Folding FRP

[joshuag]

Hello!

I don't want to buy a 4x8 sheet of FRP just to test this so I thought I would ask. Has anyone tried folding FRP by making a 45 degree plunge cut along the crease, heating it, and then folding it 90 degrees?

Even if this works the seam would probably tear right during normal use, right?

Thanks!

[saltydawg]

It might work with the home depot stuff, but anything with actual glass in it I doubt it. I will go grab a scrap piece of actual fiberglass with gel coat and try heating it to see what happens. Give me a few mins

Edit that was a big nope. I got it very warm basically hot to the touch. As soon as it bent the gel coat cracked, infact it cracked when normally it would have flexed. I think the resin did soften so much instead of bending it tried to fold which put more stress on the gel coat. As I said I dont know that the home depot stuff has real gel coat on it or even much glass. I do know when you cut it smells like polyester resin thou.

[joshuag]

That was so fast. Thanks for doing that saltydawg!

Did you cut along the crease first before heating? I was wondering if removing material along the crease / hinge would make it work. Like how a plastic living hinge is notched out on the sides.

Sounds like the gel coat would crack regardless from what you said though.

Thanks!

It might work with the home depot stuff, but anything with actual glass in it I doubt it. I will go grab a scrap piece of actual fiberglass with gel coat and try heating it to see what happens. Give me a few mins

Edit that was a big nope. I got it very warm basically hot to the touch. As soon as it bent the gel coat cracked, infact it cracked when normally it would have flexed. I think the resin did soften so much instead of bending it tried to fold which put more stress on the gel coat. As I said I dont know that the home depot stuff has real gel coat on it or even much glass. I do know when you cut it smells like polyester resin thou.

[saltydawg]

Sounds like the gel coat would crack regardless from what you said though.

Yup thats where I was going with it. I did not cut out any of the back, the gel coat was just way to brittle even warm/hot.

Send me your address and I will mail you a piece that fits in an envelope.

if anyone wants scrap and lives close I have 4 pieces 10 to 14 long by 2.5 wide they could have just for showing up.

I live in maryland

[joshuag]

Looks like it's back to PMF for me. Thanks again!

Sounds like the gel coat would crack regardless from what you said though.

Yup thats where I was going with it. I did not cut out any of the back, the gel coat was just way to brittle even warm/hot.

Send me your address and I will mail you a piece that fits in an envelope.

if anyone wants scrap and lives close I have 4 pieces 10 to 14 long by 2.5 wide they could have just for showing up.

I live in maryland

[saltydawg]

PMF for me would be my third option. First would be fiber glass skin with the corners glassed in, next would be fiberglass third would be PMF.

But I would not use a single piece of wood in it except removable stuff, nothing structural or skin which would put PMF a distant third. After seeing the video on the brudder trailers I thought about going over grown foamy completely glassed inside and out. There are some easy ways to do glass and not need to fill the weave near as much, like simple plastic drop cloth. Epoxy wont stick to it, so just brushing a final layer of epoxy and putting on plastic sheet and smoothing it out will fill 95% of the weave. Or just simply micro ballons mixed with epoxy and sanded off then/or lots of primer to fill. You put enough micro ballons in epoxy and you could sand a 1/2 bump off by hand in 30 seconds.

[joshuag]

I'm limited to what I can build in my apartment

[saltydawg]

I'm limited to what I can build in my apartment

if your not in a large city, go rent a 10x20 storage space for a few months. Find one that is 1 dollar to move in and rent it for 3 months, its an excuse to buy a inverter generator for power to work with