Getting the best surface finish

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#1

Hi folks

So I’m doing a pretty simple layup of flat CF via resin infusion. I’m just starting out with composites having taken a few short courses at my local tech college and have been playing around with glass fiber and chop strand to get the process and technique right.

I want to make CF boards pretty soon but need a really good Class A surface finish. Everybody says laying down on a glass actually gives the best finish but as I want to make several boards at a time, I’d like to use a mould that I can make a few of. Having heaps of panes of glass around the place is definitely not ideal.

Are there any good alternatives? Some kind of sheet metal? Fibreglass with tooling gel coat?

Thanks!

-Sam

#2

Sheet metal would definitely work, but in order for it to be perfectly flat, you may have to use a thicker and possibly very heavy piece. Probably at least 1/8" I would think. Melamine coated particle board is another option, but it may have a texture to it. The fiberglass mold would also work, but you may have to use glass or sheet metal initially to make the mold so you have a perfectly smooth and flat surface.

#3

Glass is great mould material that can’t be beat really.

I use an old sliding door for wet layups, infusion and pre pregs. The door still has the alloy frame on it.

#4

As Fasta said, glass is great. I use a 3mx1.8m outdoor dining table. Released with Frekote so I virtually never have to do anything to it other than a top up coat every 10 pulls or so, and when it isn’t being used I’ve got a cover for it so it can just be used as a table. Even the wife is happy!

Really anything you’ve got is going to take up space, but I find glass is so tough and easy to look after.

#5

Just a tip if you use regular glass since I had one crack caulk or use some type of adhesive and put a bead on the bottom and cut a piece of poly wood or something else to support it.

#6

I had a local glass guy cut me a thicker piece of glass and softly round the corners, then he sent it to get tempered. Tempered glass is a lot tougher than ordinary glass.