Hi,
I increasingly use a 4th axis in rotaty carving jobs. For a series of foam carving jobs i've made a lightweight 1 metre long trunnion to hold 200mm thick foam blocks to carve at 45 and 90 degrees degrees. The problem is its not got enough torque to hold itself in place at different indexed degrees when milling material.
I bought 12nm stepper and HSC86 closed loop driver to run a 1:1 HTD belt and pulley. The stepper is standard 12nm 1.8 deg and the closed loop driver can go up to 110vdc and 70ac. Its currently ungeared (Gearing this would have been better granted but time and budget got in the way.) The trunnion bed is about 8kg set back 30cm from the axis rotation.
As a 12nm stepper it should surely be able to hold better than it should. Without the obvious advantage of gearing where should I look first to improve its holding?
Any thought or suggestions how to improve the mechanical, electrical or software setting most appreciated.