ummm... I have a shell mill with inserts, I want to change them out for some better suited to working on aluminium castings. How do I identify the insert type I have?
Most decent shell mills should have a code on that gives a clue as to the insert shape required. I think its usually the second letter, or it is on lathe tools. The next letter is usually geometry positive or negative rake. Then its down to measuring size and radii then grade of insert.
You may find the shell mill works better on aluminium with only one tip in place, almost as a flycutter if you are trying to achieve a good finish on a facing cut.