CSC 30 Catamaran- the coastal passage

I'm not sure I understand the implication ? I was just referring to the cost of the panels. Ply would just require a big scarf joint and one layer of 4oz cloth to be comparable to a foam core

so whats the foam core panel cost per 32 sq ft panel ?

 

Foam core can be laid up full length, complete, on a table with gelcoat the lot, rebates built in for panel joins. so minimal finishing compared to ply. Some people prefer fibreglass to timber, just check out your local marina !
I am not suggesting it is cheaper than ply I only highlighted the fact that one could use glass panels if that was your preferred material.
The point being that there is a lot more labour and materials beyond the cheap ply.
RR

 

$50 bucks for BS 1088 is a pretty good price for a pretty good material. I'm not saying go with CDX. Or am I just misunderstanding you. From what I can gather a cat build under say 50' is structurally 6 one way a half dozen the other using foam core or ply in terms of efficiency so if the ply is cheaper, why not, specially if its your own labor and half the fun is in the building. That and there's a lot less noxious chemicals involved \\

I suppose I just prefer a more natural building material.

 

I prefer wood too ! But if you wanted too build in glass you could quite easily, indeed you may not even need foam, a core mat panel would work too, if you prefer glass ! ( or are sensitive to epoxy) lol
RR

 

Standard 4x8 panel of foam? $247.

 

yah thats huge, on a cat of this size I'd just go ply and a layer of glass. That and peanut based epoxy. Couple of cheap 10 hp diesels converted to alternative fuels and a hippie chick to keep me company.

 

And a little green bag !

 

Silly as it seams I dont' smoke. But I am dying to spend a summer lazing around on the water somewhere while I put in my time for my captains license. I suppose I could do the inside passage on a small light cat. And then come home and build something I could actually do tours on. Who knows, I'm just pondering my options when I came across this thread with the groovy easy hull form. Pretty sure even that hippie chick could build that thing.

 

Nothing silly about not smoking ! The build method is straight from Crowthers Buccaneer 24, I'm sure he did it independently, he seems that kinda guy.
RR

 

It just looked to easy to ignore. And ply is a material I'm painfully familiar with.

 

Boston, you should at least run the numbers on a grp flat panel build, you may be surprised, the cost can be quite reasonable if you use the "appropriate technology" approach. If you build a full length layup table, gelcoat, iso polyester resin or vinylester, instead of epoxy and balsa core instead of foam.You also need to be honest about the cost of a ply build as its not just plywood, its epoxy and supplies,glass cloth,epoxy primers, paint etc and a whole lot more work to arrive at a finished hull of comparable standard of finish.
Steve.

 

Also used for generations of Sharpies and Bill Kristophersons 24' cat and tri.

 

Ya, Redreuben

Simplicity is the key Better/More materials seems to be the answer!

Here is a very interesting build site using pannel construction
Foam pannel would work well with this construction technique.

http://buildacatamaran.com/bblog.html

ALOHA

 

Feel sorry for the guy, getting conned into using balsa core.

I've worked on delamination and water absorption issues with too many balsa cored boats to recommend it as a core.

Outgassing seems to be an issue which professional cored construction boat builders are well aware of. And the core manufacturers prefer to ignore.

Generally with any type of core, except for ply, preheating over time before laminating, at a cooler temperature, is good practice.

And. as suggested, coating while the substrate is cooling.

Gudgeons book has recommendations for several coats to fill pinholes due to outgassing from coatings.

Another option when coating is to use a heat gun or gas torch to warm the surface enough to release trapped gas.

 

I admit to being biased towards ply. Or ply/foam for light weight flat panels, having had a boat built from that for 35 years.

We wooded part of the boat for the first time, while rebuilding, after 30 years to find the ply, epoxy and foam were still like new underneath the epoxy coating.

In contrast to many balsa cored boats that were a soggy mess. Even ones by good builders.

Getting a finely finished fair hull is a lot easier with ply and 8 oz glass than with any other form of construction.