Thread: Melting aluminium

I can't resist this thread. I had a small non ferousios foundry that was geared to The Model Engineering game. Speaking as one that knows any molten metal and water do not mix. I had two explosions with ally once when there was water in the ingot mould and I was pouring the remnants of a melt into the mould. this was only a small amount of metal but gee it was spectacular I still have a mottly cap from this adventure. The secon time I was melting scrap (not cans) to make Number Plates. No need for quality. The last pieces ito the 15 Kilo crucible were some radiator fittings. I pushed them down and there must a been the tinest amount of water only dampness and the result was even more spectaculat.
The only problem I found with melting from Ingots was the size of the beasts. I bought ingots that you broke in half with a sledge hammer and these went into the 15 kilo crucible. This was of a maximum size I could handle by myself. Even when I used ingots I used a cleaning agent to bring a the gunk to the surface of the melt. These tablets were pushed to the bottom of the melt and bubbled away furisly. Most were pretty toxit not recomended for enclosed spaces. But they did work. Ally cans have an ally in them to make the metal extrude around a former so are not very good for quality work.
Finally a word on furnaces for those fool hardy adventures. The stuff to use for the lining of the furnace is Kaowoll. I am not sure if this is the correct spelling but it is the way it is spoken. This stuff reflects the heat and thus reduces the melt time. it comes in a blanket up to an inch thick. Wraped around a drum 1 layer is enough. You have to be gentle with it when removing a crucible but with a normaly asperated blow torch you are in busines. My furnce looked terrible but it did the job.
If any one is interested I will talk about moulding sand and other foundry bits later on.
Yoursn 4-6-4

yep Kaowool, it is used a far bit at the smelter