Quote Originally Posted by gustavus View Post
Well done, the aluminum from the motor rotors is not one I would prefer using.

My favorites are aluminum rims, engine and transmission scrap.

If you really want to produce some really nice castings source out Petrobond sand. it is so fine you can capture a finder print. Also you might want to ditch that steel crucible for a silicon carbide one.

Believe it or not the steel from that crucible is contaminating your aluminum. Aluminum which has other unwanted metals could give better pouring quality's but probably the opposite will happen where the quality depreciates.

Bad aluminum could freeze before filling the mold, become brittle and break like glass at the slightest bump.

I had a bunch of silver solder used for refrigeration that came in sticks, for an experiment added a stick to my aluminum melt. The finished casting came out fine but very brittle.

If it hadn't been brittle the one quality it did have ( tone ) would have made it a perfect alloy for casting a large bell.


Fishing weight mold.
Thanks for the info, I read about petro bond after I already oredered the clay to make green sand, we want to try it out.....I also was looking at different porcelain crucibles on line also just havent bought one yet....the one we used was just what came with the furnace and what we used because we were so stoked on making plaques, I hear ya on the purity and weak aluminum for objects of use , I was thinking more about the motor shaft aluminum for pouring my ignots to sell to the scrape yard ,I did quite a bit of reading up before I ever tried to cast pretty interesting stuff!

Quote Originally Posted by miked View Post
Great couple of hobbys. I like the old pu. Mike.
Thanks!