Metal Working: Designing and Making Pistons

Learn the details of pouring, feeding and the solidification of iron and aluminum piston castings so you can do it yourself.

Alluminum's long freezing range alloy
Iron pistons are easily cast by using small gates on the top edge of the casting and no risers. Aluminum pistons, because of solidification shrinkage, are more difficult to cast. Pouring temperature and the placement of gates and risers are very important. 
Illustration Courtesy Chastain Publishing