So, Degassing is the process of getting all the air out of the mixed resin. This leads to stronger parts with a better cosmetic finish – you aren’t fighting tiny bubbles that appear in the resin, or that start to appear as the resin warms through the exotherm and the gas expands.

It’s simple to do – you put the resin in a chamber – evacuate it and watch the resin bubble up as the air comes out. As the bubbles near the surface, you let a little air in to equalise the pressure, the bubbles subside and you continue until under full vacuum, no bubbles appear.

However, it’s NOT SIMPLE TO DO: I lied. There are subtleties to this, and if you just open the tap carelessly,it’s easy to let the air in too fast and get resin everywhere. Also, you end up shooting air into the resin you were trying to clear of the damn stuff. This is also how you trash a degassing chamber, and they aren’t cheap.

The following youtube video I made illustrates this with water. Read on to see how I fixed this with a simple 3D Printed part.

So, I designed and printed a part that moved the air and vacuum over to where it was needed:

So, using some gum-tape to fix the air-guide in place, I now have a degassing chamber that lets air in without worrying about shooting it back into the resin.