A first project to break in a new furnace

Before you laugh at the Halloween themed furnace, I could not help it, the container was the perfect size and had for free. I thought the paint would burn off after the the third time the furnace has been fired, but it seems my refractory is that good, despite the sloppy novice looking concrete work


So recently, I built the furnace I was talking about that would be much better than the one in a previous post, and here it is, In the above picture. Unfortunately, I didn't get any pics of the building process. This new toy of mine has a lining of 3000 deg F rated castable refractory, 7 3/4 diameter burn chamber, and is souped up with a Ron Reil propane burner. The first firing consisted of charcoal and a bit of forced air to burn out the center form- a core on which paper would be wound onto at the mill. The second firing was a test of the propane burner I built during which I melted a couple handfuls of brass keys. It was a roaring success.

This post details the third firing, for a more meaningful project. I have a good friend who has been battling throat cancer for a while now, so I decided to make him a little something because he is interested in what I do when I melt metal.

Last night, I carved the pattern for the piece to be cast from lost foam. I have not yet built a hot wire foam cutter, so a big bread knife was used to cut the shape. After that, a small screwdriver heated with my propane torch made an engraving tool, followed by sanding with some emery cloth. As you can see in this pic, I covered part of it in drywall compound. Why not the whole thing? Because this project is also a learning experiment for me.

The next day, the drywall compound was reasonably dry, so I fired up the furnace loaded with aluminum drink can ingots I made in the past.

Once the metal melted, I skimmed off the dross. There wasn't a lot of it either. The pour went well. Here is the raw casting:

And cleaned up a little:

It is just a little decoration with my friend's initials and a cancer ribbon. Despite the casting coming out perfectly as it should, My head slumped in disappointment, And I learned I have a great deal to learn about workmanship. This is my third lost foam casting, but the first on something I want to do, rather than screwing around, and It is back to the drawing board.