Smallest Reasonable End Mill

You can always use a 1/8 V bit for that type of work, not the same thing but the end result is close enough.

Project_Hopeless wrote:

I'm relatively new at CNC so I'm always nervous about breaking bits. For MDF or pine how small a bit would you recommended running?

I rarely go below 2.5mm, but I have a 1000rpm spindle.

Try a feeds and speeds calculator and see what looks reasonable for your spindle speed.

I imagine that a sloppy machine might break very small bits, But otherwise there is no reason to worry.

This chap thread-mills m2 holes on a full-size industrial mill: www.f1-2000.co.uk/index.php?f=conrods

I suspect the real limit is how long you are prepared to wait to nibble away the material.