Uneven first layer
Hi all,
I have a Prusa MK3S+ that’s about 10 months old now and I have been struggling to get an even first layer print. I have tried almost everything including:
1. Repositioning pinda and recalibrating
2. Testing pinda with metal knife
3. Tightening screws on the XZ axis assembly
4. Nyloc mod on the print bed and calibrating with pronterface to get within .01 mm across the bed
5. Replacing the nozzle (standard brass .4mm, purchased from prusa, not aftermarket)
6. More 3x3 calibration prints than I can count
After several months of struggling to get things level I’ve finally decide to post here as I am at a loss for what else to try. I’m currently using:
Firmware: 3.13.1
Z-offset: -0.950
Bed level correction
left side: +60 um
right side: +75 um
front side: +10 um
rear side: +10 um
My problem seems to be predominantly along the horizontal axis, here’s a pic of a 1-layer rectangle I printed that shows the issue:
As you can see, portions on the left and right are the correct height but in the middle the nozzle is too high, yet the height is not even across either dimension. I have tried both 3x3 and 7x7 leveling, neither fix the issue. I thought I might have a bad pinda but I don’t want to spend $30 on a new one only to have it not fix the issue.
Any help anyone can offer would be much appreciated. I’m growing extremely frustrated with this issue as I’ve been fighting it for several months. I paid more for a prusa specifically NOT to have issues like this. Every step of the way it feels like the auto-leveling is not doing it’s job at best, and fighting me at worst. Any help anyone can provide would be much appreciated. Thanks.
RE: Uneven first layer
If you have a bad Pinda, you won't be able to run the xyz calibration. I fought with a poor one, that failed on one point of the XYZ calibration until I got a new PINDA.
Someone with more experience than me may be able to answer the Z-cal question better. I have never had the full print like that at the same level but have not had issues with printing large parts. There is a procedure to get your bed leveled better. I have not done it yet.
What is the thickness differences across the print?
RE: Uneven first layer
Thanks for the reply, that's really good to know that a bad PINDA results in failed XYZ calibration. My XYZ calibration completes without error however afterwards the z-offset needs to be adjusted to -1.6 or -1.7 mm to get the first layer to stick. If I raise the PINDA so that the z-offset is -.8 or -.9 (which I read in another post may help with getting an even first layer) the nozzle will hit the print bed during the XYZ calibration. What I did to compensate was run the XYZ calibration with the PINDA adjusted so the nozzle just barely doesn't touch the bed. then afterwards turn the PINDA 1/2 rotation anti-clockwise to reduce the z-offset.
The print in the picture is just a single layer the whole way across. After running pronterface G80/G81 and adjusting screws to get the bed measuring completely level with the PINDA in 7x7, I was surprised that I still needed to use bed level correction to adjust all 4 sides which is why I initially suspected the PINDA. Its almost like my print bed is convex or something. I have not played around with the extrusion settings, but I might try adjusting the screw on the extruder and taking the spool out of my spool enclosure to make sure its being fed smoothly.
RE: Uneven first layer
Have you washed the steel sheet with washing up liquid (Dish Soap) and warm water? That should sort out any adhesion issues. I had terrible trouble getting the first layer nice and once I washed the steel sheet it worked like a charm. After washing and drying it, wipe it over with 99% IPA.
RE: Uneven first layer
Yup, I washed with dish soap, dried, then used 99% IPA to wipe down. I also tried using a lint-free cloth and compressed air to clean any particles off the bottom of the sheet and print bed to ensure it wasn't some particles causing unevenness.