Hi Guys, This is a recent development on my Workbee Machine, when I move the machine up in the Z-axis it suddenly starts grinding and struggles to go up and down. it seems to be when it is up high and is smooth again once it get back down. I have uploaded a pore excuse for a video, I can make a better recording if that would help, trying to use the controls while holding the phone haha. I took the gantry apart and cleaned it then put it back together, also have played around a bit with the backlash nut but still seems to have the same issue. I also ran the motor with out it attached to the gantry and that seems to run fine. Any thoughts would be appreciated. Cheers, Adam D.
What control set up have you got? Are you using soft or hard limits? I ask because it looks as though the Z axis is trying to go beyond its full travel. Alex.
You may have a loose wire to the motor. If not all wires are connected it will be jerky and make a grinding noise
And the noise comes off the loose front plate of the (unofficial) router mount when it is run into a hard stop.
Thanks so much for your comments guys, I moved away from using my Z-stop as it couldn't find a good place to put it that doesn't take up Z axis space I could make something to fix this but I haven't run into any problems not having it in use atm. I don't think it is beyond its full travel it should have another 20mm at the bottom here and it also happens going down in the Z but my video is pretty poor I was setting up a better one but might have found the solution. I swapped out my Y-Motor with the Z-Motor and it seems to be running smooth now. I am just puzzled why it would be working fine for most of the movement then start grinding at other times I guess there is added torque needed when it is up high? so that is when it fails? I wlll order a new motor. Kind Regards, Adam D.
Came across this post when I was searching for a solution to a similar problem. I have an OXCNC with an Openbuilds Blackbox X32 controller and a nema17 motor on the z axis with limit switches. The motor would occasionally grind near the upper limits of its movement when homing but would also do it during machining operations, which would cause it to lose steps. I ruined a few workpieces this way as the machine drove the cutter across the work at the wrong height after grinding. Checked wiring for faults with a multimeter - none. Checked for mechanical impediment - none. Temporarily rerouted Z axis motor cable out of the way to limit any potential EMI - fault still present. The solve was Increasing the current slightly for that axis on the blackbox controller. Seems like the motor was under driven. The motor now runs warmer but it no longer grinds or misses steps. Wanted to post this in case it helps someone else. Cheers.
