Explain to me the Z axis capabilities of the machine you are using. Is +/- .001" stretching the machines intended use and or capabilities?

Knee jerk response here is....well I'll wait for a little more info.

your problem is not the collets

you need to install backstops to accurately position your pieces in the collets

then when you load the piece into the spindle you can finely adjust each individual spindle by testing the depth of each hole

may i also suggest that the collet is cleaned before you load the next piece

i am a screw machine engineer with over 25yrs experience with a vast knowledge of all types of screw machines

if you require any further assistance on any matter contact me please

Thank you for your help, Do you know where I can these backstops? We are using spring loaded knock out pins right now, these are ok when you are just reaming a thru hole. I am new to the chuckers but not the acme bar machines I have over 30 years with them. But the loading and un-loading I am not to familar with. Any help you can give would be great.

Can you explain more about the backstops and where I can purchase them? Also how will the parts eject?

Thank you