Quill Clamp

For locating the center of a feature using a dial indicator on a milling machine. Mounting diameter is 89mm and pushes against the 40 taper drive dogs. All threads are M5x0.8. The short "Universal M5 Flexible Magnetic Arm Indicator adjustment arm" is from China and costs $10 or $17 if you also want a magnetic base. Made in Europe these arms run about $100. The China quality internal machined surface finish need some polishing to make the clamping operation both positive and silky smooth. Takes about 10 minutes when/if you know how to do it. Without polishing the force/sliding internal surfaces of the China ones are a misery to own.
Added Sept 16 2020 a video link not by me on how to improve the arm.
https://www.youtube.com/watch?v=qnHfHl7LI7Y


The printed M5 clamping knob has a 4-40 internal thread for a metal bolt to strengthen it. A metal M5 bolt would be a better choice. Alternatively melt in a 4-40 threaded insert.

Printed in carbon fiber PC 100% infill at 250C on a 150C