Vacuum casting - testing the system

Vacuum casting…
System checks.

  1. Is your sealing pad in good condition( high temp flat
    silicone pad Usually red in color)

  2. are you drawing at least 28" mercury on your Vac gauge
    before putting a flask on the Pad( to test… put your finger
    over the hole or a piece of silicone rubber to seal the vac

  3. If you are using perforated flasks… make sure the flask
    flange is absolutely flat and both sealing surfaces are clean.

  4. if you are using standard (non perforated ) flasks… have
    you on occasion used a wide belt sander on the flask to make
    sure that the sealing surface of the can is perfectly flat.This

  5. if you are using a standard flask, you can greatly increase
    your vacuum casting suction by using the tyvac perforated flask
    liner… Available from

and also from This will allow you to
cast at lower temperatures and get better fills. I hope this
helps some people who are having problems

Daniel Grandi