Instructables

How to make a crucible capable of containing molten aluminum?

I am working on melting aluminum/copper and i have enough power to melt them...only problem is something to contain it...I do not have acess to welding equipment/ceramics and any advice on how to make/obtain a crucible without special order would be nice! Even if its not a real crucible but can serve as 1!

purduecer5 years ago
Well...as an initial thought, I went here and found that Aluminum melts at 660C. Therefore, any material from that table melting at a temperature above 660C (preferably considerably above) is a good starting point.
Problem with most crucible materiel isn't melting, it's burn threw from the heat (think of it as very aggressive rusting). The bottom of steel medical oxygen tanks works great. The tanks can only be used for so long and get thrown away/recycled.
cnicolo jtobako9 months ago
I've used medical oxygen tanks, and they work GREAT... probably good for at least thirty melts of 12 lbs. aluminum each. Burn through is a problem, but it takes quite a while to get through the 1/8" steel of the tank I'm using.

Disposable propane tanks, which are about 1/32" thick burn through in as few as 3 melts. It's quite dangerous, as it may not start dripping until you take your crucible out of the furnace...

I've recently started working with copper, and the higher sustained temperatures are forcing me to look beyond steel... Not excited about shelling out big bucks for graphite crucibles, so any ideas will be much appreciated!
fierwall54 years ago
what you do is you go to home depo and get an empty paint can 1-3 dollars what i herd and you can either melt it in their or in a ceramic pot like the ones for plants pretty sure you can get one that is sealed all the way  and ya just go on you tube and you will get some ideas
Prfesser5 years ago
Some have used empty disposable propane cylinders, but thin steel will not last long. I ruined my first furnace by attempting to melt scrap in a (fairly thick) stainless-steel "can", the kind used for salad dressing in restaurants. The steel burned through and the molten metal found its way to the bottom of the furnace. Use extreme caution when working with molten metal; you need a place for the metal to go if it decides to leave the crucible before you're ready. There is a book by Vince Gingery on making crucibles at www.lindsaybks.com. Hope this helps, Prfesser
lemonie5 years ago
Steel will work well enough. But if it's thin like foo-cans it doesn't last all that long before burning-through.
These guys made a heavy steel crucible

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