Hi Reading John Campbell's book. He is a strong advocate for counter gravity casting. This is where the molten metal flows from the bottom of the crucible out to the mold, against gravity. There are various methods of achieving this in a commercial foundry. The aim is to avoid pouring all of the dross and other contaminates floating on the melt. It is a method that can be applied to any metal. What I find interesting is that some methods use current passing through the melt to pump the metal. The current flow generates a force at 90 degrees to the current direction. This is a super elegant solution but commercial systems would be out of reach $$$ of DIY. I know this method of pumping molten metal with just current was applied in a research nuclear reactor that used liquid sodium metal as a coolant. The sodium was contained in steel pipes. Two terminals were welded to the pipe (one each side of the pipe) and a large current passed through the terminals. The liquid sodium is a much better conductor than the steel pipe, so most of the current passed through the sodium, not round the pipe. If the pipe is an insulator (eg. alumina ceramic) then a half turn coil can apply the magnetic force to the molten metal. Contact with electrons is not required. So conceptually, pumping molten metal is not that difficult but possibly beyond the reach of DIY. Has anyone achieved counter gravity casting in a DIY Home Foundry????