Re: AUTOCLAVE design

Posted by bpfink on December 12, 1999 at 09:37:57:

In Reply to: AUTOCLAVE design posted by Jack Davis on January 11, 1999 at 16:49:31:

I fully agree with Jesse Brennan and know I certainly would not trust my personal expertise enough to make an autoclave. It is basically a high pressure cooker with high pressure explosion problems if not fully safe guarded.

Your question about the expansion of the wax in the mold is a good one and is also one of the reasons the ceramic shell users love that system. The wax touching the sides of the 1500F degree shell sides melt the wax and let it run out before the inner portions have had a chance to expand and to do their dirty pressure cracking deeds.

There are many other ways to totally prevent or minimize this expansion so I want to refer you to the post on wax working at http://www.artmetal.com/village/chat/main/transcrp/980423MN.htm This also covers some folks systems of using things along with or instead of wax as the main media and thus being able to semi remove the interior bulk, vents and sprues before the piece even goes into the kiln.

Also making a 'whipped wax' (by whipping like an egg white as the hot wax starts to cool) for the core areas or even surface portions both saves on total wax used as well as gives the final model microscopic air room to expand into while it melts in the burnout kiln.

ETC ETC

Using these systems I have no need for an autoclave.

Good luck

bpfink

Sculptural Wax Working for later casting:

http://www.artmetal.com/village/chat/main/transcrp/980423MN.htm