Print position different from Slicer
I've been printing on my recently upgraded MK4 printer without any issues. I was printing this one item from Printables, following the directions on it which said to print it at 0.3 layer height I changed the print settings in the PrusaSlicer to the "0.30mm DRAFT @MK4 0.4" option. The first image below is how the slicer was showing the item positioned. But when it started printing it seemed like it was all shifted over to the right. In fact the head actually seemed to hit against the right side X stop. And for some reason it did something like 49 calibration points instead of the normal 15 points.
You can see in the second image as it was doing the outer edge of the print, it had actually shifted a small amount. In the third image you can see how far over it's printing the item and the right edge of the printing is right on the very edge of the print sheet (and my print sheet is mounted evenly on the heatbed).
So I was wondering if anyone knows why it shifted so far to the right for this printing? Did changing it to the 0.30mm DRAFT have anything to do with it? And why did it do the 49 (or so) calibration points instead of the normal 15?
Best Answer by JMHaro:
I think I finally figured out what happened. I have a modified heat bed cover on the back of mine to allow my heat bed to travel the full distance within my Lack table enclosure. When I did the upgrade from my MK3 I kept the same cover on it but I went ahead and used the filament guide inside of the cloth sleeve which kind of holds the harness upwards (as shown in my first picture above). I just now tried to print something else that uses about the full print area. During the initial bed leveling it does, the hot end harness is hitting against the heat bed harness causing it to stutter and not reach the full left side of the print area. So that's what caused my printing to move over to the right.
So now I just need to come up with a different way to run the heat bed harness but still allow the heat bed to have full travel.
RE: Print position different from Slicer
I can't see how this could have possibly anything to do with the print profile.
There's no "normal" 15 for the Mk4 or XL. The number of spots probed is determined by the size of the object.
Why did it shift? Did you try to print it again, with same result? Could be a corrupted gcode file but I've never seen one myself in all those years. Looks like it did okay at the beginning so maybe this is just a good old layer shift. Could be caused by a slipping belt, or loose grub screws on the motor shafts. Or the nozzle hitting infill or curling overhangs. You didn't specify what material you were being. With PETG I wouldn't be surprised to see some curling with honeycomb pattern like this.
But my first step of troubleshooting would be to print it again.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Print position different from Slicer
Thank you, I didn't know about the number of probed spots, so that explains that.
I decided to let it print which it just now finished. Even though it's at the very edge it seemed to have completed it OK. I've never seen something print that far off from what the slicer was showing. But, I've only been printing usually smaller items so I've never paid attention to know if they were printing in the same area as the slicer was putting them.
I was printing with PLA for this item. I'll try slicing it one more time and see if it still does it.
RE:
At the start of printing, does the X-axis carriage even reach the left motor bracket as far as it will go and click against this bracket? Doesn't it just stop somewhere nearby? Is there something sticking out of the left side of the X cart? Are the bearings on the X-axis lower rod properly installed and does the bearing stick out? This looks like an offset X axis zero position. I would try running an XY calibration.
RE:
At the start of printing, does the X-axis carriage even reach the left motor bracket as far as it will go and click against this bracket? ...
It does go all the way to the left motor bracket. It does what appears to be the initial home positioning of the X-axis carriage and the Y-axis. I did print something else small and it printed dead center on the plate, exactly where it was shown in the slicer. I haven't yet tried to reslice and reprint this same big one yet, plan on doing it soon, just work has been keeping me busy. Will get to it soon.
RE: Print position different from Slicer
I think I finally figured out what happened. I have a modified heat bed cover on the back of mine to allow my heat bed to travel the full distance within my Lack table enclosure. When I did the upgrade from my MK3 I kept the same cover on it but I went ahead and used the filament guide inside of the cloth sleeve which kind of holds the harness upwards (as shown in my first picture above). I just now tried to print something else that uses about the full print area. During the initial bed leveling it does, the hot end harness is hitting against the heat bed harness causing it to stutter and not reach the full left side of the print area. So that's what caused my printing to move over to the right.
So now I just need to come up with a different way to run the heat bed harness but still allow the heat bed to have full travel.
RE: Print position different from Slicer
Try this
https://www.printables.com/model/536937-prusa-i3-mk4-heatbed-cable-cover-60-degree-60deg-f
I use it for my Mk4s and LACKs.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE:
Try this
Thank you, I will give this a try. I was wondering if this would still have the collision with the x-axis cables, but then I saw your optional pieces, so that looks good.
RE: Print position different from Slicer
It's not my design but it works for me. I first tried it without the extra pieces but it's much better than without.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...