You’ll need a polishing compound. That pretty much goes for everything that you have to sand down.
thought so, just wanst sure… what do you recommend? otherwise i’d just pick up something from the local auto store…
I use the 3M stuff from a local auto body supply store. You can find it online but it’s not any cheaper than what you can get locally.
question:
After you lay up a part in c.f and its cures and all, can you spray the back of it with flat back spray paint to cover up any daylight holes that might be showing thru the weave? on my test peice i laied 2 layers and there were only like 2 spots that still had light comming thru. so i wondered if i didn spray it would it be noticable at all? from the finished side
another question:
Now that i’ve moved on to the next part (the one i want to keep) should i pop it out of the mold being that its only one layer of 3k. or should i add the backing and all before i take it out? my only concern is i dont want to do all the extra work and waste materials if there are too many bad spots… what do you typically do.
Robby,
simple black spray paint will fix the problem. Most of the time it won’t show up depending on where the piece is going to be installed. If there’s no light behind it then you won’t see the gaps. As for your second question, it’s a tough call. If you remove the piece with just one layer, you’ll certainly end up with a cracked/over stressed piece. Just go through the whole process and if it comes out bad then it’s going to come out bad. Examine the piece and improve upon it the next time around. If you lay up just one layer and it turns out perfect, it’s still going to be useless because it’s cracked or broken. So pick your poison. I typically remove the finished piece and go from there. If it’s bad then I just trash the entire piece. I don’t dwell on it too much because it just stresses me out. Sometimes I save the scraps and do “stress tests” on them. Like smash them… jump on them… blow them up… shoot them… throw them at people… etc. 
lol yea i did one of those stress test with the test piece. too bad all the bb’s i was shootign at it came back at me…lol…
how many layers of c/f do you typically use per part, on non structual parts. mine is just an a-pillar so one layer would be strong enough. especiall after seing my buddies pillars he ordered from carbontrixs, they were thin, and all the pods were solid fiber glass the c/f stoped at the base of them…
I think you can get away with one layer of graphite cloth and one layer of 4-6oz fiberglass cloth backup.
cool, thats what my buddy and i were just talking about… since the roll of matt we got is cheap it wont be any loss really if the part is bad. but i dont think it will be… we worked it into place over like an hour (temp droped and the resin didnt gel up as quickly as i hoped)
And this time i made sure to leave slack on the fabric as i layed it so it would fit nicely in the bends. Should have some pics this next weekend. hopefully they will be proud ones…