First mold ever- fairly good, but issues

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#1

I finally managed to pull apart my wing mold. It popped off both sides surprisingly easy. I have a big white wedge I got from Fibreglast and it worked very well.

My mold is actually better than I expected. But there are a few issues. (see photos- I haven’t trimmed it yet or cleaned off the clay, these photos were taken right after I pulled the plug from the mold halves)

These imperfections are somewhat deep, probably about as deep as a quarter is thick. Do I just use Bondo to fill it?

Also, the surface is far from “glass”. Do I sand it smooth, or should I shoot some 2K primer on it and sand it like I would the plug? I used white gelcoat first when making the mold, and it’s pretty thick.

Thanks.

#2

if i were you, i would fill the imperfections with some bondo, sand the entire mold and then clearcoat it so it would have perfect surface

of course if these imperfection are only in the flange i would just fill them with some bondo and leave them and i would polish the surface of the actual mold

#3

What you see is alligatoring. This is due to the first layer being slightly undercured.

Next time, make sure you pick one or more of the following:

-more heat
-more hardener
-more even layer
-thicker layer
-less humidity

Also, why is your mould not shiny? Was your plug shiny?

#4

Plug was, and still is shiny. When I sprayed the PVA, it never flowed out and was bumpy. I think that is the issue, but as this is my first mold, I’m not sure.

Thanks for the feedback guys. :smiley:

I’m finding that the PVA will come off and leave a smooth surface underneath, but the stuff clogs sandpaper like nothing I’ve ever seen. Is there a better way to get PVA off my mold? I’ve gone through two sheets of 150 grit sandpaper and don’t even have the flange clear (obviously I used too much PVA…)

#5

The PVA will wash off with water.

#6

reminds me of a client which I supplied polyester trailer parts to. The parts were still covered in PVA. He used an angle grinder to get it off, as he found no solvent which took care of the PVA. He was to be found covered in polyester dust regularly.

When I told him nice warm soapy water would do the trick, the look on his face was fantastic.

#7

:smiley: :smiley: It’s been a long day but that made me laugh, thanks!