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Hi everyone,

Follow-up question to Mike's question...

I have been casting parts for about two years... simply doing, as Burl calls it "ambient casting". I do not vacuum pump my RTV. Mostly I have one part molds, some "glove" type molds.

My RTV molds seem pretty good, the level of detail matches my original model quite well (e.g. rivets, undercuts, etc). If I get a good pour of plastic, its near perfect match. About 2/3 of the time I get bubbles that I have to go back and fix with small batches of Alumilite (usually not related to mold details).

Based on this... my question, where would I get the biggest bang for my buck: pressure pot for the Alumilite or vacuum pump for RTV? I think historically I have read that degassing the RTV is the best thing, but my experience seems to be that RTV is quite forgiving, and that the resin is the problem area...

Any thoughts?

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