EVA foam and fiberglass. How would you do it?

So I have a very large wing that I made out of 1/4" EVA foam. Like many others I bought the kind that is like a work out mat. So one side is smooth and the other has the bumps



Of course I made the outside of the wing, the smooth side, but I want to reinforce the inside with fiberglass cloth and resin. But when I think about it, since the inside has the bumps like in the picture, the cloth wont be able to lay flat and will have lots of pockets right? Which I would guess, isnt a good thing.

I was thinking rondo, but it will make it so heavy and since its so large, it can possibly crack.

How would you go about reinforcing it, while still keeping it light?

Hmmm well, you do have quite a predicament.

I have found applying a layer of masking tape then doing fiber glass is the best way to go.

The masking tape soaks up some of the resin and applies to the foam.

BUT before you do this I would recommend getting some Elmers spray adhesive and doing a clean setup of your matting.

Who knows, spray adhesive and fiberglass may be just enough to get the result you want.

You can always go back and sand down some of the impressions you get if you are worried about weight and smoothness.

Tank

If you really want to go with the fiberglass cloth you could always use a roller to work the air bubbles. They have helped me in the past while building custom speaker boxes.

Are you set on doing fiberglass only? If you're looking to strengthen it and aren't determined to fiberglass, I'd suggest using Epsilon. I had a thread about it used to coat the "right" side of the foam but it would work just as well underneath.

ShermanTank said:

Hmmm well, you do have quite a predicament.

I have found applying a layer of masking tape then doing fiber glass is the best way to go.

The masking tape soaks up some of the resin and applies to the foam.

BUT before you do this I would recommend getting some Elmers spray adhesive and doing a clean setup of your matting.

Who knows, spray adhesive and fiberglass may be just enough to get the result you want.

You can always go back and sand down some of the impressions you get if you are worried about weight and smoothness.

Tank

Click to expand...

I may try that, I will do a test on scrap pieces to see how it works out.

If you really want to go with the fiberglass cloth you could always use a roller to work the air bubbles. They have helped me in the past while building custom speaker boxes.

Click to expand...

Oh thank I will try use that in my tests pieces

Are you set on doing fiberglass only? If you're looking to strengthen it and aren't determined to fiberglass, I'd suggest using Epsilon. I had a thread about it used to coat the "right" side of the foam but it would work just as well underneath.

Click to expand...

Yeah Im pretty set on using fiberglass since i can get it locally here in Hawaii.