I use the Dewalt 660. Everything has been great until 3 days ago. I reworked my board to be grbl and use Easel software. It is just easier for me. Everything was fine until a few days ago. I can get everything line up and then I turn on the Dewalt on and then the bit slowly descends. The bit is securely tight. I can turn it off and it will stay put but as soon as I turn it back on, it descends. Is something loose or is the motor bad? Is there a setting in Easel that I need to set? Or do I need to go into Universal Gcode Sender and change a setting?
I love the machine and my son just bought his kit and I have others that are interested in but this has ruined some wood already. I need a fix.
Itās the vibrations from the motor causing the z to slowly rotate and allow it to drop. Mine does it too.
The way I combat this is, I start the gcode first and then I turn on the spindle as itās moving to the first hole/spot. Itās not ideal, but itās working for me.
If the stepper motors are active/engaged, then the Z wonāt drop. I think thereās a G command you can send that would enable the steppers. So you could run that command, then turn on the spindle, then start your Gcode.
An alternative approach would be to set your x,y,z 0 point. And then use the LCD to jog the machine up and down .1mmZ This should energize all the steppers once you make the movement. I āthinkā once you jog the machine, the steppers will stay energized. You should be able to then start the spindle and not have the Z slowly drop. Iām just guessing at this as I havenāt tested any of it myself.
Mine was doing the same, and I worked around it by pinching the leadscrew between my fingers when I turned on the spindle, then when I started the job with my other hand, let go of the leadscrew. Very lowtech, but worked.
I have since added a Iot Relay and the code to the beginning and end of my gcode to turn the spindle on right after I start the job, and off at the end. Problem solved there, and I donāt have to be standing right next to the machine when it ends a job or risk the z falling and cutting through my work piece.
The Iot Relay was very cheap, and is a great upgrade for the system.
Iāve been trying to source some springs to fit over the Z-tubes in the hope they address this issue. I saw a pic (on this forum) where someone had done that and it seems like a reasonable fix. Havenāt had any luck finding an appropriate compression spring yet (quite weak and large ID) - just about ready to break down and try winding a custom one from music wireā¦
Thereās apparently an issue with skipped steps at high speeds with a 1 start leadscrew but I havenāt encountered it on my setup and it definitely stops the router from dropping when the steppers are powered off.
lmao just covering the bases. I am not immune to new ideas, I didnāt get that vaccine when I was young. Did anyone ever test if the skipped steps problem exists at low microstep values? Iām thinking it might be marlin causing it and not motor torque loss.
Jeffeb3 suggestion makes the most sense - change a grbl software setting (rather than grabbing the leadscrew while the machine is on, or adding springs).
I am using grbl with a CNC 3018 (and my MPCNC) and setting the āStep idle delayā to 255 via the command
$1=255
keeps the stepper motors on all the time, which stops them from moving (unless grbl is used to tell them to move).
Did anyone ever test if the skipped steps problem exists at low microstep values? Iām thinking it might be marlin causing it and not motor torque loss.