Fibreglass/foam/plywood box

Hi guys

I am restoring a camper box for a unimog truck and I thought this place would be best to ask for advice as it uses a lot of the same materials as many boats.

The plywood on the inside that is stuck to the foam is pretty much fused together and I found it very difficult to ply off without damaging the foam.

The plywood is pretty thin - 3mm or something.

So I resorted to using an angle grinder with a sandpaper disc and a belt sander.

The wood is covered in mould and is pretty rotten in places, it kicks up a horrific stink when sanding - kind of sweet fungi kinda smell.

My question is - is this a wise way to proceed in removing the plywood? I am using a mask and a shop vac to keep the dust exposure to a minimum; but the smell does kinda make me worry i'm breathing in something kinda nasty from the glues or something.

Any thoughts?

 

Here is a photo

 

So what is this ply, the inner lining of the van, and the foam is insulation ? Why do you need to remove the lining, if it is stuck down well ?

 

Yes it’s a kind of softwood plywood. It is quite rotten and full of mold. I would rather remove it completely so there is no source of mold.

 

I have done it.

oscillating tool is the only way my friend...

best of luck; it isn't much fun, the oscillating tool with a carbide blade can lay flat and glide along the glass

a chisel can gouge the glass

The wood is 1/8" luan.

 

The black mold can get into your lungs and cause trouble. Smelling it is bad. Run a fan across the work.

 

Glass?

 

Mine was fiberglass exterior with a luan core.

 

Yours is luan and foam? Are you just on the interior?

I'd still use an oscillating tool.

lots of control over depth and angles of cut

 

Ahh I see. Yes it is the same except with foam between. Thanks for the suggestion, I will see if I can borrow an oscillating tool. I was using a grinder but this is quite time extensive.

I’m mainly worried about poisoning myself from the glues in the Luan.

 

Just rip the plywood off with a crowbar, and do not worry about the foam. You will have to remove the foam anyway, it is full of mold spores and rot bacteria. When you get to clean metal (or whatever the exterior is made ot of) you clean it with a sander and glue in new foam.

 

It is a polyurethane foam (styrofoam) that is bonded to the exterior fibreglass. It essentially makes up the whole structure as it is a composite construction. This would be impossible. The foam is fine underneath and is not permeable.

 

Of course it is possible. Just cut the foam out and reglue new foam in with epoxy.

 

Easy to say, more difficult to do, applies to many things in life. I would leave the foam alone, other than when you have removed the rotten lining, ensure it is dry, before re-lining. You may need to install a strong fan to blow air through the box, to dry it, I doubt it will dry out too readily over there in Old Blighty, even though summer is coming !

 

I’d cut the plywood into thin strips with a circular saw, set the blade to just the thickness of the wood.
This should make it easier to peel off with the multi tool.
There are scraper blades available for that, as well as for reciprocating saws.
Treat the foam for mold/mildew and dry it out well before applying new plywood.