Getting a mold off a porous surface.

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#1

Hi, this is probably a simple question for you guys here, but I’m not sure how to deal with it. I have a race seat that I was to pull a mold off of, but the surface finish is rather porous. Let me be clear, I’m not ripping off a design. I’ve spent thousands on different race seats trying to get comfortable in my car but have always wanted something different (Ive severely broken my back in the past so most seats dont hold me without discomfort) so I took one that I felt had the most potential and started cutting, fitting, and testing til I was happy. Now that I have a shape Im happy with I want to start over and make a new piece, just hand laid glass, but first I need to make my mold. The portions of the seat that are still original have a porous finish that Im sure will make the mold a permanent piece. I tried taking a picture, but not sure how well it will show up? I think they are tiny voids that happened during vacuum bagging but not sure? I’ve thought about using a harder modeling wax and trying to rub it into the surface, but wanted some opinions first.

Thanks in advance!

#2

Hi PBR

I’d just keep it simple. Use a high build 2k automotive primer as your spraying rub with your finger and it will fill 99% of them on the first few coats. Let it dry for a few days give it a quick wet rub with 400 ( trying not to rub through to much createing more pin holes).
Then give it a top coat of gloss 2k. This will give you a nice surface to pull a new mold off. 5 to 8 coats of TR wax and build your mold. :slight_smile:

Tim

#3

Duratec polyester surfacing primer and a squeegee. Spray or brush on a coat of Duratec then squeegee into the pinholes. Let it cure for a couple of hours or you can force the cure a bit with heat. Sand to remove ridges and whatnot. Spray with Duratec again to get a good surface. After it has cured, you can sand and buff it to whatever finish level you desire.