Cura 2.6.52 Y Axis Misaligned on the Mini


I attempted to print a ring on my mini with a 5.75in diameter with the new Cura software version 2.6.52. When it started to print the diameter fell off the back of the print bed.

I do not have “Machine Center is Zero” checked in Machine Settings.
I do have the Mini and the Taz 6 set as my printers (Taz 6 is in transit). The Mini is the Active profile.

Startup tests pass, touches all 4 washers for the self leveling. That proves the software knows the machine is in fact a Mini.
I’ve never had a problem printing anything else, then again I’ve never printed anything so close to the bed’s limitations.

I printed the same .stl file using the old Cura 21.08 software. It printed within the boundaries.

I suspect a bug with this new software.

Hello Joe,

We attempted to duplicate the issue in house, and didn’t run into any issues. These are 152 x 152 circles:
IMG_20171128_075424.jpg
IMG_20171128_074558.jpg
Have you verified you Y axis pulley has both set screws secure, with one on the flat of the motor shaft? Tight y axis belt?

I also notice in the photo, you are missing the wiping pad on the rear of the plate. Have you made any custom modifications to the printer or tool head?

I have not verified the set screws on the Y axis, I will do so tonight; however, it printed flawlessly with the older Cura software.

The wiper is missing cause the first attempt ran it over and got PLA plastic all melted on top of the felt, I removed it to replace the felt, then I thought that’d be a great time to take a picture of this error without having the head run into the wiper assembly. This also proved it wasn’t a one time fluke and that I can do it repeatedly.

When you duplicated this did you have the Mini and Taz 6 printer profiles installed with the Mini as the Active profile?

Indeed, I have the TAZ 6 added as well with the Mini selected.

Cura LulzBot Edition has a little bit more advanced controls, and different profiles (they did not copy over well.) A difference in acceleration and/or jerk from the change could cause a faster Y axis movement than Cura original. This could cause a skip if your screws were just slightly loose as opposed to tight.

If anyone else out there would like to give it a shot, you can find the STL file below. (Note you will need to disable all skirt settings in order to print to max volume.)
test_mini_x_y_voluume.stl (52.9 KB)
Let us know what you find out with that set screw!

I am also having the same problem with my Mini

Okay I think I’ve discovered the problem. I think I had skirt selected. I started a print on your file and it made it all the way around 360 degrees (I hade to scale it back to 97% to get it to work). I started a print on my file without skirt selected and it made it all the way around. Both prints were still a little bit off (closer to the back side than the front side, left and right sides looked even). I then selected skirt, it started up top in about the correct place, made it about 3/4s the way around (assume 250mm of filament) and then it just shifted over to the right and started to print way below where it should’ve started. The path looked to be the same as what I posted, it was on a collision course with the wiper, I cut the power to prevent damage.

It is worth mentioning that I did indeed print a 250mm skirt with the older 21.08 Cura software. My file was slight smaller than yours.
I don’t know why I can’t fit 152mm x 152mm file on the platform. My printer settings are set to 155 x 155 x 158. See attachment. I did select the model, right clicked and selected “Center on Platform”. As I mentioned, I had to scale yours down to 97% before it would work for me.

The software is a little bit buggy. The developers should test laying down a skirt with a smaller file and see where the print begins; I can foresee moving my model down to the lower end of the bed for a print (to avoid the center hotspot to prevent elephant footing) and letting the printer print a skirt to get the filament flowing and then it beginning to print to low on the bed and falling off like it did with these ring models.

Regards,

Joe,

Thanks for the detailed feedback! It has popped up another issue =) The max build volume of the Mini is 152 x 152 x 158. We currently have it set to 155 x 155 x 158 in the machine settings. This will explain why it was about to hit your wiper pad with your skirt. (ticket submitted)

The model will need to be scaled to 97%, or you need to disable skirt. Skirt takes up an area of your overall print volume, and will need to be disabled to reach the full build volume. The 152 x 152 model has a skirt that takes up an extra 6mm in x and y (3mm on each side)