best epoxy filler/reinforcement?

hey guys
what filler do you recommend that is high strength?? i cant find cab-o-sil in NZ but what about silica sand?? or what else do you recommend??


thanks for your time
matt

The other name for Cabosil is "fumed silica".

There is no magic bullet. For layup joints, it's basically raw epoxy unless you want to make sure it doesn't "run", then you use a little fumed silica (Cabosil). For filets, if you want sandabile, use microballons, if doing a filet, use cabosil (or the other names), or the best (strongest) is to use "milled fabric" Normally, it's "cotton" and very fine. The other approach is to use fiberglass fibers. Either of the later is extremely hard to sand, so you only use in places where you don't.

For more information, check out www.westsystems.com or system3 or any of the good epoxy houses. They will have descriptions of what kind of fillers.

I'd be surprised if you can't get it in NZ. Find a good boat repair place that does Fiberglass repair. They'll for sure have some.

Alan

IIRC Cab-o-sil and micro-ballons are used to thicken epoxy without adding any weight to the mixture. they do NOT add any strength. You can also use wood flour to thicken epoxy.

Silica sand might thicken the mixture, but I imagine it would weigh a ton. The only way to add strength is to add glass fibers. Milled or chopped fiberglas cloth.

There is also good information at www.raka.com

what filler do you recommend that is high strength??

Click to expand...

No filler =high strength

but any epoxy joint(with or without filler)should be plenty strong
Construction technique is every bit as important..if not more