Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

My next attempt was another engine base, and this time I poured a little too cold, probably around 1340F, and should have been at more like 1350F.
The cooler the pour, the better the surface finish, but the metal must be hot enough to completely fill the mold cavity before it begins solidifying.

I think this defect is called a "cold shut"?
I call it a partial mold fill.