I made a reproduction part in AL using my propane forge. Mine is a 12" pipe about 18" long on its side (Larry Zoeller design) For a cruciable I used a 2"x4" sq tube 5" long with a bottom welded in, l used a 1/2" rod about 40" long welded on the side. Pay attention to the previous warnings about water or moisture. I had a green rammed sand mold (baked). Melted Al rivets in it, skimmed off the dross with my borax spoon.Poured with a Carrhart coat, welder gloves and a face shield and probably should have done more. Read lots, find someone who has done it before, look at some You Tube videos, be safe. It only takes one mistake.