Fiberglass + Foam: A Tutorial and Discussion

[willsonman]

You can but I'd not recommend it unless you are using a glue that is much more permanent than hot glue. White gorilla glue would be my recommendation. You'll want to also remove all the paper. So then if you do that, then you may as well have saved yourself the hassle of the odd pieces and just glassed the flat pieces before you assemble them.

 

[HilldaFlyer]

Question, can you glass a ft model after the build?

Same answer as Josh. I've done it several times. There are pluses and minuses to both ways, glassing before and after.

After built, it is hard to get the fiberglass mesh to lay into and around hard corners, but it is doable by "working" the cloth as the resin stiffens. Gluing the model together after glassing also has a downside of making sure the glue adheres to the glassed surface where the parts join, so roughen it up a bit before gluing. Glassing after the model is built holds the parts together permanently. If something is askew, it will be that way for the life of the model.

My go-to method is to peel the paper off both sides of the flat foam sheet, glass the entire sheet (both sides) and then cut the parts out. You can really get the resin thin and light with this method.

I have, however, glassed over the paper on an already built model. The downside to this is the fiberglass is only adhered with the strength of the paper/foam interface. The paper will peel off of the foam while the fiberglass will never disassociate from the paper.

Good luck!

 

[Sly Fox]

You can but I'd not recommend it unless you are using a glue that is much more permanent than hot glue. White gorilla glue would be my recommendation. You'll want to also remove all the paper. So then if you do that, then you may as well have saved yourself the hassle of the odd pieces and just glassed the flat pieces before you assemble them.

That would only work for models that don't require shapping/curving though right?

 

[willsonman]

Sort of. Again, it depends on the model and what more you need to do. I've built foam models with GG where sheets of foam are applied as panels and you can still sand/blend the seams. Still, this was before applying glass. So, strategically pick your method(s).