Though I've been waxing high on lost foam casting for some time, I've always revered and looked up to a "higher level" of aluminum casting, green sand split casting. The following recounts my adventure therein.
Using google as our guide, me and "The D" found quite a number of green sand casting resources, namely Foundry101 and Eugene Sargent's Sandcasting Primer. Both excellent resources.. that we probably could have stood to study a little harder before taking on the project.
It's not that we're against reading instructions, or well written detailed how-tos with helpful photos or graphics.. Heavens no! It's more to do with the fact that the learning process so often simply boils down to just doing something, not reading about it, and hoping to try, or matching every single instruction. So we just skip straight to the actual learning part.. which usually means we do more trial by error than we probably could with reading everything extremely well.
But where's the adventure in that?!
- Build two strong interlocking hinged frames to hold the sand and mold
- Mix the green sand clay together in the right amounts
- Pound the green sand into the bottom mold to test
- Add the items to be molded (A rubber spatula handle, and a marble egg)
- Sprinkle "parting dust" on the top of the molded items and sand, to keep the top sand from sticking to the middle
- Add the top frame and pound the rest of the green sand to form the top of the mold
- Carefully separate the two frames and remove the items
- Then using a pencil, etch the troughs in the sand for the metal to flow from the runner to the cavities
- "Drill" the holes for the main sprue to the runner, and vent holes for the steam to escape from the molded cavities
- Pour the aluminum, and retrieve the finished product!
The following pictorial is a catalog of mine and "The D"s adventure in green sand casting.