It drives fine 
without the belts on by hand
In that case itās either the motor canāt handle the requested torque or thereās something loose between the motor and the gantry. My guess is that the pinion gear worked its way loose which is what prevented proper transfer of motion to the belts.
When you removed the pinion gear did you happen to notice if it was not properly seated?
Can you confirm that the gantry moves freely and smoothly if you move by hand now?
Yes it was seated properly there is also a video the last one I uploaded 2 days ago showing me moving it while the motor was still attached and you can see the whole thing moving freely including the gantry.
It still moves freely now without the motor attached
I had her move the Y axis forward/backwards using her hands on the left side and then on the right side to see if there was any binding and to see if the couplers showed any slipping and they did not show anything wrong.
But so very oddly she was asked to remove the motor connection to the driver and do that test and when she did it there was power backfeeding into the controller. Thatās impossible when the motor is disconnected so something wasnāt rightā¦
Maybe the drivers are marked wrong or something because thereās no way a disconnected motor can backfeed power into anything.
Try resisting the turning of the stepper motor. Can you recreate the stuttering behavior you saw earlier?
If not, it could be your motor has failed at the fringes of required torque. Or thereās a mechanical failure downstream from the stepper. You should be able to follow the chain of motion from the motor to pinion gear, to belt, to gantry to identify at what point the chain is failing/skipping.
If you canāt get the stepper to fail by resisting motion Iād suggest remounting the stepper and checking for the chain of motion starting from the stepper.
That is odd but easy enough to check. Remove Y connector entirely from controller. Then check if a current is being induced with front-back motion. Then remove X connector and retest.
see the video attached it does not spin round as per the tape I attached when powered up, sorry itās late here and my brain is fried 
Well thatās not a good sign IMO because thereās nothing in those things to wear out but the bearings and with no load on the motor it should have no problem turning. I suppose a winding could have burned out but they are NEMA 23 and the drivers are set to 3.5A.
How the X axis started doing the same thing and then fixed itself is also very odd and I personally would want to validate the 24VDC is steady and sufficient. Itās the only thing in common with both drivers and motors but for the Ruida Controller.
If you had a MultiMeter you could measure the resistance of the 2 coils of wire in the motor AND you could measure and monitor the 24VDC power supply. If both coils in the motor measure similarly then the problem is likely elsewhere.
Well the good news it that youāve definitely narrowed the issue down to somewhere from the stepper motor or upstream. That rules out any mechanical issues.
Apologize if I ask something thatās already been done before as itās lengthy thread and some parts hard to follow as it looks like you may have had to remove some videos.
To me it seems that the validations done so far have removed the stepper drivers as the issue. However, it wasnāt clear to me if checks were done to confirm that the cables/connectors werenāt the issue.
Can you confirm if a test with the output of the X stepper driver to Y motor was ever conducted? If so, what were the results when jogging X controls? Was there stuttering on Y motor? If so, that means the issue is south of the stepper driver. Either on the connector, cable, or stepper motor. In that case Iād suggest take a close look at the connector and make sure all wires are well seated and making a good electrical connection to the connector. Youāll likely need to do this anyway when you get the replacement motor so might as well get familiar with this. Carefully inspect the connector and make sure thereās no damage to the connector and that when connected to the driver that everything is seating well.
Yes I have asked my partner about getting one as we do not currently have one to check.
Yes I had to because my account got temporarily suspended due to high traffic, so I had to delete some of the older videos above to try to help for when my link came back live.
I had initially changed every wire from the X-axis and swapped them over with every wire from the Y-axis. The X-axis was still fine and would move correctly with the controls and the Y-axis was still grinding so there was no change with that test.
I then changed only the motor driver outputs over and the resulting video I had to delete but the results are as follows when powered up and it was trying to home there was a buzzing sound along with the grinding which was not present in previous test.
When I pressed either the left or right directional arrow on the control there was no movement only the grinding, when I pressed the down arrow the laser moved left, when I pressed the up arrow the laser moved right.
Yes I did ask support email how common are those to break as considering this laser is only 6 weeks old when this Y-axis fault started and they said "This is an uncommon quality issue, and we will forward it to our tech team for further investigation and improvement.ā
I have been right round every wire on this laser on multiple occasions and they are all seated firmly with a strong connection
Okay. This test to me indicates that the drivers are likely not bad.
Okay. Then this definitely isolates the issues to something south of the driver. So connector, cable, or motor.
Very nice.
The diagnosis seems reasonable given the evidence. Itās a little hard to accept given that these motors tend to be pretty robust with issues much more common elsewhere. I think itās possible that one of the wires has broken internally along the cable length. You could potentially test for this if you get a meter if you were so inclined.
In any case, I think Dougās suggestion of checking 24V from the supply is a good idea to make sure thatās not somehow damaging the motors. Iād think it would damage the driver first but you never know.
Iām also suspicious of the current configuration of the driver. Yours looks like itās set to 3.5A. I canāt find a specification sheet or much at all on your particular motor to confirm if youāre within spec. While such motors exist theyāre used infrequently enough where Iād want confirmation that itās within spec. Iād suggest checking the replacement motor in case itās a different model.
I did run into a user on Reddit while checking for your motor that apparently must have had a similar failure to you so I guess the issue is not without precedent.
Iām guessing she might as well change out the motorā¦
@onthecakefront ā¦ I know youāre having a hard time with the learning curve, everybody does.
Itās say OMTech doesnāt have any English speaking people to take phone calls for support issues. Itās a drag dealing with a 24hr turn around time in an email.
I donāt think Iām ever going to get this replacement motor so I think I will just go ahead and purchase one if I can get hold of one in the UK.
With the laser now being out of action for so long I canāt really afford for it to be down much longer. As Iām having to cancel orders and I canāt take new orders on either.
They said it would take 5-9 days as they had to order it in first before it would be shipped to me 
As a suggestionā¦ Iād buy a new motor and motor driver. One of them is not operating correctlyā¦
I only say this because in a business, if the machine isnāt working itās costing you money.
Both of these are relatively low cost. I think the last motor diver I purchased was around $20 US. Cheap insurance ā¦
If you use these machines much youāll have a box of āspare partsā anyway, just like the rest of usā¦ 
Donāt know how many times, what I needed at the moment, was in the ājunk boxā.
Good luck
I had OmTech send me a replacement connector. No emails it just showed up.
I have been trying to find a new motor but with not much luck in the UK theyāre not easy to come by. I am still investigating and searching as I want to make sure I get the right one
I hope mine shows up as I have tried searching for the numbers on the side of the motor and google just throws up a blank 
So iām no further forward at the moment.
What type of motor is it?
These are NEMA based, a NEM17 it 1.7" on each side ā¦ a NEMA23 is 2.3" on each sideā¦
Itās got 4 wires, so itās a two phase stepperā¦ These mounts are standard as is the motorsā¦ It should be a simple swap out for a new motor of the same size.
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Are you looking strictly for local shops where you can talk with someone? If so, try looking for things like āautomation systems supplierā āmotion control supplierā or āCNC tools supplierā in Google Maps for things near you. Electronics hobby shops might have it or could help you identify who would.
If youāre looking for somewhere in-country but not necessarily local a search for āUK stepper motor supplierā brings up a selection of industrial suppliers, electronics suppliers, motion control specialists, and hobbyist sites.
I had the same experience when checking that part number. The main things youād be looking for:
- Itās almost certain that the motor is a NEMA 23. This defines basically dictates the size of the faceplate and the location of the mounting holes. NEMA 23 should be roughly 2.3 inches square at the face. The mounting holes will be 47mm apart center to center. Measure yours to confirm.
- You will need a dual-shaft model
- Shaft diameter, shape, and overall length will be important to couple with your existing setup.
- Will be easiest to stick to a 4-wire bipolar motor for wiring simplicity
- Look for one rated to 3.5A or slightly higher as that is how your driver is setup.
If you talk to someone at the shop they should be able to confirm fit for purpose and swap-in replaceability.
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Thank you for your detailed explanations they really helped 
Iāve gone for this one as itās the closest I could find to my measurements I couldnāt find one with any higher amps
Nema23 Dual Shaft 8mm 6.35mm Stepper Motor 56.4x56.4x56mm 1.3Nm 3A
This hybrid bipolar Nema 23 stepper motor with 1.8 degree step angle (200 steps/revolution).
Double Shaft Nema23 Stepper Motor (23HD4404-25S)
Specifications:
Motor Depth: 56mm Phase: Two phase 4 lead wires bipolar stepper Step Angle: 1.8 degree Rated Current: 3A Rated Voltage: 3.3V Holding Torque: 1.3N.m Dual Shaft: Front 8mm Flat 18mm and Total Length 25mm, Rear 6.35mm Flat 15mm and Total Length 20mm Black n Green, Red n Blue are phase A n A-, B n B-
Will see if this motor driver does the trick to at least get me going again.
I have a long list of things just to get in as spares so I reckon I will need a bigger box
It will be good just to get over this initial set back and then get going again.
That motor has a rear shaft of only 6mm, yours is 8 both ends? so youāll need a 6-8mm reduction sleeve.
The 4-wire version of this would be a very close fit:
Thank you I have been trying for the last few days to find one in the UK with those specs and I have asked a few places over here. One place had one that was similar but they did not seem confident that it would be what I needed so iām still searching.