holy bubbleing mess batman!

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#1

So, I figured I should vacate my clear casting resin so I can make my turnsignal, since my CF shroud mold failed horrible, and I went back to the drawing board.
I put it in the “belljar”, and the entire cup filled up with foam.
I dumped some out, still the same.
I ended up with only 1/2oz, and the entire cup still filled with foam!!!
Do all epoxies do this? Should I be using a VERY large “belljar” and large mixing cups?
I ended up giving up, heating the epoxy up, and waiting.

my cup was a 16oz one, in a ~20oz vac. jar.
I only started with 4oz of epoxy!

#2

I have never had an issue with degassing in my little belljar. How much vacuum were you pulling?

#3

True you dont need alot of vacuum for degasing. Less than 20" should be good and if you cycle it of the first part of the process it will let the bubbles come out.

Also try the use of a shaker table to get the bubbles out. Use a drill motor on a table with an offset weight on it and attach it to the table. Use rubber mounts under the legs to get more shaking.

For stiring, Dont whip the resin like you would with a cake! Keep the stir stick against the sides and bottom at all times using slow scraping/stiring motions. Even rapping the cup on the table surface could get some of the bubbles out.

#4

oh.
Um.
29"

#5

ah, I was doing about 29" or so.