interior construction questions

[pressuredrop]

hey yall by name is Ben i am 22 and i am the proud new owner of a 1964 allied seawind 30... i have completely rebuilt 2 smaller boats, a rhodes 19 and 20' seacraft (power boat) so i have a very good idea of what i am getting myself into

this is my new boat:
http://www.alliedseawindii.org/boats/SWI-025/SWI-025.html
all of those pictures are about 4 years old, but not much has changed, just hasnt been used a whole lot in that time, but the engine runs and the radar works and the rigging and deck and whole boat is structurally sound, just needs some good lovin. i picked it up for a song so i figure i cant loose. i plan i having the engine rebuilt, complete rewire and spruce up the interior amoung other things end hopefully be living on it by the end of the summer.


now with my experience on small fiberglass boats i know all the wood needs to be completely encapsulated in glass. i sense that that is not the case for sailboat interiors, so my question is what is the best wood to use for non structural interior peices, pieces that will be seen will be covered in vaneer of some kind. ply?.... if so what kind, and what needs to be done to the wood, epoxy coat of some kind?, or just throw it in and keep it dry?

this is the first of many questions but i look forward the wealth of knowledge you all have to share.
and if anyone knows any history on this boat id love to hear about it.

till next tide,
Ben

[Maren]

Originally Posted by pressuredrop

... , so my question is what is the best wood to use for non structural interior peices, pieces that will be seen will be covered in vaneer of some kind. ply?.... if so what kind, and what needs to be done to the wood, epoxy coat of some kind?, or just throw it in and keep it dry?

For non-structural pieces, the materials used have more to do with the cost to appearance curve than to performance. The sweet spot is often concluded as some sort of ply, coated in epoxy and skinned in veneer. You are on the right track by avoiding MDF.

Now the fur flies. The ply used isn't of all that much importance assuming you are willing to take the risk at the time of sale. Put differently:

You could use exterior grade ply, fill the void with thickened epoxy, coat and skin. The amount of work is high, the epoxy is expensive and heavy and the resultant product still runs the risk of being look the prospective buyer thinking: "oh god, I wonder what other corners have been cut?" The problem here is getting a fair surface to work with. Laminate shows, or rather transmits, flaws easily. What you can't see, you feel.

You could use marine ply, coat and skin and be done with it. The cost of the wood is high but there are no voids.

You could use interior grade or finish grade ply with the similar results.

The key point is the wood rarely gets wet. If you are quite certain of this, you need the epoxy. You should also keep in mind finishing techniques (eg edge veneers or, better yet, molding to act as a fiddle, stiffen the piece and give an appearance of thickness).

Since you are on this track though, I would also suggest you also look at foam.

Hope that helps. Oh, and that looks to have been a really good buy.

[GordMay]

See Chapter 3 - Materials
for good information on boatbuilding woods etc:

USCG Guidance on Inspection, Repair, and Maintenance of Wooden Hulls
NVIC 7-95
http://www.uscg.mil/hq/cg5/nvic/pdf/1995/n7-95.pdf

[SkiprJohn]

Aloha Ben,

If it were me (I'm doing nearly the same thing with redo of interior) I would used 1/4" or 1/2" (depending on where) marine ply with a high quality exterior oil based paint or a two part epoxy paint for furniture that is not counter tops. I would use marine ply with a laminate for countertops.

Two books that I'd recommend are "This Old Boat" and "From a Bare Hull." Most public libraries will have them and I'd look through them before buying.

An acquaintance of mine sailed a Seawind round the world. His was a ketch without a pilothouse. My wife and I went sailing with him once before he took off and I was really impressed with the way the boat handled.

Good luck with your project.

Kind regards,
JohnL

[Boracay]

I've mostly used pine "Ecoply" (A New Zealand product, "A" bond, C/D faces). Cheap, light and easy to cut and work with basic tools.

12mm if it gets walked, leaned or stored on, 7mm otherwise.

Some photos in my blog.

I prime/protect the surfaces and edges by painting with 5:1 generic epoxy thinned 15-20% (soaks right in). If the surface is going to see hard wear I repeat the priming. If there are voids that I can't cut/work round I fill them with thickened (cotton fibres) epoxy resin.

I sand lightly and then topcoat with single pack exterior grade polyurethane (2-3 coats depending on where and wear). White or clear.

Seems to hold up pretty well.

I tried 2 pack polyurethane but it wasn't worth the result (to my taste) or the risks with the isocyanate.