Problems with Z-axis Movement for A5

jspinelli73

I am having an issue with my Z-axis movement.  When I manually move the Z-axis up and down using the buttons, or when a print is occurring, the left side of the printer doesn't seem to move every step with the right side.  The left side seems as if it is getting caught and does not move evenly, thus causing the gantry to become not level.  Even if i manually re-level the gantry by rotating the threaded rod, it will become un-level again when the Z-axis moves with the motor.  What do you think the problem is?  Is there recommended maintenance or is there a part that needs to be replaced?  I attempted to fix the problem by removing all of the lubricant from that side and re-lubricating the threaded rod.

I have also not installed new firmware since December 2018, if that is relevant information to the problem.  This problem began occurring towards the end of May, and the printer was functioning smoothly from December to May.  I also have not done much maintenance until this point.

Thank you

ThingsNSchtuff

I had a similar issue with my printer. The things i did to fix it are as follows:

1.  Loosen the couplers on the threaded rods and make sure they are both seated all the way and securely tighten the couplers.
2. Make sure the entire printer is level using shims. (X, Y, and Z axis should be leveled as accurately as you can get them) Have yourself a bubble level with rounded slots in it to make this easy for later. (this is mainly in preparation for the next step)
3. After you are 100% positive its level, slide your print head all the way to one side or the other and set the bubble level on the x axis rails.
4. go into the menu for "move" and adjust your increments to your desired amount (.1 mm, 1 mm, 5 mm, 10mm)
5. Depending on which side needs to go up, you will have to apply manual force to the opposite side and raise the z axis. This will adjust any offset in the z axis. 
6. Repeat the last steps on both sides until you are satisfied that the rails are level.

I had to do this after my head got caught on the boden tube and offset the z axis on a couple prints near the top. My main indication that i had a problem was that during bed leveling, my adjustments in the corners were very exaggerated with each corner being wildly off in adjustment from the last. (imagine 5mm difference in each corner)

Also, i suggest just taking that front guard off and leaving it off. It looks nice, but it hinders access to the belt for tensioning and the rails are really what is important for this process.Having access to the rails also enables easier, more frequent, cleaning and lubrication which keeps it quieter and printing well. 

I think for me, the small amount of binding that was happening because of the offset was enough exacerbate the problem over time. Once I did these actions, it cleared up and the issue has only recurred when the bowden tube gets hung up near the top. 

Hope this helps, and good luck. 


As you can see in my pictures, i need to readjust mine a bit to get her where she needs to be, but i think you probably get the gist by now.

jspinelli73

Thank you for the suggestion! I apologize for getting back to you late, however, I just tried this fix last week because of a busy summer.  Unfortunately, I am still having an error and I think it is more of an issue than being un-level.  After this fix, I did some research and found that the motor may not be getting enough current and I adjusted the screw on the z-axis potential meter by a 1/4 turn clockwise.  This also did not fix the problem.  Just now I noticed that the left side (problem side when facing the front of the printer) does not turn in one direction and instead rotates both ways with just one touch of the Z-axis Up move function.  It does the same thing with one touch of the Z-axis down function.  This is demonstrated in the attached video.  Please let me know if there are any other ideas out there! Thanks