clear glossy finish without mold?

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#1

I touched on this question my first post but it kind of got lost in the other responses so I thought I would ask it again in it’s own topic…

Pretty basic question: How can I get a clear glossy finish over carbon fiber without using a mold?

I’ve seen people suggest rolling on extra layers of resin, applying a spray-on gel coat like duratec. However I’ve recently seen a suggestion of applying a layer of regular fiberglass cloth on top of the carbon and then sanding it down smooth prior to applying an automotive style clear coat. I know fiberglass becomes transparent with the application of resin, but does it get THAT clear that you could still see the carbon cloth perfectly through it?

What would you guys suggest as the best approach for an amateur with no specialized tools (gel coat spray guns, wire rolers, or anything else really).

-Matt

#2

If you do try the fiberglass method stick to cloth that is 3oz weight. It should be totally clear once wetted out.

I reverse molded a couple parts directly off of oem original parts. I brushed on epoxy resin after and block sanded it. Much work involved. This is the reason we prefer using molds :slight_smile:

#3

thanks for the reply… I’m not even sure how I would make a mold for the part I need. The shape itself is super simple but I’m planning to use a urethane foam core.

Here’s a rough rendering of what I’m trying to build: http://www.mr2-power.com/cabinet.jpg

As you can see it’s basically a hollow box with four sides (the front and back are open. I’m not sure how I could build a mold that would provide finished surfaces on all faces and still allow me to remove the part :slight_smile: I could easily do the four outside faces, but then I would have to build some sort of expanding insert to finish the four inside faces. But then I’m left with the small dimension edge faces.

If I could figure out an easy-ish way to build a mold for this part I would jump on it to avoid all the sanding :slight_smile:

#4

Do you need every single side to have a smooth finish?

#5

No, not really. Ideally I would like the outside faces (obviously) and the front face (darker edges facing the bottom-right direction in the picture). The inside can be rough as can the back edges. To me the problem is the front face. I guess I could build a five-sided mold with radiused intersections. I didn’t radius the front front edges on my model but they will have the same radius as the four long edges on the outside edges and no radius on the inside edges. I should also mention that I probably won’t have the little cut-out on the back of the top face. Just a straight box, the same on all sides