In the last couple carves I have had an issue with my X Axis where the carve is running fine, then out of nowhere the motor is locking up as if it was running into a rail or something solid stopping its path. Once the direction change happens the gantry moves with no issue for roughly 4-5 inches and then does the same thing. When I stop the carve and manually move the gantry I can get the motor to repeat the lock up issue even when moving in single inch increments. I have checked the entire length of the machine...have no wires or objects anywhere that would snag or stop the movement of the X Axis at all. Once I let the machine sit for a bit, even leaving the power on it will not have the issue when I move it manually but as soon as I run a carve the motor will lock up. Starting to think bad parts inside the motor.
It does not go into a higher pitch. It locks up hard as if it was running into a rail or something that would stop its progress.
Disconnect the motor shaft , and spin leadscrew by hand, and feel for spots where it binds up. Then investigate mechanical components around that spot
Unhooked the motor, was able to move the gantry across the machine completely by hand with no binding rail to rail.
With motor on its own, repeat test and listen to motor. Does it stall as it speeds up What do you have set as Max Rate and Acceleration values in Grbl Settings for that Axis? OpenBuilds or 3rd party motors?
With motor on its own the motor does not stall as it speeds up. The motor is at speed when the locking happens. My motors are the Openbuilds Nema23 High Torque motors. I have not modified any Grbl settings from the initial setup from openbuilds. I also went through and checked wiring and have no issues there. No exposed wires, no severe bends that could have caused a break.
You should still check the GRBL settings - it can happen that the EEPROM gets corrupted in some circumstances. Post them here if you can.
GRBL Settings $132=90.000 $131=1270.000 $130=1180.000 $122=350.000 $121=350.000 $120=350.000 $112=1000.000 $111=3500.000 $110=3500.000 $102=199.100 $101=198.110 $100=196.260 $32=0 $31=0 $30=1000 $27=5.000 $26=250 $25=2000.000 $24=100.000 $23=3 $22=1 $21=1 $20=0 $13=0 $12=0.002 $11=0.020 $10=115 $6=0 $5=0 $4=1 $3=0 $2=0 $1=255 $0=10
So, the remaining difference (as mechanically its not binding, with motor standing still its not) then may be "it binds up when the motor is moving the machine, and in turn tugging on wiring" indicating a loose terminal or wire broken off inside insulation that intermittently loses connection. See docs:blackbox:faq-identify-motor-coils [OpenBuilds Documentation] but note all wiring may test fine until tugged on just right
Even though there is no stall on the speed up of motor, would a break still cause it to lock up its movement when traveling at full speed? When it does the lock up the motor does not lose power, it acts like it is trying to push through a jammed up spot. The only way I can think to give a comparison is like if it were to hit the rail and would try to keep going but cant. I had the motor do this connected and disconnected from the screw.
I also see where I can reset EEPROM. Should I look into just doing a full reset on that this evening once I am back to the shop?
It can, as the next step is interrupted, the magnets inside jump to the nearest hard-step Your settings looks very default, corrupt eeprom would have weird values in there Try dialing it back a little as a test because of: Stalling at speed does stop the motor, though after stopping you can usually still hear a whine coming from the coils inside
I went ahead and rewired the X Axis and ran a test. The motor sounded fine, did not get any lock ups however still got the same result as far as the carve moving off of position by close to 5 inches. The only thing left that I can even think of would be the g code file itself is corrupt or not saving and loading into CONTROL correctly.
Slippage is usually either loose setscrews on shaft coupler for that axis, or the Acceleration/MaxFeedrate needs tuning if its stalling under high speed travel moves
I just went through everything. I reset all settings on CONTROL. Did a new calibration of steps after adjusting tension on the screws. Have a new motor and new wire on the X axis. Attached is a video of the issue. This is happening during the carve and this video shows it with me trying to manually move the machine in 1 inch increments, not even a full run across the machine.
Mentioned very early on in this thread. Can be heard clearly in your video Dial down the acceleration and max rates. $110-112 and $120-122 (pick whichever axis is stalling). Tuning procedure is explained in the Grbl wiki.
classic speed stall, but before changing anything it's worth increasing your current pot by 1/4 a turn if that is at stock. Then turn your max speed down 500, IDK if jog speed is independent of max speed in open control, but turn that down as well. Cheers Gary
