Cape Horn Boats Concern

[jiggerpro]

Being in the market looking for a nice and beautiful 31 cc, I came across Cape Horn Boats which I found particularly attractive but reading their construction methods I was surprised with their claim of making the lamination of the hull layer by layer and thus making secondary bonds between layers of fiberglass, surprised by this I emailed them and asked and this is what I got as an answer:

To answer some of your concerns, the laminate layers are allowed to completely cure to reduce shrinkage and distortion in the hull shape by not building up excess heat from multiple layers. The laminate exotherm window for our polyester resin is 24 hrs. We still grind or scuff the surface to allow more bonds to form on the molecular level. This ensures a secondary bond is formed and actually superior to multiple layers at one time.

Tyler Cesar
Cape Horn Boats
850-626-2211

SHOULD I BELIEVE THEY GRIND AND SCUFF THE VAST AND LARGE SURFACES OF A HULL LAMINATE TO GET JUST A SECONDARY BOND OR IS THIS CLAIM AN INSULT TO THE INTELLIGENCE

[jiggerpro]

So they claim they grind and scuff the surface of every laminate layer, If we were to believe they do such an umbelivably unnecessary grinding and scuffing work ..... what would be the point on doing so ?? .......... do they do it just to get a secondary interlaminar bond which for sure is a poorer bond than a primary one in which the laminate is actually a one piece laminate without any secondary bonds ??? , its either they are big liars or stupid for working for nothing.

I hope that I made my assumptions wrongly and that someone can throw some light about this, otherwise I will be forced to believe there are some very large liars working at Capehorn Boats and liars should not be trusted for the construction of a boat.

Despite this, I believe theirs are beautifully designed boats but about their building methods ... I have many doubts, the same opinion I have about thir credibility after knowing about what they say about construction of their hulls

[Manie B]

Absolute madness - they are crazy - Jiggerpro is correct.

[Roly]

to allow more bonds to form on the molecular level.

Wow.....weird. Bollocks, imo.
Do you not get a limited chemical bond anyway, with unwaxed resin within a 48 hr window, diminishing thereafter?
(Air retardion of the top molecular layers)

Secondary bond.
Scuff?? At least they should use 40 grit with a vengeance,or peelply.

And sanding unwaxed resin is like trying to please your mother-in-law. "Scuffing" waxed resin is inviting a disaster.
I would not be happy with his response. Although, it may not be indicative of what is going on in the factory;He just ain't good at explaining.

Its this kind of shite that scares me about polyester and workers with no passion for reality.

[tinhorn]

Not sure I see the problem with this technique. If you lay up a large, thick part, the heat produced as it cures can be extreme. I've seen this lead to partial demolding, creating a deformed surface in the finished product. It's quite common to lay up one "skin" layer to cure before the rest of the layup continues in order to reduce "print-through" - the pattern of the woven roving showing up in the finished product.

I don't believe they'd need to grind and/or sand each square inch. In fact, doing so would eliminate the tacky surface we like to see for subsequent layers. I'm guessing they grind the edges of overlaps, and sand off any tiny spears of glass that may be sticking up in order to eliminate bubles between the layers. Yup, I've often seen a crew spending considerable time hand-sanding a large part for just this reason.

I've used this same process in building car bodies, as well as hundreds of large industrial products, and am not aware of any delaminations as a result of using this process.

[Guillermo]

I'm with you, tinhorn, we used the same technique when I worked for Rodman, to avoid heat building and print through; and for sure we didn't eliminate the tacking needed for the proper bonding of the next layer . Probably Cape Horn's explanations are somewhat confusing, but I think the general idea is clear. I've sent a message to them, bringing their attention to this thread. I hope (and wish) they'll reply soon.

Cheers.

[FAST FRED]

"I don't believe they'd need to grind and/or sand each square inch."

If it is true secondary bond, THEY HAD BETTER!

The USCG requires 85% clean glass showing for every and any secondary bonds.

My guess would be they toss the next few layers on before the primary bond window closes.

FF

[jiggerpro]

Hello Guillermo, I am a Spanish (living in the Canaries) citizen like you only writing to you in english for politness with the rest of the forum and had plans on contacting you looking for some help on the development of something I have in mind after you was reccommended to me by someone else in the forum. About contacting via e-mail with the "cape horn people", is not so easy since there seems to be some kind of incompatibility problem between Telefonica and their e-mail I contacted them trough one of their dealers in Texas.

[Guillermo]

Hi, jiggerpro.
Writing in english in these forums is not only a matter of politeness, but of the rules here: communication language is english.
I will gladly help you if I can to develope your ideas.
By the way: I urgently need to contact the other Canary member of these forums (he lives in Tenerife) who is very good in working with 3D. I don't remember his nick and I have lost his contacts. By any chance do you know him? Please PM me if so.

Cheers.