X-Axis motor jumping around

[TheDreamMaster]

Some more information:

1. Once the motor starts violently moving and I stop the print, if I try to move the motor using the manual controls (1mm), it still moves violently. When it moves with the manual control, it makes a loud noise and moves in a BIG STEP instead of 1mm. It jerks fast and shakes the whole printer.

2. Pressing Autohome makes the Y and Z axis move normally, but the X still moves super fast and hits the end-stop hard.

3. Sometimes adjusting the pot on the motor driver will fix it, and sometimes it will not. The driver is NOT HOT OR WARM and the CARRIAGE IS FREE TO MOVE easily, so it does not seem like either overheating or a mechanical problem.

I am suspecting a problem with the motherboard because all I have tried has not worked.

[Mark]

"each step is multiplied by 10"
How about the subdivision of the X motor?

[TheDreamMaster]

"each step is multiplied by 10"
How about the subdivision of the X motor?

I am just estimating by how it looks when it moves.

Do you mean the microstep resolution?

It has to be ok, since the motor does work well when it is working. The problem is that it randomly starts jumping around. If it was a software problem, it would have to be a consistent behavior, either good or bad. What we have here is a random problem.

When I manage to fix it for a little bit, the motor moves perfectly both manually and while printing, but all of the sudden it starts moving wildly again. It takes lots of time and some luck to be able to make it move properly again. I adjust the driver pot both up and down and at some point the motor works fine again.

I really do not understand why this happens because the current draw depends on the motor load, so setting a higher current limit should not make the motor move more. Motion is controlled by the pulses sent by the microcontroller. So I don't see the relation between the pot adjustment and the wild motion on the motor.

Could it be that a faulty microcontroller board is sending false pulses to the stepper motor?

[Mark]

I think you can test it like this:
swap the X axis motor with the Y axis one(swap the motor not just motor wires), if the Y axis(motor X) is jumping around, then motor X is defective, not the bed.

[eyals]

Looks like I'm having EXACTLY the same problem, mine on the Y axis.
Controlling it manually cause a hum + incorrect movement.
Trying to print something makes it run like crazy from side to side.

Replacing the motor to a new one, didn't make any change.
Replacing the X axis motor cable with the Y axis cables moves the problem to the X motor - meaning it is not the motor or cables.

Any idea? or should i replace the GT2560 board?

BTW, this is really piece of crap. one of the extruders, was not working (ever). I purchased an dual extruder kit (this is why i had another spare motor...). a few days after I installed the printer, the power supply stopped working. now the board????

[Mark]

"Replacing the X axis motor cable with the Y axis cables moves the problem to the X motor - meaning it is not the motor or cables."
You mean you just replace the cable ? if so it's the problem of the cable I think.
If you replace both the cable and motor with the Y axis(that means plug the X axis calbe into the Y slot on the board), and it happened to the X axis, then you should check the Y motor driver, check the voltage or swap it with the X axis one, see if the driver dead or not.

[karateguy12]

Has this been resolved? If so please post the resolution so that others can benefit. Thank you.

[TheDreamMaster]

"Replacing the X axis motor cable with the Y axis cables moves the problem to the X motor - meaning it is not the motor or cables."
You mean you just replace the cable ? if so it's the problem of the cable I think.
If you replace both the cable and motor with the Y axis(that means plug the X axis calbe into the Y slot on the board), and it happened to the X axis, then you should check the Y motor driver, check the voltage or swap it with the X axis one, see if the driver dead or not.

This is a reply to another guy that seems to be having the same problem. But just in case someone is getting confused...

In MY CASE, I have changed the motor AND cable. When I switch to the motor AND cable the problem transfers to the motor I changed to. So it is NOT THE CABLES. IT IS THE SIGNAL COMING FROM THE DRIVER. I HAVE NOT SOLVED THE PROBLEM. As I said before, I have checked the voltages (all my drivers read around 0.8V), I have adjusted the voltage, changed the driver for a new one, and still the problem persists.

I am pretty sure the problem is the board. I can't speak for someone else, but I would not be surprised if this is a recurring problem with other owners.