Green Sand Molds

Casting metal is a simple process - you melt the metal, pour it in a mold, and let it harden. But the mold has to withstand the heat and pressure of the metal while holding it's shape. It's not as simple as it looks.

Making the mold.

For no particular reason, I decided to cast a small wedge and some ingots. Here I've filled and rammed the drag, and sprinkled it with diatomaceous earth as a parting compound. The flask is quite small, about 6" on a side, and 4" tall.

The pattern (a wooden wedge) and the sprue (3/4" copper pipe) in place, ready for ramming. I forgot to sprinkle parting compound on the pattern before I rammed it.

The mold all rammed up, and the sprue pulled.

The mold parted cleanly! This is the first time I've used diatomaceous earth as a parting compound, and believe me, it works better than sawdust.

I drove a screw into the pattern, rapped it...

And pulled it out, nice and clean!

The mold looks good.

I cut a runner into the cope to connect the sprue and the pattern.

The Ingot Mold

A simple ingot mold. I just half-filled a coffee can with sand, and rammed a bottle into it to make a round depression.

Continue to the furnace.


© 2003 W. E. Johns