Guys, I have been running the Workbee 1000 for a few months now and not have too many issues. Today, I started running a job and immediately noticed the x axis grinding to a halt between moves (missing steps I would guess). I tested about 10 times and the same issue. I then just jogged the country axis manually and noticed the same grinding and stalling. I disconnected the lead screw and found now catch points. I then went in and lowered the acceleration from 100 mm/sec down to 50 and all is well. Moved up to 75 and all is well. Worked all the way to 200 and thought maybe that wasn’t the issue. Any thoughts? thanks Chuck
Which controller do you have? Does the motor stall - almost right away - only when moving fast - only under load - how is the current adjustment on that axis set at present
I am using the black box. It seems to stall at the beginning of the move. Was running a lot of air runs so no load and still saw the problem. The current pot is set fairly low ( maybe quarter turn). I just run a bunch of air runs and ramped up the speed to almost 400ipm and no stalling whatsoever with the acceleration at 200. I am more confused now. is the stepper starting to fail?
Just ran a couple of gcode files and all went well until the final move to the zero position. It stalled in X. DRO reads 0,0 but it’s about 3” shy of getting to X zero.
Sounds like loose wiring to me. Check all the connections/connections/joints on the X axis motor wiring - intermittent faults tend to come and go as wiring makes contact and later wiggles loose again
Checked all the connections and found everything was secure. I set up a surfacing path so I could watch it run for a while. About 3/4 of the way through the x axis stalled. This time I noticed a high pitch whine when it happened. the stepper motor is slightly warm but certainly not hot. Chuck
I played around with it today and I have concluded that the steppers were advancing too fast. I could consistently cause the problem while jogging and make it go away. At 6500mm/min the x axis would stall and make a loud whining noise and when I dropped it down to 5500 it would go away. The bizarre thing is I have been using 6500 for months without any issues. Is there any logical reason I would need to slow the x axis down after months of use? Additionally I have the y axis set at max speed of 6500 and have not seen any issues thus far. Should I be reducing this setting as well? Anu suggestions would be helpful. Thanks Chuck
Hard to say what exactly it could be, but 6500 is exceptionally fast for a TR8 leadscrew, rather than finding out why you are slower now, I'd more interested in how it worked so fast in the past It could be that some setting like acceleration or max travel speed were limiting the speed without you noticing much (you dial in 6500, but Grbl limited it to 5000 for example (see Max Rate gnea/grbl), and since you weren't really sitting there clocking the speed with a radar gun, assumed it was doing 6500? Other than I'd just put it down to things "settling in" - some dust on the rails, plastic shavings in the leadnut, things just wearing and betting in I'd say
Ok this is getting frustrating. I set the max rate down to 5000 and the acceleration to 150 on both axis and run multiple jobs without any issues. Today, when running the second 3D carving of the day the x axis starting acting up again. Axis stalled and destroyed the project. I decided to run it again with the z axis raised to see if it faulted in the same spot which it did not. Job was almost done and once again the x axis stalled and lost its position. I then went into GRBL settings and played around with speeds and could only get the x axis to stall when operating manually with a speed setting of 10,000! Yes 10,000! I don’t get it. Also, I noticed today that when I turned everything on the red exclamation mark was on the Blackbox x axis and I had to turn off and restart to get the axis to home. Help!
Fault indicator indicates - short circuits in motor wiring - overcurrent (power on peak may have just put it over the edge, it depends on motor inductance, etc, just turn down a bit if its not one of the other things) - overtemperature - undervoltage I do doubt that though, I have not seen a motor attached to a machine reach that actual speed (Even if you set max feedrate and G1 F10000 - acceleration will probably not peak there on a 1m travel with the weight of a spindle on the X axis) (; we need a mini traffic cop aiming a radar gun at the axis as it comes past (;
I understand your point about the speed and was only trying to point out what I have tried during the troubleshooting process. I can tell you at 10,000 it flew across the axis in 500mm move! I am going to change our the cable between the motor and the black box.today. If that doesn’t work should I change out the motor??
Well fair enough, but do remember stepper motors torque changes with RPM (low rpm, high torque - as it speeds up, torque drops off) ideally for high RPM you want to use Servos. For steppers, the sweet spot is closer to 3000mm/min rapids on our machines. Great you can rapid at crazy speeds, but in the name of reliability, it helps to be a little more conservative.
The normal gcode speeds I run are 100-150ipm in hardwood and for pine up to 200ipm without any issues. This recent issue came out of the blue after I had finished running over 100 cribbage boards. When I turned everything on again this morning the red exclamation was on the x axis again. I just changed out the cable and am testing a file in the air.
New cable did not make a difference. Half way through the file the axis stalled. I ran it again with the current pot turn all the way up but it too stalled part way through the file. The motor did not overheat. I did have a spare motor so I changed it out and tried another run and the same result! Not sure what to try now. Blackbox failing?
(; that will light up red soon Yes, but the Driver chip, has a tiny little silicon die inside it, thats the thing that overheats (; Haven't had one do that yet, but I guess nothing is impossible. When it skips, fault LED on or off? (I only see mentions of it being on at power up above)
I just put a meter on the yellow and green leads coming from the black box and the voltage reading is unstable. It was at 8volts (pot turned all the way up) and as I kept the probes on it dropped down to 6 and bounced around from 5.7 up to 6.3. I checked the z and y leads and they are holding steady ( plus or minus 0.01 volts). All of these are about 1.0 to 1.2 volts. I then moved all the axis and went back and checked the voltage. Now the x axis has dropped down and is bouncing between 5.1-5.8. I checked the other axis and they bare steady at the same readings as before. I moved all axis one more time and now the x axis voltage is up to 7.9-8.4 and all others are at the same readings as their original. I checked the power supply and it is holding right at 24.1volts. it’s got to be something in the Blackbox! thoughst?
The output is a chopped sine wave, you need an oscilloscope to really analyse that - bouncing around doesnt mean broken, it could just be the constant current chopper doing what its supposed to to maintain constant current (by varying the voltage) Maybe http://support.openbuilds.com/support/home can help, do include link to the thread to avoid them asking the same troubleshooting again)
Could be a wheel that is too tight or bearing failed? Dry PTFE lube your acme screws? On the bigger motors 75% on the current dial is about right, make sure your fan is still working and blow the dust out of the blackbox. Cheers Gary
