SuperHawk Forum - composites. questions and tips. not for kids.

So you want to fiber eh? Well. Have I got some info that isn't pure bull

Poly the good: polyester resin chooches easier. Gardner to resin isn't so exact. If you go under usually it will firm up at lost strwgnth but not by more than 15%.
Poly is cheap. Poly sands easy. Poly is also available most anywhere. Here it is sold as the brand frp. (Japan)

Vinyl ester. I person ally hate it. Wrong ratio and it WO t kick at all. Too much and your working g window will close fatlster than a his legs when you say you only have a 20.
Vinylester is great for fuel tanks. It has high Chem resistance. It bonds like shit to carbonfiber but great to fiberglass. Also it don't mush as easily as poly. Wet poly and glass get gummy. It is death of a boat. I know well... Not easily available and it sets up in the can within three months if it has activator in it. Do not ass actoivator to mekp or it'll burn. Activators are cobalt and some other. If your resin is colored it probably has activator.

Epoxy. What a broad term. This is useless to talk about. Said to be the strong best but there are many epoxies some clear some shit brown. It all depends. Contact the supplier for a data sheet and find out what bercol and Rockwell hardness along with strength mean before purchase. You don't want dimalond hard glass brittle parts on a bike. Or stuff that melts.... I had a test piece turn to hot goo around my muffler.

Straits.

Here's two oddballs. If your not looking for strength just use woll or felt. I've even bonded old socks to body kits to fill a monster gap. Dont listen to old wives tales. People used to led in cars before filler and many sub enclosures and speaker boxes on show cars are either cotton will or felt. But it is heavy and as strong as a wet noodle.

Our most common buddy. Chop strand glass matt. Aka Mr itchy mess. Want a cheap faring for a race bike you know your gonna smash. One or two sheets of this costs less than a big Mac when bought in bulk and will explode on impact with the pavement but the fibERS will keep it remotely intact. Chop strand is pretty light and bends easy sands like a dream compared to carbon. Its great for non structural parts. Its also good for mold making because it flexes.

Glass weeve. Want a nice part that is much stronger and lighter switch from chop to weeve. This stuff usually rips but stops the spread as much as possible. Also semi structural parts can be made from this. A backside support that keeps your rear end suspended off the frame. But I wouldn't advise glass only to keep you off the tire..
It bonds good cuts good and forms easy but not as easy as chop around complex bends.

Carbonfiber. Contrary to internet bull. You can totally use cutoffs and don't wory about that crease it'll come out. People say buy rolls because they believe it or are paid to say it. Just remember square cuts are just cutoffs. Dont expect The best. You don't need a vaccum setup but it makes life easy. Fiber don't form for shit when wet its stiffer thantutenkamens corpse. It bends like paper and goes back like paper. Ever try to jam paper around a complex bend without relief cuts? It also falls apart. Easy tip is to use some wet resin to glue the fibers together and to the mold. Stuff needs a weight or bag or something it don't stay still like glass. It tends to lift. Also it sands like shit so be warned.

Third world sweat shop tip. Clear tape is an exelent surface it'll leave a line but if you got a small ding in your mold tape it up and try it out sticky side mold side.

My question is on chooching. My vinylester is taking wayyy more than 1% and its kept inside. Also it isn't old. Like 3% mekp!!