Hawkeye..... you are so right,,, Thank you. May I add one safety comment. If there is a problem and your melt runs out the bottom hole of the furnace be sure there is something safe under it to catch that melt. I have a SS pan (like a restaurant style) filled with nice dry perlite. it can hold a full crucible full. You don't want that melt to run out on anything wet or concrete etc. ZERO injuries ONLY fun!!!!!
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Cast Aluminium Parts
- Thread starter buster
- Start date
Hawkeye..... you are so right,,, Thank you. May I add one safety comment. If there is a problem and your melt runs out the bottom hole of the furnace be sure there is something safe under it to catch that melt. I have a SS pan (like a restaurant style) filled with nice dry perlite. it can hold a full crucible full. You don't want that melt to run out on anything wet or concrete etc. ZERO injuries ONLY fun!!!!!
- Joined
- Feb 16, 2013
- Messages
- 29
What's holding your bricks in the lid?
- Joined
- Jun 17, 2011
- Messages
- 2,069
If you look closely at the edge of the lid in the second photo, you can just make out a groove at the edge of the angle iron frame. The angle iron is cut so that one side is only about 1/2" wide. Cut the groove around the bricks, then bolt the frame together with the narrow side in the groove.
- Joined
- Dec 17, 2012
- Messages
- 630
I would be very leery of home mix refractories. Most are not going to be very durable or well insulating. If you are stranded on a desert island, go for it. When you can buy the real stuff cheaply, it is a waste of time. I bought some 1"x 20" fiber insulation on ebay for $9 a foot and a couple insulating firebrick for $8 each to make a small oven for heat treating and maybe a little forging.
It doesn't take that much heat to melt aluminum if you have good insulation. Insulated fire brick for a base is preferred. My personal favorite is not to use firebrick but fiber ceramic insulation (Kaowool is one name) for most of it besides the base. It is a lot lighter and easier to make something where you can lift the whole thing off away from the crucible instead of reaching down into it. Look at plans for Raku Kilns. Electric ceramic kilns put out more than enough heat to melt aluminum. Instead of building one, I would go that way. I just don't like messing with gas. For small quantities, the little glass fusing kilns are quite nice.
If you are looking for real power for melting other metals, you probably want to jump straight into oil burners. I wouldn't mess with building a burner for propane. They are too cheap. Look for the ones that they use for burning brush, melting tar, and melting ice. You can pick them up at Home Depot or such. Those are up in the range of 180,000 - 250,000 BTU if I remember correctly. This is $20 at Harbor Freight.
The only bad thing about some of the casting stuff is paying shipping. Castable refractory is nice but expensive to get shipped. If you are lucky, you live somewhere with a furnace and boiler company nearby where you can buy without paying shipping. If not, Budget Casting Supply isn't too bad (their prices include shipping).
If you have more money than time, Foundry101.com sells a nice little starter kit. It includes burner, crucibles, furnace, some tools and a small cope and drag with some sand. Not too bad at about $500 when you consider shipping. It gets bad when you are shipping sand and cement.
It doesn't take that much heat to melt aluminum if you have good insulation. Insulated fire brick for a base is preferred. My personal favorite is not to use firebrick but fiber ceramic insulation (Kaowool is one name) for most of it besides the base. It is a lot lighter and easier to make something where you can lift the whole thing off away from the crucible instead of reaching down into it. Look at plans for Raku Kilns. Electric ceramic kilns put out more than enough heat to melt aluminum. Instead of building one, I would go that way. I just don't like messing with gas. For small quantities, the little glass fusing kilns are quite nice.
If you are looking for real power for melting other metals, you probably want to jump straight into oil burners. I wouldn't mess with building a burner for propane. They are too cheap. Look for the ones that they use for burning brush, melting tar, and melting ice. You can pick them up at Home Depot or such. Those are up in the range of 180,000 - 250,000 BTU if I remember correctly. This is $20 at Harbor Freight.
The only bad thing about some of the casting stuff is paying shipping. Castable refractory is nice but expensive to get shipped. If you are lucky, you live somewhere with a furnace and boiler company nearby where you can buy without paying shipping. If not, Budget Casting Supply isn't too bad (their prices include shipping).
If you have more money than time, Foundry101.com sells a nice little starter kit. It includes burner, crucibles, furnace, some tools and a small cope and drag with some sand. Not too bad at about $500 when you consider shipping. It gets bad when you are shipping sand and cement.