I finally finnished my testing prototype of my metal melting furnace. Did a few casts to get short rods for the lathe work and noticed a big problem. I used washed play sand as itwas the finest sand I could find locally. The result was good in shape but very bad in terms of surface quality. For another test I used the leftovers of my crushed perlite and mixed it bentonite and the surface was really smooth - but using perlite is not really an option. Real green sand is hard to get in my area and the postage costs for a 20kg bag are just too high on top of it. So, before I start hunting down all sand and soils shops nearby: Is there a proper name for extreme fine sand or a good alternative for a reusable casting media?
Asked by Downunder35m 3 years ago