fiberglass mat fins

would 1/4 thick sheet made from fiberglass mat work to make fins out of?

Hey Deathfrog

It would work but chopped strand mat (I assume that is what you mean) tends to be quite a bit more “resin-rich” when laid up and will not have anywhere near the flex that cloth has. All those fibres going everywhichway look pretty ugly too. I’ve done it a couple of time in the dark distant past and you can make fins OK out of it. Maybe a plywood laminate would be a lighter option. Quarter inch seem a little thin but if that’s all you’ve got then go do it.

well I just don’t think that I would have the paitence to do layered ones, its hard for me to foil wooden fins without getting bored. I made some recently, but I don’t think I will again anytime soon. Why I say 1/4 inch is because thats the size for FCS plugs and I tend to have a hard time thinning out the plugs to the right thickness. I was also wondering, if a homeade FCS is slightly wobbly in the plugs, will it rip them out?

Ahh, I get the drift now. Should be OK to do that. The fins shouldn’t be a problem in the box and as long as the grub screw is tight you won’t get much movement. Those FCS plugs bond in pretty good and a loose fin should not cause any worries.

I’ve used mat.

I’ll never use mat again.

I would encourage you to take my errors as your learning experience.

It takes less than an hour to do a small plate (12"x12") layup.

yeah, I found foiling and sanding chopped mat fins I made MUCH more time-consuming and a hassle than laying up layers of 4 or 6 oz cloth.

The chopped mat ones looked really strange [‘texture-wise’]. I also had a bugger of a time trying to get even foils… much easier and quicker with ply core. Or laying up 4 or 6oz cloth .

just my experience…


No patience, bored, your getting in the wrong line of work. Building surfboards requires mucho patience, otherwise you’ll wind up with, junk in, junk out

yea, I know. I wasn’t really bored, it was just kinda near the end of the foiling process wehre I was trying to get everything even and it didn’t look like I was making much progress. And I had to pee. It was fun though, but I doubt I will do a thruster set until I have to, I Just did a few center fins.