jeffsjunior

I was looking for a place to report a bug, but I couldn't find anywhere so I created a topic. If that is wrong, tell me where to post. Everytime I update Cura I also update the firmware of my printer, the last one I used was the Cura 3.4 and the firmware was alright on my UMO+ printer. Today I updated to the new cura (Cura 3.6) and when I uploaded the firmware for my UMO+, it stopped working and became unresponsive. Then, I reinstalled the old Cura 15... and now it works again. Just to make sure it wasn't a bug, I uploaded the firmware again from Cura 3.6 and the same problem happened. In conclusion, right now I am using the firmware from the older cura because the new one is problematic.

It is not the heat for sure because here where I live, it is really hot ( brazil ), so I always use it with a fan blowing air underneath the printer (ahahahha). Update: After removing the Z axis and cleaning it very carefully with a toothbrush and an old T-shirt, I tested the linear bearings without the Z axis and it seems that the problem is the linear bearings. I can feel a spot where the bearings resist, just a little bit, to move near the height where I have the problem. I rotated the linear bearings, just to see if it would get better, cleaned the rods (again) and carefully tightened the screws one by one while I was moving the bed up and down (again). Now it feels a little bit smoother, after greasing the Z axis again, I will try a few prints to check if the problem is gone "forever". If it is not gone, I think I will have to buy/ask ultimaker new linear berings or new rods, or both, I don't know ahahaha.

Maaan, so many variables to analyze. I cleaned the Z axis with a toothbrush, i didnt remove it, just brushed it a little bit at the height that I am having the problem, and the print was awesome. However, I also printed it over USB, and downgraded the firmware to CURA 15.04.03 because when I updated to the CURA 15.04.06 the "scar" got worse and became a fully missing layer. When I stop to think, it just seems a coincidence, I don't think the firmware or the SD card has anything to do with the problem, but it costs nothing to ask, so I am asking. Do you all think it might be the firmware or the sd card? or everything together?

This is such an awesome tip, thanks

while I dont buy the WD40 to clean it properly, I decided to use a toothpick to reach the difficult corners of the Z-axis to remove some of the old and dirty grease that was attached there, and it solved the problem for one print, but it came back again a little bit better than begore. Theferore, it is dirty grease for sure . Do you have and advice how to clean it properly? reaching all the hard spots to clean? I just used a soft cloth and it didn't help much. Thank you

Thanks for the reply. I bought it last year, but it is still in the warranty. Since this only happens at only 2 specific spots, I guess the problem is with the Z axis This is kind of a new issue, I left it stopped for 3 moths, I guess, (covered) and this problem happened. I will try loosening the screws ( never tried this) and check if I can fix it by cleaning specific spots. Thank you

I am having this weird problem that at almost all prints 2 horizontal lines appear. I printed a tower with 0.2mm layer height and the lines did not show up, however, as you can see in the picture the other 3 prints had the same problem almost at the same height. I say "almost" because other prints have those lines a little bit above or below the ones you can see in the picture. It seems that the Z stage cannot move one layer so it adds another layer at the same height and then it skips one layer, but it does not explain the double horizontal lines, so I am not sure if this is the problem. I removed the Z axis and cleaned as much as I could, but it did not solve the problem. I still can see 2 horizontal lines. Soooo, does anyone have a good idea how to fix that?