Keeping the Chuck on the mill

[S.Nickens]

I didn't even consider the possibility that you would be trying to mill with a Jacobs chuck. Ginger is right, doing this is a very bad approach, not to mention dangerous. End mills should always be mounted in the correct size R-8 collet. I know everybody has a budget, but you can start with a popular size like 3/8"or 1/2" for less than $20, and add to your collection as funds become available. An eight piece set will run you around $160 ( 1/8" - 1" by 1/8", most std sizes ), and you can always check E-Bay. SAFETY FIRST!