Nice polished look on Carbon Fiber?

General Composites Discussions Composites Talk
#1

How does everyone do it?

I put my flat products on mirrored stainless steel. Comes out decent, but I like to atleast put a protective coat of resin on it…is that suggested because afterwards I get extremely tiny bubbles even though I put a heat gun over it? Is there even a point on doing this? I really would like to use clear coat, but solvents get used to clean the product I make so the clear coat will come right off!

I would just like to know everyones methods and if a small coat of epoxy resin is even necessary.

…another note maybe explain how you guys use sand paper to get a gloss look after applying a resin coat. Thanks.

#2

Start with 400 grit and flat it down, then work your way through the grits 600-800-1200-2000 and then use a polishing compound.

Just need to be careful to not rub through the epoxy.

#3

Coat your mold with 2K polyurethane clear before infusing.

#4

If you guys need ready made carbon fiber sheets in matte/gloss finish then contact me…

#5

Could I apply the polyurethane afterwards when product has cured? The problem I have with resin is it does not stay even and starts to dry out the way water does when its drying. Also I have a ton of swirl marks in my resin if I apply too thick. Is the Polyurethane the same and will it also be permanent and not come off with solvents? Thanks.

BTW I don’t use infusion on this part. I just use a simple vacuum bag and then apply a 20 ton shop press on top pushed against mirrored stainless steel because its flat and then turn the part around and do the same thing. If I could spray a clear coat I would, but like I said, the solvents would take it right off.

#6

you have a flat sheet in a press and only one side is shiny?

Can’t you just mirror polish two pieces of aluminum and then sandwich the carbon in the press? A flat sheet should be easy. I usualy do sheets on glass and the glass side is always great. I’ve done some with glass on both sides but, in larger dimensions it starts to be a pain. A press would be the way I’d do it if I had one.

On other parts that aren’t flat, like car interior stuff, I’ve made the part, then sanded with 220 till it’s even, coat with resin, sand, coat, sand, coat. Finally sand down to fine grit, then polish or spray polyurethane, then polish.

#7

what wax are you using on your mold?
whats your process for clear coating?

if you demold, hit it with 600-800 wet sand then wipe it down with acetone
air hose it down and shoot a clear.

#8

[QUOTE=sammymatik;55719]you have a flat sheet in a press and only one side is shiny?

Can’t you just mirror polish two pieces of aluminum and then sandwich the carbon in the press? A flat sheet should be easy. I usualy do sheets on glass and the glass side is always great. I’ve done some with glass on both sides but, in larger dimensions it starts to be a pain. A press would be the way I’d do it if I had one.

On other parts that aren’t flat, like car interior stuff, I’ve made the part, then sanded with 220 till it’s even, coat with resin, sand, coat, sand, coat. Finally sand down to fine grit, then polish or spray polyurethane, then polish.[/QUOTE

I’m pressing the carbon fiber onto the part while its in the vacuum bag. Does that make sense? I’m not making a flat panel if that is what you are thinking. Can you still vacuum bag and suck resin out in between to polished plates of aluminum?? I’ve never tried it. As for coating and sanding over and over… it just sounds like a pain in the ass. It would take days it seems like to finish the small parts I make.

Also still need to know if Polyurethane can be takin off with solvents like acetone, paint thinner, etc?

#9

Also still need to know if Polyurethane can be takin off with solvents like acetone, paint thinner, etc?

Short answer is no, 2-component paints are solvent resistant.

#10

I thought you were making flat plates. I’ve made plates between two pieces of glass and it worked fine. I just got some thing aluminum sheets to try it, but now that I think about it, I should just use pieces of acrylic since it’s shiny to start. Since the flat pieces I need are cosmetic, I haven’t been concerned about sucking out excess resin. Truly the best way to do it is to use prepreg and a heated press or vacuum bag and an oven.

So I’m confused about what you mean. In your first post you say you put your ‘flat parts’ on a polished piece of steel? So you are not making flat parts? You’re using a mold?

If your mold is high gloss, the parts should be as well. Unless you’re doing an overlay onto parts? In that case like I said before, you’ll have to sand and coat and then spray with polyurethane. Unless you have a mold with a gloss finish you’re not gonna get an out of the mold finish. That technique is a bitch and takes a while, but the parts looks great when done right. I’m not sure if you’re selling these, but if so, charge for it.