[PHSS]

Today I was cutting a file, two small 2 inch square brackets with a radius out of 16 gauge sheet metal with fine cut consumables at 150 ipm. Every time I run the file it will jam on the z axis the motor stalls out. Contacted tech support, was told to check the alignment etc. I took the motor off, gear rack out and cleaned it with a wire brush to remove anything that could be in the teeth, did the same to the spur gear. reinstalled the motor and gear rack, aligned it parallel to the travel of the torch holder (I pushed the gear rack tight to the spur gear and snugged it, then moved to the other end and middle until the feel of the carraige moving was the same, then set the spur gear off the rack with a tiny amound of backlash, so now, without the drive belt on, I can push the carraige with torch, lines etc with my pinky finger easily but it still stalls out on the cut regardless whether cut is turned on the AVHC. The only thing I can think of is the belt is too tight and will check that on Monday. Any ideas what else I could look for before assuming it is the motor. I have had no problems cutting on slower feedrates, are these steppers (I assume as it is a small shop 4x4 table with no frills) able to handle feedrates in excess of 150 ipm?

[PHSS]

Ok need more help. Turns out it was the X axis jamming, with tech support help, went through the following things to try to fix it:

• Square the table - Done, 1/16th out of square
  Check gear backlash making sure spur gears do not have any weight on them - Done, 4 thou clearance between the rack and gear
  Check Drive Cards in controller - Done, swapped connections no change
  Check Motor - Done, swapped motors on axis, still no change.
  Check Inside Controller - Done, blew out any dust per recommendation
  Remove drive shaft and test with only motor turning spur gear - Done, problem fixed.

So I checked the driveshaft for damage, and spur gear for damage, use a dial indicator and no runout at all. reinstalled and it won't work. To recap the motor drives the gantry X+ but when it transitions to X- it often sits there and buzzes. This only happens at feedrates in excess of 100 IPM. When I mean often I mean every file I run but not on ever X- move. without the motors energized I can push the gantry without any resistance whatsoever so at this point I can only summarize that the motor is shot, which would make sense since I noticed that some of my students whom I trained to use the machine were pushing the gantry while motors were energized and not using the jog, I have heard that is very bad.

At this point unless anyone can suggest something else out I plan to purchase a new motor to replace this one and try it. At the same time I am also going to purchase another motor mounting bracket, pulley, belt and mounting hardware and cable to run another X axis motor on the opposite side and eliminate the driveshaft using the motor I have, much like the never models have. I plan to add more weight to the table including air nozzle system to keep the racks clean, oxy fuel setup and a fume extractor so I can use the extra power. While the motor I have appears to not be pulling its weight, adding a new motor and using this one as well, will definitely improve my available torque at high feed rates, which appears to be the problem.

[Mike@Torchmate]

If you swapped the motors and the problem continued, I would highly doubt you have a "weak" motor(s).

Pushing the motors while energized does not damage the motor in any measurable way.

You haven't mentioned if you tested the motor cable, or the cable coming out of the motor. If there is a loose or intermittent connection anywhere along the motor cable, or in the pins on the connections themselves, it could produce the exact situation you are describing. Worse, it could actually damage the motor drive board that this particular motor is plugged into causing irreparable damage and you have to buy a lot more than a motor cable.

The only reason why all the motor drive cards could be "weak" would be a possible power supply problem in the drive box itself. If the drive cards are being under-voltaged this might cause the problem you are describing as well. I haven't seen it happen before, but you never know.

The last thing could be the computer itself. If the computer is lagging in the processing of step/direction commands to the signal generator, then it could be skipping steps, particularly during the deceleration/acceleration of the machine, causing the motor to hesitate momentarily (not moving at all) and then try and start instantly moving at full speed above 100 ipm. The motor can't physically accelerate 120 lbs from dead stop to 100+ ipm and would just bind. This would only happen, or happen more, when running a g-code program.

To test this, I would take another computer and install the drivers software onto it, then copy the setup file from the existing computer over to the new computer. If it works fine on the newer computer, the older one needs to be cleaned up or exchanged for a better one.

-Mike

[PHSS]

I switched cables, no change

I ran on clean, that was just reformatted and had windows reinstalled laptop, no change. How do I test my electronics further to see if the drive cards are fried or connections not working. Will I have continuty on some of the connections on the connectors and if so, which ones etc.

[Mike@Torchmate]

I switched cables, no change

I ran on clean, that was just reformatted and had windows reinstalled laptop, no change. How do I test my electronics further to see if the drive cards are fried or connections not working. Will I have continuty on some of the connections on the connectors and if so, which ones etc.

You can check the output voltage to the cards, each card should be reading 36v DC, and the drive box fan should be receiving 24vdc. If these numbers are much lower than that, I would suspect the power supply to be the problem.

If a drive card was "fried" you would know it, that motor port wouldn't work at all, and it would blow the fuse on the back of the unit.

-Mike

[bakerj99]

so your x axis (long axis) is "stalling" and making a buzzing noise? have you checked the gantry to make sure that it IS square to the table? i had the same problem and the gantry was the factor. if thats not it im very curious to what it would be, so post what else is happening and surely someone has a "hey i did that and this was the problem" post.

lets figure this out
bakerj99