[Leah]

Hello! Hoping somebody can help.
I am using House of Molds 7-dice set molds to cast some fun dice. I’m fairly new to resin art and am learning as I go. I started with UV resin and have had pretty good luck with it.
HOWEVER… I wanted something more versatile so I recently bought some Super Clear Resin Obsession casting resin.

I have not been able to shake the TINY bubbles in my castings. Only in the top half – so they appear to be floating to the top and then sticking.
Here is what I have tried, based on reading through these forums:
-warming resin and hardener in warm water bath (still in a plastic bag) for 10+ minutes before beginning to mix
-warming molds and pouring warm resin into warm molds
-using vibration to try to coax bubbles out

-I am also curing the resin in a toaster oven at about 40degrees for 1.5 hours. I am not sure if this makes it worse or better??

I can’t use a heat gun because these are closed molds, so it wouldn’t be able to reach the resin inside.
I’m losing my mind here – I have done at least 5 casts which all have varying degrees of tiny bubbles inside and on top of the cast. I can’t paint these properly because the paint meant to stick inside the numbers just sticks in the little bubble indents.

Please help!
-Leah

[Katherine Swift]

Hi Leah,

I’m sorry to hear things are going as well as you had hoped. You are doing several things right, so let’s see what else you can try here.

I have a few questions for you:

1. Is the resin bubble free before your pour it into the mold?
2. Are you filling the stem of the mold with resin as well (i.e. overfilling the mold)?

[Steve]

A pressure pot will remove any bubbles in the cast. They are around $80.00. Of course you’ll need a compressor also. Hope this helps.

[Leah]

Hi Katherine – The resin does appear to be free of bubbles when I pour it. I have been swirling a bit around the outside of the mold before I fill it completely, and I am also filling the whole top so it has a rounded sort of bubble at the top of the mold. I have found it shrinks down enough that if I don’t do this, it will leave the sprue too small to allow to sand the die to the correct shape.

[Katherine Swift]

You must have been reading my mind! This is exactly what I would have done in this case. I’m anxious to hear how the new castings come out.

[Leah Frampton]

The problem is, I was already doing that. It didn’t fix the problem. So… I’m at a loss.

[Katherine Swift]

Oh ugh! It sounds like you may need to try pressure casting.

[Author]

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