09-28-2020, 05:40 PM
I'm thinking of casting aluminum and I would like to use old soda cans. Will this ruin a clay graphite crucibal?
No, but as rleete said not a good source.
Any ideas where to find excess aluminum for melting?
Engine rebuilders. Pistons and connecting rods are high grade aluminum and small enough to fit in the crucible. You don't need to clean them up, just make sure to use enough flux. The piston rings can be removed with a bent piece of O/A welding rod. A small engine rebuilder is also good, but you have to break up the engine blocks and the quantity is usually not as high.
Can I temper my crucible in a propane forge like in the video?
Yes
How important is borax in getting my clay graphite crucible ready?
Very
I have a clay graphite crucible and a silicon carbide graphite one. What temperatures can they handle? What is the difference?
Been awhile since I looked this up. You should be able to find an answer on-line.
Are sand molds a good place for a beginner to start? Any tips?
Yes. Use water based casting sand. Much easier to temper. Put your molds on a piece a sacrificial plywood or OSB, NOT on concrete. Water expansion ratio to steam is 1600 to 1. Concrete is full of water. Think about it.
What are good ways to finish an aluminum mold? Polish? Sandpaper?
Do you mean a pattern? Either will work, but for sand casting the draft on the pattern is more important than the finish.
Be careful, very careful. A good pouring temp is around 1250 degrees F. Plenty hot enough to burn the crap out of you.
If you can still find a copy of the US Navy's Foundryman manual, buy it. Probably the most definitive reference for foundry work ever written.
No, but as rleete said not a good source.
Any ideas where to find excess aluminum for melting?
Engine rebuilders. Pistons and connecting rods are high grade aluminum and small enough to fit in the crucible. You don't need to clean them up, just make sure to use enough flux. The piston rings can be removed with a bent piece of O/A welding rod. A small engine rebuilder is also good, but you have to break up the engine blocks and the quantity is usually not as high.
Can I temper my crucible in a propane forge like in the video?
Yes
How important is borax in getting my clay graphite crucible ready?
Very
I have a clay graphite crucible and a silicon carbide graphite one. What temperatures can they handle? What is the difference?
Been awhile since I looked this up. You should be able to find an answer on-line.
Are sand molds a good place for a beginner to start? Any tips?
Yes. Use water based casting sand. Much easier to temper. Put your molds on a piece a sacrificial plywood or OSB, NOT on concrete. Water expansion ratio to steam is 1600 to 1. Concrete is full of water. Think about it.
What are good ways to finish an aluminum mold? Polish? Sandpaper?
Do you mean a pattern? Either will work, but for sand casting the draft on the pattern is more important than the finish.
Be careful, very careful. A good pouring temp is around 1250 degrees F. Plenty hot enough to burn the crap out of you.
If you can still find a copy of the US Navy's Foundryman manual, buy it. Probably the most definitive reference for foundry work ever written.