x-axis going out of level

I am currently facing an issue during printing where the x-axis goes out of level after a while i.e. measuring the distance from the bottom of the X axis smooth rod and the top surface of the Y axis aluminum bed plate. I noticed while printing halfway, the left z-axis motor stopped moving while the right z-axis motor continued to move and the x-axis went extremely out of level of about more than 1cm. This flattened the z-axis of the print basically as the left side was not able to move.

I did some troubleshooting and realised the left motor turns with more resistance than the right motor and suspected too much friction in the left threaded rod at the top and bottom bearings. I oiled the parts and the threaded rod rod turned a bit better this time. Thereafter I ran cura and did increments of 0.1mm to simulate a print going on and realised after doing like 20 to 30 times the x-axis still goes off by about 1-2mm after leveling it.

Any ideas on how to fix this or suggestions as to what is going on? Thanks!

Check the motor coupler set screws on whichever motor isn’t turning, it can sometimes come loose and then turn, but not actually engage the leadscrew on one side. Also check for loose connections.

if it ins’t that, it could be that you just don’t have the X axis paralelle at start. If it is off even a few threads, the excess friction binds and then causes one side to stick. In your case, I would start by removing the X axis belt, carriage and smooth rods and then make sure each individual X axis end assembly runs up and down the leadscrew smoothly without binding. Then home the Z axis and reset both leadscrews so that the distance from the top of the lower motor leadscrew support bearing to the bottom of the Z nut itself is identical on both sides. Then reinstall the X carriage rods, and belt and try it again.

If it’s binding, something is loose or off.

So I tried and checked the couplers, managed to reseat two of the set screws and put them back in but was unable to remove two. Same thing happened. I did some troubleshooting and realised if the left motor were to be elevated 5mm higher than the right side, the thread turns easily. However, when both are level it is harder to turn on the left motor. Not sure if this is expected for the Taz. Also, I realised when the left motor stops moving, the axle of the stepper motor also stops moving, thus it cannot be cos of loose set screws. The motor just vibrates only.

So I tried the same 0.1mm inching with the left motor axis elevated 5mm higher and the rods remain easy to spin and it doesn’t jam. However, when the x-axis is level for both, the left motor will jam after a while(0.1mm inching) with the threaded rod being extremely difficult to turn manually.

Just to follow up on this:

I dissasembled the entire x-axis and followed your instructions for checking if the x-axis wasn’t level but that didn’t help after I disassembling and re-assembling few times. After further troubleshooting I realised it was caused by the misalignment that happens when the bolts securing the x-axis supports to the z-nuts are tightened. I took all the bolts out from the z-nut and put them in one by one, testing the rotation of the z-axis as I went. Eventually I realised some bolts cause the jam whilst others were fine. In the end I had about 2-3 bolts out of 8 removed per side to alleviate the jamming.

After I did all that, the printer is now printing like a charm, haven’t failed yet in any prints Ive done thus far.

I am not certain of the cause to this problem but I have given feedback to support and hopefully this is checked as part of the QC process too cos I wasted couple of days troubleshooting the whole thing.

if you have time can you try something for me. put in all the bolts. Loosen the set screws that hold the x-axis 10mm smooth rods in place. Really just one side needs to be loosened. Run your test and see if it binds. I had the same issue and could never get it right. After replacing the leadscrews with ballscrews I noticed my frame seemed to be misaligned, i.e. the corners were not 90 degrees. I think that was causing tension on the horizontal rods, jaming one side. I made sure all the corners were square, ran the Z axis up and down with the rods loose, then tightened them. You can also introduce tension if the belt is too tight I think.

When I rebuild my TAZ I may try a horizontal x-carriage to eliminate any potential alignment issues because all the weight will be centered on the 16mm ballscrews.

I did finally get good prints again before my TAZ turned into a TAZ torch :slight_smile:

The ao-10x series (taz precursor) had horizontal rods. Vertical is less prone to carriage droop and x offset wobble. I converted my ao-10x to vertical and it did improve things so I would recommend sticking with a vertical alignment. Since you are looking at a rebuild anyways, you might want to check out the openbuilds extrusion projects in the development forum.

What printers are the people in this post talking about? TAZ 4, 5 or something else.
Also is there a diagram that shows all the parts these people are talking about, I think I know what he is talking about but a diagram would help.
“bolts securing the x-axis supports to the z-nuts are tightened. I took all the bolts out from the z-nut and put them in one by one, testing the rotation of the z-axis as I went”