X-axis moves only one direction on UM Mingda

[jon-eivind-lygren 0]

After just some days of testing, the X-axis moves only one direction.

I have tried moving the cables from the Y-axis to the X-axis on the motherboard, and the X-moves when using the Y-controls. By other words, the issue is related to the control of the X-axis.

I did read something about replacing an arduino control of some sorts, but also that I had to upload a new firmware by doing so.

As my UM II is not an original one, but a "Mingda" (I needed the larger printer-surface of this model) I am not sure if I can update the firmware with "stock" ones?

I am in contact with Mingda, but they are extremely slow in responding to the matter thus I would like to try to figure this out myself if possible.

Any help would be highly appreciated!!

 

[IRobertI 520]

I'm sorry, but since you're using a clone it will be very hard for us to help since we don't know what parts are in it.

 

[illuminarti 18]

If the motherboard has separate stepper driver boards for each axis, you might check whether the driver for x is defective. You could carefully swap the driver board for the X and Y axes, and see if that transfers the problem. If so, maybe replacing the driver board might help. You should be able to find stepper drivers online.

However, since this is a 3rd-party machine, not officially licensed (and if it's a UM2, then it's totally been re-engineered, since the UM2 plans haven't been open sourced yet) then, as Robert said, it's hard for anyone here to give you specific advice as none of us have any idea how the printer is assembled, or what components were used.

 

[jon-eivind-lygren 0]

Thanks for replying. Not sure what components this machine uses, but the producer mentioned "second generation" thus I was thinking they were referring to the UMII. The machine was delivered with the Ultimaker software (CURA), and the manual specified to select the UMII for slicing...

However, the menus / setup etc etc. is terrible, it won´t even return to "home" after having printed. We also have a Makerbot here, and although the MB is quite basic as well, it´s a supercomputer compared to this one..... Anyhow, the print-surface of 200x300x360 is what made us purchase one of these for testing-purposes.

I guess I would need a new driver for the X-stepper-control. Where are those normally located? I did not see any on the front-section of the motherboard, perhaps I need to loosen the board?

 

[gr5 2,168]

Your printer is more of a Ultimaker Original than a UM2 so I changed the title.

The UM Original has gone through a few "revisions" but Ultimaker doesn't call it a "generation".

There is a "direction" pin on the PCB. Do *not* choose Ultimaker2 in Cura as that will cause all kinds of problems. Choose "ultimaker original" and go to machine settings and adjust the distances. Don't update the firmware with cura because if you do then you will only be able to print 205X205X205mm. If that is too late - no big deal - you can build your own firmware here:

http://marlinbuilder.robotfuzz.com/

Now to your "direction" problem. I recommend you install "pronterface". You can get it here:

http://koti.kapsi.fi/~kliment/printrun/

Connect to your printer with that and you can then do small (10mm) moves with the x axis. There is a direction pin "dir" on the pcb. That signal might have a bad solder joint. Or it could be defective in the arduino output. Or you could have a defective driver (easiest to test because you can swap 2 drivers).

Here is piece of the schematic showing the "dir" pin:

 

[jon-eivind-lygren 0]

Thanks gr5! This issue occured when I was moving the X-axis too far and thus "stuttered" the motor / driver. As the motor works fine when I am moving the drivers from Y to X, I am guessing it is the driver, not a soldering joint...?

Would I need to update the firmware if I replace the driver? Anyone know how to figure out what driver I need to replace?

Thanks again!!!

 

[gr5 2,168]

The drivers should be clearly labelled and they pop off. The X driver is the closest to the X connector and so on. You can swap two.

I'd like to see a video of what you are talking about. Bur from your words only - I think what you are saying is that the print head is fine until it hits and endstop and then tries to keep going. I don't know about the mingda but the normal UM is tough and it can handle this but it makes a horrible noise and shakes something awful.

The cause of this is usually that the endstop isn't working. There should be 6 endstop switches. 2 on each axis. Really you only need 3 as the other 3 are done in software anyway.

You can test them with power off - push the print head around and you should hear the click as it hits each endstop. If the noisy spot has no click then you can slide the endstop closer in so that it clicks before the axis gets to it's end.

Alternatively the switch could be broken or it might not be plugged in at all.

Or it could be, again, that the direction signal is broken and the axis ALWAYS goes the same direction. This indicates that the DIR signal is an open connection so the driver always interprets the signal to go the same direction. This is what I thought you said the problem is in the first place.

 

[gr5 2,168]

Again, if the problem is that the X axis only goes one direction I would put a meter on the DIR pin and see if it goes from 5V in one direction to 0V in the other. If it is always at 5V or always at 0V then the problem is usually a bad solder joint. Or a bad arduino.