Interchangeable ball mill

A tool comprising:

• an interchangeable cutting member and an adapter to which said interchangeable cutting member is adapted to be replaceably mounted;
• wherein:
• the interchangeable cutting member comprises a substantially ball-shaped body with a cutting surface, wherein the body comprises a female screw-thread formed therein;
• the adapter comprises a male screw-thread portion configured and arranged for screw-engagement in the female screw-thread;
• the interchangeable cutting member comprises at least one coolant or lubricant fluid passage, said coolant or lubricant fluid passage ending at the cutting surface of the ball-shaped member;
• the adapter comprises a coolant or lubricant fluid delivery duct, said coolant or lubricant fluid delivery duct being in fluid communication with said coolant or lubricant fluid passage when the interchangeable cutting member and the adapter are screwed together;
• the adapter comprises a first conical surface and the interchangeable cutting member comprises a second conical surface configured and arranged for mutually centering said adapter and said interchangeable cutting member, when the adapter and the interchangeable cutting member are screwed together.