Hi David,

Here is a youtube video showing the process of changing end mills and how they go into the machines, this happens to be an industrial lathe, but you get the idea. https://www.youtube.com/watch?v=DNbN1h2e5jY You heat shrink the tool into the collet, still have to wrench the collet assembly and nut down every time, about all this gets you is a set tool length.

As for steppers vs. servos (or closed loop steppers), you can make anything work if you want. Have the machine home before each tool change and you can get rid of any lost steps if they are happening. Only time I've lost steps is crashing into clamps and such, never cutting. My CNC mill (old Milltronics) uses servos and the only machine I've ever used steppers with is my Stepcraft.... not thrilled with steppers, but it works and I have yet to use it enough to warrant changing it out, either the steppers or the machine completely.

Quote Originally Posted by David Buchhauser View Post
Brian - I'm not sure I quite understand how these work. How are these retained into the spindle, and what is the function of the tapered end? Are the collet wrenches still required to remove and replace? Which end does the tool bit get heat shrinked into? Perhaps you could provide a photo or two showing one of these in use.
Thanks,
David