casting aluminum

[losthelm]

has any one done small number casting aluminum pieces? I have a design of some heavey weapon pomel weights and such I would like to cast. not shure about what i can use for a casting medium thought.

I was plaining on using plaster of paris for the mold wood frame two part mold.
as a crucible i figured I would use a ceramic vase.

for the casting furnace I was planing on just building a hard wood fire and pumping air under it as you would a forge.

with a shroud keep the heat focused on the crucible.


would this work?

are there any ideas on how to do this better?

I am trying to do this ultra cheep with almost no budget.

[Thomas H]

hmm, you could try carving a soapstone mold but i am unsure of the type of heat it can withstand. Another option, could be to carve from firebrick in two halves?? i have done no casting, these are only ideas. try www.backyardmetalcasting.com

[Edward Harrison]

my experiences have been useing stryofoam forms and pack them into sand then when you pour the molten aluminum in the sand, the styrofoam forms literally evaporate (stay clear of the fumes, they are harmful to your health) then once it is cool in the sand you can let the form out and take your piece. Clean it up and then you are done.

[Justin Livio Guidi]

I have - now don't laugh - a coffee can foundry to melt my aluminum. Complete with BBQ charcoal and a ShopVac blower. I have done a few small casts out of some dental plaster (the correct term isn't coming to me...) and some dental carving wax. The whole founding process is fairly easy, and getting ahold of small bits of cast aluminum to melt down yourself shouldn't be too hard, they're everywhere if you look hard enough. I was using aluminum cans for awhile. They worked, just not well.

I haven't made too much progress in this, I wanted to move onto pommels like you, but rather use brass or bronze.

Good Luck!

-Justin

[Thomas Powers]

Soapstone is good for fine silver----*MUCH* hotter than Al.

A ceramic vase is not appropriate as a crucible.

Lindsay Publications has a complete series on making and using a backyard Al foundry with information of home build melting furnaces using charcoal and green sand casting.

Molten metal os one place where minor details can scar you for life; please do a proper research and technique before you save a couple of bucks on materials and spend $20,000 on Dr bills! (Not to mention "the pain, the pain, the searing pain!")

There are several forums on casting out there where folks can step you through the process.

If you are near central NM; I'd be happy to myself.

BTW any scrap Al is not suitable for casting; you want to cast Al alloys that were designed for casting---pistons are usually a good supply.

Thomas

[Nikos]

First piece of advice. SAFETY! Heavy apron, gloves, and FACE SHIELD!

Your best bet for casting pommels and crosspieces out of aluminum is to use old pistons, lawn chairs, or any other source where the aluminum has not been painted. Soda cans contain too much dross to be a decent source of casting aluminum.

Any type of furnace that will reach approximately Farenheit 1200 will suffice to melt your metal with.

Use an old cast iron pot as a crucible. You want something that isn't going to fracture when it gets hot. A simple mistake can lead to a life altering injury when you're working with molten metal. And make certain you've got something other than a leather clad hand to pull the crucible out of the furnace with. You'll want tongs, or something else long to use.

And as a mold, you might consider using sand. There are ways of making your own green sand, or you can purchase it from a local jeweler supply shop.