We have a propane fired crucible. Talk to Fired Arts. You’ll have to provide the propane as we don’t store any on site due to fire code regulations (also why we don’t have oxy-acetylene welding set-up)
In short, yes. Fired Arts has this furnace, and it is used from time to time by Paul ( @Hardsuit ) to teach classes. I am unaware of the other activities surrounding it, but I hear tell there are some.
I am unaware of other furnaces if there are any.
Photomancer that is great advice and will help for future castings too.
I’m casting it on plaster. I have a part made out of MOLDLAY that I’m using as the positive. Once I melt it away from the plaster I’ll pour the aluminum.
I’m doing it this weekend and I’ll send pictures of it once it is done. Thank you all!
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Some while back Walter did a Al casting project/experiment.
The following picts should give you an idea of the equipment used.
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This has often been something that interests me. If anybody ever ends up teaching a class on it, I’d definitely sign up (hint hint).
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Thank you artg_dms!
And I second benhubel statement.
And I’ll third that! 
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Keep in mind when creating your master that you need to allow for shrinkage and finishing.
Shrinkage in cast aluminum is 5/32" per foot (or about 1.3%)
In addition, you should allow for additional material to be trimmed off to smooth/polish the surface after casting.
Allowing a 3% to 4% total oversize (in each dimension) is a good rule of thumb.
If using a 3D-printed model, you can simply scale it to 104% in KissSlicer before printing.
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HankCowdog
I read that a couple of times and since I don’t have tight tolerances and I was feeling generous I scaled it up 5%.
Since this part is only 2.5", if I read that correctly, you might take a look in Jewelry/ Small metals. I taught a sand casting class last year using DIY greensand and I am working up a class for petrobond sand casting and Delft clay casting.
We are also getting an electric furnace for melting small batch metals. We also have a member that sometimes brings her personal electric furnace for casting classes. As the crucible is generally used for only one type of metal you would probably need to buy your own crucible.
If you can make a wax model of the part we can get up a lost wax casting class or you can make the original in the new 3-D printer to use instead of a wax model for investment casting.
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Yeah-yeah-yeah… I hear you. Let me get the pottery and sewing stuff settled, and I’ll finagle something. Think June-ish…
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I should avoid commenting with only five hours of sleep. Carry on. @_@
Did you ever cast this part? I’m interested in how the moldlay worked out for you.
well, for the life of me I can’t get the negative to work. I’m making it with plaster of Paris and I think I’m heating it up too fast. It starts collapsing after about 10 minuted of heating.
As far as the moldlay, it takes a while to get the settings right on the printer. I got it to be good enough but by no means clean like with PLA.
After several attempts I’m ready to pay someone to cast it for me. Anyone you know that does castings?
I’m nowhere near any kind of experience level of doing casting but are you pulling a vacuum on the plaster of paris before you pour it. I’ve seen videos of that done to where they pull a vacuum to get rid of the excess air pockets.
Hi TBJK,
I have done it but I didn’t notice a difference. I think there is a steep temperature gradient between the outside and the inside of the mold.
Did you manage it like you wanted? If not I can try to show you how I would do the sprues tomorrow. I someone will help make some crucible tongs I can do a grand can smelting/lost foam lesson sometime this break.
No aluminum in the jewelry casting equipment. It’ll cause severe pitting on silver and other metals with contamination
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Hello there, If I was casting this part. I would cast it upside down. I would print it using wax printer. I don’t know how to use the wax printer, OR I would make the part out of another material and cast silicone rubber around it to make an exact duplicate out of wax. Then we incase the wax in plaster because of your shape, I’d have the legs exposed out of the top of the plaster i.e. cast it with the legs as shown pouring plaster around the base and up until it fills the cup part. The entire thing can then be heated to allow the wax to melt out leaving your empty mold. We can flip the heated mold, pour in aluminum. Hope this gives some kind of idea.
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Are you heating the PoP to drive off the water prior to the pour? Or at some other stage in the prep/for some other reason?
Hey Rashon I really like your idea. The mold is too bulky and the legs are deep inside the mold. I think your approach would make it easier for the wax to melt away because it is not deep inside the mold. I’ll give it a try.