August 14, 2002
I wanted to improve the melt time on my 'Quick and Dirty' foundry, but I wanted to try to use what I had on hand.
I figured I needed to block off some of the excess air flow through the brick pile and from underneath. I had a piece of light plate steel I had cut from a water heater tank a while back just begging for a use. It slipped right over the King Kooker.
To block air from underneath the burner I poured dirt into the top until it seemed to be enough to do the job. It took about 2 five gallon buckets full. I pushed this around with my hands to clear the burner and leave an air path.
Then I restacked my firebrick inside the steel liner, leaving room for my new steel pipe crucible. Well I couldn't stop there! I hooked up my new-to-me 40 pound tank of propane and fired that mother up!
I put the round plate up trying to block some of the heat. The gray piece at the top is a piece of an aluminum car rim left over from a previous melt. I used it to block some of the opening there.
I figured the real test would be to try to melt those bronze propane tank valves the propane dealer had given me. (He was throwing them away!) He said it took too much time to get the steel out to sell them for scrap.
I removed the steel screw and the die cast handle and pitched 'em in the pot. They had a small tube that looked like copper or brass, but it went in too. The small rubber and plastic parts burned out without a whimper.
It took a real long time for anything to happen. Finally, I thought to try to get a little more pressure out of the regulator. I had to use pliers, but I managed to get another couple of turns on it. The sound level increased and the flame was visibly larger. The pot turned so red I thought it would sag, but it didn't. I thought it was not going to happen when I poked at the valves with a brass rod and they started to fall apart. A few more minutes and I was stirring a pot of brass with a lot of garbage on top. I didn't have a mold prepared because I didn't really expect it to melt. I have a cast iron muffin tin that looks like soldiers, so I preheated it.
It looks shiny because it is wet. It's just old rusty cast iron.
I turned off the burner and removed enough brick to get the crucible out. It was glowing so much; it almost hurt to look at it. (It had gotten dark outside by now) I set the crucible on the steel deck of my car-hauler trailer I was working on, and used a cast iron spoon to skim the dross. (More like shovel it out! There was a lot of dross.) I poured the soldier pan, but the melt was already starting to harden.
I had to pry this out of the pan! I am not sure of the alloy; it is a lot yellower than Silicon Bronze. The valves had an almost brown patina, but this looks more like yellow brass to me.
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