Hello All,
I've been getting the stuff for my foundry started back up again. Last summer I cast quit a bit of stuff. The sand I use is called Petro Bond. It has oil in it instead of water. When a casting is pored the oil is burned out of the sand that comes in contact with molten metal. When a flask was broken open I carefully scraped out and seporated this burnt sand and saved it. I had 2, 5 gallon buckets of this used sand that needed oil added back into it so it could be used again. The process of conditioning the sand is called Mulling. Here is a picture of the muller I built to do this job.
The sand can't just be mixed it has to be mashed togather. Most mullers use wheels to run over the sand. This one has blades that mush the sand against the side of the muller. This was made from a propane tank and some left over projects. That's why it looks kind of like Frankenstein :-D
Later,