Are you casting metals?

[CNCadmin]

If so what for and how you doing it?

[Klox]

Now I am not. But i am curious about castings, foundries, moulds and patterns.....

Klox

[castguy2003]

What would you like to know? I have over thirty years as a Patternmaker and for the last five years I have been directly involved in the foundry business.

Castguy2003

[Bill C]

Ever heard of using pulverized glass for a cover for melting and casting tin bronze?

Bill C.

[Klox]

Castguy,
Do you perhaps can give me some pointers on how to make mini foundry for aluminium?

Klox

[castguy2003]

TO Bill C, I am assuming you are refering to the use of material that is put on the top of open risers to retain heat.
TO Klox, There are a lot of plans on the net and in books for small gas fired furnaces. You will need some advice on gating and risering your pattern.
Gas entrapment can be a problem when pouring aluminum.

[Klox]

Yes i know about the gas entrapment. I used to share my premises with a patternmaker and i must say that patternmaking require a lot of experience on gating and risering especially when doing sand castings as sand can get flushed into the mould as the molten metal gets poured....

See you....
Klox

[9566317]

I have started a small Aluminum permanent mold
foundry in my shop.I have 2 1200LB electric furnaces.Finding information on mold design has
been the bigest problem.Yuo can ask 5 differant people for plan and ideas and not one will be the same.Seems to be a bit of a "black art" simular to heat treating.(started doing this 20 yrs ago)
I think I now own every book that even thinks of
pouring aluminum but it still all boils down to the shop in particular to figure out what works for them.

[Splint]

Bill C,
I know someone who uses glass to seal malten alloy from the atmosphere, if I recall correctly it needs to be food grade clear glass, not dark glass as used in some beer bottles as this i think has too much iron in it which can contaminate the melt. The glass helps keep in some of the alloys and when the melt is ready to be poured, the glass is skimmed off and discarded, when this happens white smoke comes off the melt which is when some of the alloys are burning off. The glass doesn't need to be pulverised, just give it a hit or two with a hammer and it will all melt down and form a skin over the top of the melt. You might find more info here http://home.iprimus.com.au/cmckeown/index.htm
Cheers
Splint

[Hobbiest]

9566317,
How are your perm molds constructed? Do you make them?

[BIG AL]

This may help, at least I've found lots of good info on this site.http://www.valleymetal.org Check out casting demo with Tom and other usefull pages here also.

[Hobbiest]

Thanks for the link, I will check it out when my crying baby goes to sleepy time! Not sure it has anything about permanent mold though.