X Motor set screws vibrating loose during tuning.

Hi guys.

Just a quick note that might help others experiencing difficulties during the setup and mechanical tuning phase. I have been fastidious at getting the modules running freely on the lead screws, both at the sub-assembly phase and during final mechanical tuning. I was quite astonished when I watched the Stepcraft U.S. videos on adjusting the XZ module pre-load where they had to jerk the module in both X and Z extrusions to get it to move. :ohmy: Before I saw this, I spent ages adjusting mine ensuring that they ran free with just a light push from one finger or moved slowly and smoothly under gravity.

Anyway, I ended up with all lead screws moving freely with very light force applied between index finger and thumb.

Nevertheless, I was having difficulty getting the X axis sorted and already experienced one problem with the M4 x 4 mm set screws (part #45) working loose on the X axis connector (part #58) presumably as a result of the motor buzzing at the ends of the track.

I substituted the supplied self-colour set screws with stainless steel ones that I had filed the point flat to give a larger surface area to mate with the flat on the motor and screw. I note that they fitted the thread very precisely (neither loose nor stiff).

However, while loosening off the gantry uprights and tuning, I had two further issues with both set screws vibrating themselves loose very easily. I ended up dismounting the x axis motor, cleaning all parts with isopropyl alcohol (part of the issue might have been lubricant getting in to the thread helping it work loose easier) then putting a small dot of cyanoacrylate superglue on the set screw point only, not on the threads!.

On reassembly, there were no further problems.

Regards.

Doug