Y motors no longer work in a Synchronized manner

[1984chris]

Hey fellas/gals I realize it's the weekend, not sure if I will get a responce until Monday but I was wondering why my y motors would no longer work in a Synchronized manor. They were all fine for the last few weeks until now? Any apparent reason. As to why?

[Bruce]

First I'd check the mechanical things. Make sure the coupler set screws are tight on the lead screw and motor shafts. Make sure there is nothing stuck in the anti-backlash nut on the Y axis lead screw causing any binding. (Small sliver of wood or metal, etc.)

[Derek the Admin]

Bruce makes good points. You can also mark the motor shaft, coupler, and lead screw with a permanent marker. do that on each side. An 8mm jog should move it 360 degrees, and all three marks should still line up. If they don't line up there is slippage. If they do but it doesn't rotate 360 then there is either binding or something like a stepper driver issue.

[1984chris]

Ok so I did Bruce's check list, every thing is tight on the ball screw to motor connections.
Did Derek's idea, the indicator lines only lined on y motor. So I swaped the a to y same results is now in the y. Thinking I would have opposite results but I didnt,
Wanted to mention the motor that lags revolution makes a knocking sound.
So next I took the x plug in to test both y stepper drivers and a stepper drivers, had consistent results both a and y will revolve the the x 360 deg.
Can only think it's the motor,
I havent cut any thing yet. But have ran a lot of dry runs to get the hang of homing and c.a.m to avoid destroying bits. Lol
What's your thoughts?

[Bruce]

Sounds like the jumper settings on the CNC Shield are off. Check page 28 of the Carve King manual for the correct settings. Make sure the jumpers are seated properly on the pins.
Check the holding torque of the suspect motor. When the motor is turned on but stopped, you should not be able to turn the lead screw with your fingers. ( or be very difficult to turn)

[1984chris]

Hey Bruce! So I had a chance to refer back to page 28. They jumpers are definitely right.
Keep in mind I've had a few successful dry runs. And the motor is definitely got power and difficult to turn.
So now I isolated the suspect motor and individually plugged it into all stepper drive prongs and will get knocking on all the motor plug ins. No other motor has this problem.
I am certain it's the motor at this point.
Has any body heard of one of these nema 17 motors burn out, or give issues this early in action. I've only had it operate 2-3 hours max.
Also all the stepper driver trim screws are reading the .64 to .67 max, like to think they are not the culprit.
If so how can I go about purchasing another motor?
Thanks everybody

[Derek the Admin]

Did I understand it correctly that the lines on the motor, coupler, and screw weren't line up on one side? That would indicate slippage.

[1984chris]

Yes sir! That is correct and I triple checked by actually completly removing the motor and allowing it to spin independently from any coupler.
Set it ont the tabel and watched it struggle to turn 360 with 8mm steps.
Next plugged it in to another driver port that does work same results in all x,y,z, and a its original placement.
Hmmm am I right to think it's the motor?

[Derek the Admin]

If with no load it does it and the issue presents itself as you move it to other working ports, then yes. Please email [e-mail] and reference this thread.

[1984chris]

Ohh shit Derek I ordered the new motors like 15 min ago! I wasn't sure when I would get a responce back. You guys are so prompt and busy I presume. I'll message you at the support with the motors I ordered. Would rather give you guys my money.lol To assure I get it right!
THANKS BRUCE, SEE WHY YOUR THE FORUM GURU.
AND MUCH LOVE DEREK, ADMISTRATOR BAD ASS!

[Derek the Admin]

Thanks Chris!