I melted metal today!
A little while back I stumbled upon this YouTube video that was just too cool to pass up. The video showed how to make a simple aluminum foundry. Watch the video here.
I just had to give it a try. Last week followed the directions in the video and made the crucible, and today I tried it out for real.
Here is the basic setup for my first attempt.
That arrangement is basically what was called for in the video.
45 minutes later, this is what I got out of it.
Why does it look like that, you ask. Wasn't the idea to end up with nice neat biscuit-shaped ingots?
Yes, but there was a small wrinkle which was not covered in the video.
I managed to get the heat cranked up hot enough where I could drop cans through the hole in the lid and they would be disappear in a couple seconds. It was quite spectacular, actually.
I put probably in excess of 50 cans in to the fire. I could see into the crucible through the hole, but there was a layer of slag on top of the molten metal that obscured it completely. The slag was a very strange un-metalic texture, almost like styrofoam, but glowing hot. The real question I faced whenever I looked into the furnace was " is there anything under that layer of slag? How much is really in there?" The slag was also decieving in that it didn't seem to be melted no matter how hot I got the steel pot. It eventually became a real nice cherry red. By that time I had fed a garbage bag's worth of cans into the furnace and decided that I just had to pour it out. I had a muffin tin handy, as suggested by the video. I pulled the crucible out and poured it into the muffin tin. Thats when Murphy showed up. I had no idea what was going to come out of the steel cup; all I had been able to see was the "fluffy" slag on top. The fluffy slag came out first, in a big screaming-hot mass of crud, into the muffin tin. Into the ALUMINUM muffin tin. Then right behind it came the stuff I couldn't see, which was the actual molten metal I had been trying to make. The molten metal hit the thin-walled muffin tin (do I need to remind you that it was also aluminum?) and almost immediately melted through it, then it hit the aluminum bench below that and kept on going, all the way to the ground. So I ended up pouring everything onto the grass.
(Murphy was very disappointed that I wasn't trying this on my composit deck)
All that happened in the space of two or three seconds. It took me half a minute to realize what the steam coming from under the bench was from. I doused it with water to cool it down and retrieved my prize from the grass.
It's got dirt and grass embedded in it, but its the real deal!
Murphy's contribution was letting me use an aluminum muffin tin instead of a steel one. The muffin tin is warped, melted through, and I am pretty sure it is fused to the aluminum workbench, which is also warped.
The forge, crucible and lid seemed to have survived intact ,but a bit dirty. My next attempt is going to be to melt dowm my "blob" and turn it into something cool.
So how much did I get out of all those cans?
Here it is on my kitchen scale. A smidgen over one pound.
Was it worth all the trouble?