply curved or heat bent (ie, not contour cut) and the edges treated so there is no accumulation of resin then 2:1 fibre:resin is a given.   Consequently, it is only "cheap and fast" if the hulls shapes are simple.  Lots of cored compound curves really slow things down.  

The resin saved over hand laid (vac bagged or not) is huge, as is the weight.  The ability to finish all the edges, add rebates, solids, joins and extra reinforcing gives further weight savings.  For most builders, the biggest deal is the ability to get everything in the right place, without the stress of racing against the resin curing.  The near zero contact with sticky resin or fibreglass makes for far fewer stuff ups, poor laminates and sick builders.     see http://harryproa.com/?p=1845 .  

The infused 20m/66'ter at http://harryproa.com/?p=726 is on target to be cruise ready at 4,000 kgs/4 tons displacement.

Epoxy is now so close to the price of vinylester (both under $Aus10/$US7) that there is effectively no difference.  

 
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trackday

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It's only heavy if the infusion is done badly.  If there are no gaps between core panels, the core is flat, simply curved or heat bent (ie, not contour cut) and the edges treated so there is no accumulation of resin then 2:1 fibre:resin is a given.   
2:1!? By volume or weight?   Carbon or glass?

Most carbon race boats shoot for 35 +/- 1% resin by weight in a prepreg laminate.  Are you suggesting that 15% more resin by weight in a carbon laminate is acceptable for a performance boat?  Perhaps I am misunderstanding your statement.  

 

Airwick

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Victoria, BC
It's only heavy if the infusion is done badly.  If there are no gaps between core panels, the core is flat, simply curved or heat bent (ie, not contour cut) and the edges treated so there is no accumulation of resin then 2:1 fibre:resin is a given.   
2:1!? By volume or weight?   Carbon or glass?

Most carbon race boats shoot for 35 +/- 1% resin by weight in a prepreg laminate.  Are you suggesting that 15% more resin by weight in a carbon laminate is acceptable for a performance boat?  Perhaps I am misunderstanding your statement.  
I read this to mean 2 parts fibre 1 part resin or 33.33% resin so you guys appear to be in "violent agreement"...

 

Zonker

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soma said:
Gelcoat is polyester, meaning the whole boat has to be built in polyester/vinylester. No epoxy construction
Does anybody have any positive experience with the gelcoats that claim they are compatible with epoxy? Aside from Barry Carroll of course...

 

Paul Koch

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HCMC Vietnam
soma said:
Infusion is super heavy. It's cheap and fast. But it ain't light.
Really depends what you are building and how ! We build nice light hulls using infusion but the secret is you MUST thermoform the plain foam and not have cuts or score marks in it that suck up the resin . It also must fit well and you need a perfect vacume or forget it !

Especially building carbon boats , it is either prepreg or infusion if you want a good result . Having said that infusion will be heavier than a prepreg boat but the cost should be substantially lower . We use a lot of prepreg cured in our autoclave in all heavilly loaded parts !

 

Zonker

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10 Ton boat should take ~2X the labor of a 5 Ton boat
Well don't forget that you also to have consider the building materials & method too. An all carbon, nomex boat will be much lighter than a glass one of similar size but labor hours would be similar. Ian's chart was for people building his style of boats (one-off glass/male molds)

 

Paul Koch

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Does anybody have any positive experience with the gelcoats that claim they are compatible with epoxy? Aside from Barry Carroll of course...
Most of our boats are infused Vinylester and we always put a vinyester skin coat against the gelcoat . BUT we only use epoxy prepreg and a lot of post taping reiforcing is done with epoxy with no issues . 

 

Zonker

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Could you create a legal structure where an LLC or Corp entity could own the work in progress including the hull, purchased parts etc
Don't even need to go that way. You can structure a contract that title to the work in progress is not held by the builder, but by the owner as progress payments are made. Normally the builder owns the boat until completion.

 

Zonker

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Most of our boats are infused Vinylester and we always put a vinyester skin coat against the gelcoat .
I understand this

BUT we only use epoxy prepreg and a lot of post taping reiforcing is done with epoxy with no issues . 
This I don't understand. I can understand post taping reinforcing INSIDE a vinyl laminate where there is an exterior gelcoat layer - but then you say you use epoxy pre-preg laminates when you say you're infusing Vinylester.

Maybe you're saying you do vinylester OR epoxy pre-preg? And gelcoat only on the vinylester boats?

 

Paul Koch

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I understand this

This I don't understand. I can understand post taping reinforcing INSIDE a vinyl laminate where there is an exterior gelcoat layer - but then you say you use epoxy pre-preg laminates when you say you're infusing Vinylester.

Maybe you're saying you do vinylester OR epoxy pre-preg? And gelcoat only on the vinylester boats?
Yes , we use Vinylester for the hulls behind gelcoats . But some parts are are taped in with epoxy . For instance epoxy prepreg chainplate bulkheads, that are made in our Autoclave are taped in to hulls made with Vinylester, using epoxy resin ! Daggerboard cases , made with epoxy prepreg , are taped in and reinforced with epoxy ! Rapido Trimarans are complex pieces of equipment and require lots of careful boat building to build ! Hence the price , you do get what you pay for ! As for hours quoted by some guys on here , they are living in fantasy land and no wonder some of them go broke building boats ! Costs , volumes , labor hours rise expotentially as a multihull gets longer !

 

harryproa

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2:1!? By volume or weight?   Carbon or glass?

Most carbon race boats shoot for 35 +/- 1% resin by weight in a prepreg laminate.  Are you suggesting that 15% more resin by weight in a carbon laminate is acceptable for a performance boat?  Perhaps I am misunderstanding your statement.  
Cored glass, by weight.  ie, the weight of the finished laminate, minus the dry weight of the core.       2:1 fibre:resin is 66.6:33.3     35% resin is 65:35.  

Does the 35% include the core wetout and bedding or is it just the ratio of the resin in the prepreg?    

Prepreg wets the fibres out with a bath and roller, then freezes it, thaws it, places it on the boat, heats it and vacuums it.  Any air (and moisture from condensation as it thaws) has to be sucked out through the resin and carbon when the resin is liquid and before it cures. Or each layer has to be vac bagged to remove the air.     Tedious and expensive.    

Infusion sucks all the air and moisture out, then replaces it with resin. 

If the infused laminate is the same as the prepreg (non stiched uni, knitted or woven), the resin and air contents should be equal to or lower than prepreg as exactly the correct amount of resin required goes into the infused laminate.  

I can't think of any component on a boat that would be better built from prepreg instead of infusion on a cost, time, performance or weight basis.  Marketing? Maybe, if your clients are gullible and fall for the aerospace guff.  

Zonker,

A while ago, we used the Hawkeye product on some 37' cats.  Worked great on samples, but after a couple of months, chunks of the gel coat fell off the boat.  Possibly a differential expansion problem, a styrene reaction or post cure shrinkage.   Perhaps be cautious if you are recommending it.  We used it because  it was pre infusion and the laminate was vac bagged.  Long gel time (3 days at room temp) epoxy was available and long gel time Ve/poly was not.  If you are using gel coat and infusing, I can't see any reason for using epoxy.     

Pretty sure the Gougeons had the same problem with the G32's, although not sure of the product. 

Ballotta in Peru spray gel coat onto Ve post infusion.  Can be thinner than in a mould, the mould surface does not have to be shiny and it is cheaper than paint.  http://harryproa.com/?p=488   Apparently been doing it for years, no problem.  

Paul,

If your prepreg parts are lighter than the infused ones, maybe check the infusion process.    

Autoclaved dagger cases epoxy bonded to vinylester is an interesting mix of materials and processes.   What is the reasoning behind it?

I'd be interested to hear the Rapido philosophy on daggerboards, rudders and propellors in high speed collisions with floating objects.    

Maybe Soma could tell us what he is doing on the 55 dagger cases, props and rudders as well?  

Multihull costs, etc only "rise exponentially" if the boats get wider and heavier and need bigger rigs and motors as well as getting longer.  If you only extend the length the cost increase is less than linear and makes a big improvement to speed and seakeeping.     The weight can actually be decreased if the added length is lowered and narrowed to give the same pitch dampening.   ie less buoyancy, but further from the centre of the boat.  

 

Zonker

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If your prepreg parts are lighter than the infused ones, maybe check the infusion process.
My 2nd hand experience with infusion is that it tends to be heavier because the resin will fill all those little gaps in the foam, and the edges of foam where transitions to solid glass occur. Somehow all the very top builders still think pre-preg makes a lighter boat (F1 car/fighter jet/hypercar) - because you never start with excess resin anywhere.

 


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