Foam coring an old boat - insulation too

[Abrain]

I am redoing my old boats interior specifically the v-berth. She had the Styrofoam insulation between stringers with White oak slats running horizontal, it looked beautiful. Age has caught up to her and so the stringers, oak and foam were removed. Shes naked hull in the V-berth.

This is one idea I am considering.

I am thinking I would place 1" foam (type unknown at this moment) all over the bald curvy bulkheads without stringers. Simply glue them (although I have considered other means of attachment). Then epoxy fiberglass cloth over the foam to create a finish that can be painted.

Would you expect this to hold over the years? I am hesitating because its not a vintage look and I am unfamiliar with foam cored products.

[natew]

I am considering the same on the interior of my boat, solely for insulation purposes. I haven't decided on materials yet but am thinking that foam insulation board that they sell at home depot and the like.

Don't think I would to the expense of fiberglassing over it, also seems like that would be a lot of added weight. Might, at best, go over it all with a high build epoxy primer and then a finish coat.. Would think that if you place the pieces flush enough that the primer would be capable of filling in/over the gaps and uneven surfaces.

Don't know, would be curious to hear other ideas.

[Stumble]

Foam coring is a process indicative of structural design. Is this intended just for insulation, or for reinforcing the area?

[Zach]

Painted hull liners are tough, because the curves are not able to be developed out of sheet goods. To get a sheet rock grade finish, takes a lot of putty and sanding work. It is the reason why so many new boats come with a drop in hull liner, or have soft walls.

A hull liner built in with straight flat runs of plywood is the fastest... works, but doesn't look as good but it is fast, and easy to get painted. Work boat style... if you do have to repair it you have to cut it out of the way.

Soft walls, or wood ceiling strips look good... and are very fast to install in Comparison to a curved hull liner like you are talking about. Soft walls and wood Ceilings are in all new custom boats, because what you are about to undertake costs more in labor than doing soft walls or wood ceiling strips. Even the ridiculous leather-like padded vinyl proprietary stuff still costs less than doing what you want.

However, if you want it flat smooth and painted with the foam as a small amount of insulation you may be on the right track. Getting from here to there takes a fair bit of time.

You will need to learn how to vacuum bag the foam into place. I would use a polyester based product like polybond rather than epoxy, as you will save a year of your life in the sanding. Long Board sand the foam before fiberglassing it. From there, I'd put two layers of 1 1/2 ounce mat over the surface and let it kick... with polyester. Tough enough to take a bump, but no weave to grind through or show later. You can use peel ply if you like it, but you may be best off with 1-2 foot wide strips of it as a full panel doesn't stretch much.

Then sand it smooth with 80 grit. Take the shine off it by hand any of the low spots that may still exist. Wipe it down with solvent, then putty the surface with Adtech P77, or a high grade auto body filler.

From there you'll putty it once top to bottom with a screed spanning the lows. Sand it, then putty it once side to side and sand it. When it is all one color and evenly built out, you'll take a spray guide coat or dry guide coat and sand it with an orbital sander. Putty the pin holes, and then use awlgrip 545 primer as a sealer that will be a good base for most any topcoat you want to put on it. Household, and even automotive primer doesn't normally do the job over fiberglass without adhesion issues some time soon...

Then switch over to an oil base or latex house paint to keep it easy to clean and maintain.

Fair disclosure: This is the sort of stuff you do once, and try your best to talk anyone else out of doing it in the future. The entire panel is a low spot. Fairing the outside of the boat is one thing, because the board rides over it. Making a concave surface look good without lumps and bumps takes a bit more finesse....

Wood trim and joinery covers a heck of a lot of ground quickly. It looks fiddly, and you need a tools and work space... but a set of cabinets hung in place would save you a lot of itching.

Zach

[Abrain]

Natew,

Don't think I would to the expense of fiberglassing over it, also seems like that would be a lot of added weight. Might, at best, go over it all with a high build epoxy primer and then a finish coat.. Would think that if you place the pieces flush enough that the primer would be capable of filling in/over the gaps and uneven surfaces.

This is a great idea son the surface (pun intended ). I did not consider this thanks for the foresight. I still hesitate on the home depot foam as it may not be suited for marine environments, I read Lowes and Home Depot closed cell foam has voids to trap water vapor from air [book : this old boat]. Then again I just want insulation. Do you think banging the foam covered in epoxy build up would be strong enough? My 4 year old get rowdy at times lol. Sounds like it would work and save weight.

Stumble,

This is simply for insulating and I know foam core is mostly for structures but I had no other words to describe this.

[Abrain]

Zach,

Dam you deflated my aspirations quickly. Thanks I just hate to use more wood again.

[Cheechako]

I think you will find that just replacing the ceiling strips (slats as you call them) and putting new foam under (between the hull and the strips) will look a whole lot better, be easier and less messy. You could use anything from cedar to something more exotic.
Is something wrong with the oak slats? water stained?
Laying fiberglass and resin up there in the berth is going to be very messy, very lumpy when done etc. Then all the sanding and fiberglass dust everywhere will be a mess.... it's a lot of work and may never look good again.

[martinjrichter]

Your original question "Will it last". Foam surfboards are constructed in much the same way and last for years.

Sanding the stuff is a messy process but going back to surfboard constructiion, they use power planes to do much of the work and get a smooth surface before sanding. I would suggest a full face mask to protect your lungs and dust control.

[DeepFrz]

This is what I would recommend. The sheet stuff.
http://www.google.ca/url?sa=t&rct=j&...56343320,d.b2I

[JonathanSail]

In the v-berth of my Pearson 28-1 I was able to use bubble foil, blue foam and frp sheets (in that order) all from Lowe's to insulate the hull sides. It worked for my application because the sides were relatively flat/etc.. The benefits of this approach were that I only had to fit/cut and then assemble. I didn't glue, paint or do anything else messy. I didn't add any insulation to the ceiling/deck or below the bed platform though I did add ventilation below the mattress to help cut down on condensation.

In extreme environments I could take this further but the main goal was to stabilize the temps in the v-berth so that the single heater or AC in the main cabin were effective in the sleeping area as well. I initially did this work in the Summer heat and the difference was noticeable and the v-berth was slower to heat up after the sun hit the boat in the am. The AC was able to keep up so that I could sleep in if I wanted. This was done while I was still on the hard with the bow pointed South so while the before/after assessment wasn't scientific it was fairly accurate.

I also cut out panels from the bubble foil that fit into the portlight frames which make a big difference in cutting down on heat gain or loss (season depending) and also do a great job of blocking out all light if desired. etc.

There are a few photos from back when I did this here:

Poolio's sailing and travel blog. : Interior Improvements

Hope that helps provide a few more, relevant ideas,

Jonathan

[Cheechako]

Originally Posted by DeepFrz

This is what I would recommend. The sheet stuff.
http://www.google.ca/url?sa=t&rct=j&...56343320,d.b2I

Nice looking stuff... especially for ductwork. is it expensive?
So from an engineering standpoint.. is insulation to keep out/in heat different than insulation to keep cold out/in?

[Nicholson58]

We did structural repairs by using US Composites 635 THIN epoxy and microballoons. Epoxy :*Epoxy Resins and Hardeners You need your area to be filled to be enclosed. i.e. two skins seperated by hollow cavity. Our deck balsa core was wet. We drilled 2" holes (hole saw) and dug the wet core out. Glassed over the holes after extensive drying. Pumped a slurry of epoxy & balloons into the cavity using re-usable calking gun tubes (McMaster Carr). Filling a vertical cavity would be comparitively simple. The 635 resin is extremely slow cure with about 4 to 6 hours of working time and 3 days or more to full hard. The resultant syntactic foam is totally waterproof and very light. Also - very strong and a great structural enhancement. I would NEVER use urethane foam or balsa again.

PHOTOS:
holes cut & balsa core removed
use wood struts to hold new wet glass & release film up
struts & film removed. You can see through the new glass.
white syntactic mixture pumped in and cured.

[jgbrown]

Originally Posted by Cheechako

Nice looking stuff... especially for ductwork. is it expensive?
So from an engineering standpoint.. is insulation to keep out/in heat different than insulation to keep cold out/in?

Harder to get. I don't understand bubble wrap (less efficient, aluminized surface suited for other uses). Volara is close to armaflex etc and cheaper. I used it in roll form. Closed celled fit the hull nicely. Sound damping too.

[DeepFrz]

is insulation to keep out/in heat different than insulation to keep cold out/in?

Cold is an absence of heat, so no. There will be insulation with different properties, of course, depending on what is being insulated, the surface(s) to be insulated etc. The nice thing about Armaflex (Volara I know nothing about) is it will conform to the hull nicely, is easily cut, can be easily removed later if need be, does not grow things, and I believe it is hypoallergenic.

[Abrain]

deepFrz

How much is this stuff or better who sells it? I cant seem to find a provider.

JonathanSail

I have tried this bubble wrap stuff and it has not worked too well - by the way you need two layers of the bubble wrap if i recall correctly.