• How To Make The Mini Metal Foundry

    There are 4 cups in a quart, yes? So, if I have a mixture that is 21 cups + 21 cups + 15 cups, that is a total of 57 cups, right? Divide that by 4 and we get 14.25 quarts. How is this "just enough" to fill a 10 quart bucket to 3" from the top? I followed the instructions precisely. Mine overflowed and it is taking longer to set. I presently have a 2x4 over the top to hold the 2.5 qt bucket down with a bucket of water on top of that. When I cleaned out the bucket that I made the mixture in, it seemed as if all of the sand in the remaining mixture had started settling to the bottom, and I KNOW that it was mixed in well to begin with. I hope that this is not happening in the foundry mixture as well.

    To be fair, there is space between the sand grains for water, and there is a chemical reaction with the water and plaster where one molecule of oxygen is released, so there will be less than 14.5 quarts. Still, if it is supposed to fill the 10 qt bucket in such a manner that it is full when the displacement of a 2.5 qt bucket is added, that means a total of 7.5 quarts of material was expected. I had almost 12 qts. AND, it did set just fine. I was maybe a bit impatient, but it set, I removed the bucket and drilled the airway. I had just a bit of crumble around the inside edge of the airway when I inserted the steel pipe, but nothing too bad. The interior is indeed very smooth, and I can feel the heat being given off by the chemical reaction in the plaster. Very cool! Also, using my 2x4 method, the small bucket was flush with the steel bucket. (You have to run the 2x4 under the handle of the steel bucket.) I used a sharp edge to level off the plaster mixture so that is now totally flush with the steel bucket, and I kind of like the way it looks.

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