Throw away the swarf.
It will only create lots of slag in melting. That's a waste of expensive heat and volume in your crucible. Also throw the poop cans where they belong, that's not good aluminum for casting. Pistons on the other hand is good if you can get them cleaned first. Heat throroughly before putting it in the melt though. There are lots of crevices that can hold oil or moisture and create an explosion.
If the material is clean and in reaonably large chunks, you will get a casting with close to the original characteristics. You *must* degas, or it will be brittle and with tiny gas pores in it. (There are now less harmful degassers than Hexachlorothane.)
Do not let the melt come in contact with iron, then it will generally not be useable for anything but plaques and figures that will not be machined. |