Vacuum degassing RTV silicon DIY help

[dave05]

just wondering if any one has good plans or direction to building a vacuum degassing unit

i see some people are using old refridgeration compressors

any help or links appreciated

many thanxs Dave

[jetski]

I have done these types of prototypes for a long time. I know the industry has said you need to degass. Here is my solution (that works) using a paint pot and an aircompressor follow these steps. 1. Mix silicon as normal. 2 pour over your part I prefer clear silicone with a tape parting line and a marker line on the tape (to cut to). 3. put the part encapsulated in silicon in the paint pot 3. clamp the lid down and put 150 psi to it. this closes the pours in the silicon. Every 15 psi of pressure increase cuts the bubble size in half. By the time you get to 150 all bubble are gone and you have a 10x better tool. It will also make more urethane parts because the pours are closed more. If you need more information email me at gsilberberg@progressive-plastics.net

[ookpic]

If anybody is interested
Depending on how serious of a degassing chamber you want you..

I was able to make a degassing vacuum by poking a hole in the top of a mason major and simply sucking out the air with a brake bleeder. i was able to pull a max of 27 in of mercury just enough to degass my HS III silicone

it cant boil water but it seemed sufficient for removing bubbles from the silicone. I was able to set it up in literally one minute and for only $22