Possible to accelerate the shrinkage time?

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#1

Using polyester resin (even with vinyl ester epoxy resin) I need to make thick pours. Is it possible to accelerate the time it takes to shrink and the majority of the outgassing after it has cured?

Right now i make it cure as slow as possible so heat doesn’t hurt the expansion so much. Is this correct?

I have many successful pieces, but I’m letting it set for about 2 months before I do any finishing work. Half-millimeters are like the grand canyon regarding “size” on this piece. I am hoping to reduce this amount of time.

T.I.A. :slight_smile:

#2

Find a better low shrink polyester resin

or use epoxies?

#3

I have tried 7-8 different options for this, and there is one that gives the best result but i have to wait for it to shrink before i can work with it.

would baking it help any? would it weaken the resin? what temperature is best if i bake it?

#4

Does the part need to be clear? I think there are several options you might be able to try.

#5

Doesnt need to be clear, must be able to get a high level of polish

#6

I was going to suggest a low shrink resin like I use for tooling (AOC LPT-68000) but if you need to polish it, forget it.

There are some direct tooling boards you can machine and get to a high polish finish. Axson makes a couple of varieties, epoxy and urethane. I haven’t used either (yet) but I have seen the end result in urethane - very high gloss. They also supply a wide variety of resins so they may have something you can use. I’d ask them about urethanes because shrinkage is nearly zero, at least in the ones I’ve used.

#7

i will look at Axson, i havent heard of them. I am still new to the different options of resins. I looked into different types, but i didnt know that the vendor makes a difference.

thanks!