Failing to find correct Z-Offset. First layer tuning frustration
Long story short bought mk2 non assembled unit awhile back assembled without problems first prints went off without a hitch printed a good amount of stuff with no problems nothing crazy but wasnt just a few prints. All of sudden first layers were not sticking and seem liked the bed was super warped. Checked with flat edge and of course it wasnt as flat as machining tools but with the mesh bed leveling I cant imagine that was the problem. Below are some G80/G81 z-outputs let me know if the drift i am seeing between calibrations is normal or is part of the problem. Also if anyone has seen this in the past or have anything I can check I would be greatly appreciative. I am about to take a sledge to it and give up and buy a new one but the fixer in me can not give up until solved.
Recv: 0.10083 0.10796 0.09241 0.05417 -0.00676 -0.09037 -0.19667
Recv: 0.16843 0.19463 0.19775 0.17778 0.13472 0.06858 -0.02065
Recv: 0.21231 0.25401 0.27306 0.26944 0.24318 0.19426 0.12269
Recv: 0.23250 0.28611 0.31833 0.32917 0.31861 0.28667 0.23333
Recv: 0.22898 0.29093 0.33358 0.35694 0.36102 0.34580 0.31130
Recv: 0.20176 0.26846 0.31880 0.35278 0.37040 0.37167 0.35657
Recv: 0.15083 0.21870 0.27398 0.31667 0.34676 0.36426 0.36917
Recv: 0.15000 0.15083 0.13083 0.09000 0.02833 -0.05417 -0.15750
Recv: 0.21500 0.23791 0.23834 0.21630 0.17177 0.10476 0.01528
Recv: 0.25944 0.29970 0.31726 0.31213 0.28430 0.23378 0.16056
Recv: 0.28333 0.33620 0.36759 0.37750 0.36593 0.33287 0.27833
Recv: 0.28667 0.34742 0.38933 0.41241 0.41665 0.40205 0.36861
Recv: 0.26944 0.33334 0.38248 0.41685 0.43646 0.44131 0.43139
Recv: 0.23167 0.29398 0.34704 0.39083 0.42537 0.45065 0.46667
Recv: 0.17667 0.17157 0.14907 0.10917 0.05185 -0.02287 -0.11500
Recv: 0.24213 0.25912 0.25649 0.23426 0.19242 0.13097 0.04991
Recv: 0.28741 0.32199 0.33621 0.33009 0.30362 0.25680 0.18963
Recv: 0.31250 0.36019 0.38824 0.39667 0.38546 0.35463 0.30417
Recv: 0.31741 0.37371 0.41257 0.43398 0.43794 0.42445 0.39352
Recv: 0.30213 0.36257 0.40921 0.44204 0.46106 0.46628 0.45769
Recv: 0.26667 0.32676 0.37815 0.42083 0.45481 0.48009 0.49667
Recv: 0.18333 0.18037 0.16037 0.12333 0.06926 -0.00185 -0.09000
Recv: 0.24759 0.26823 0.26897 0.24981 0.21076 0.15181 0.07296
Recv: 0.29287 0.33172 0.34959 0.34648 0.32240 0.27734 0.21130
Recv: 0.31917 0.37083 0.40222 0.41333 0.40417 0.37472 0.32500
Recv: 0.32648 0.38558 0.42687 0.45037 0.45607 0.44397 0.41407
Recv: 0.31481 0.37595 0.42354 0.45759 0.47811 0.48508 0.47852
Recv: 0.28417 0.34194 0.39222 0.43500 0.47028 0.49806 0.51833
RE: Failing to find correct Z-Offset. First layer tuning frustration
If you let the PINDA measure without temperature compensation you will get run to run variations like this. Unfortunately, I'm finding the PINDA temp compensation provided by Prusa on the MK3 (3.7.1) is not working as expected, either. Unsure if the issue is also present in the most recent MK2 firmware.
RE: Failing to find correct Z-Offset. First layer tuning frustration
I am also wondering if it might not be the hot end that is giving me trouble.
Anyone else have any recommendations for troubleshooting steps
RE: Failing to find correct Z-Offset. First layer tuning frustration
the Mk2 Pinda does not have temperature compensation, and suffers from thermal sensitivity,
I find it best to raise the extruder to say 60mm, before heating the extruder and heatbed, then do Live Z adjustment.
then lift the extruder to about 60mm before doing the next print,
etc.
if you sometimes start with the pinda near the heatbed, and other times start with the Pinda further away from the heatbed you will get differing results all of the time!
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Failing to find correct Z-Offset. First layer tuning frustration
zThanks Joan - didn't catch it was a MK2. Would be nice to see a way to filter "recent" results to certain forums.
RE: Failing to find correct Z-Offset. First layer tuning frustration
1. After a print my printhead goes +50mm up so non influence of the heat of the bed when I start next print:
{if layer_z < max_print_height}G1 Z{z_offset+min(layer_z+50, max_print_height)}{endif} ; Move print head up
2. To eliminate the temperature influence of the PINDA by the warm heatbed (print head/pinda is +50 mm above heatbed) AND the extruder (warm up to 170 and then do meshbedleveling, then warmup to desired temperature) , I changed my start gcode:
M140 S[first_layer_bed_temperature] ; set bed temp
M190 S[first_layer_bed_temperature] ; wait for bed temp
M104 S170 ; set extruder temp op 170
M109 S170 ; wacht op bereiken extruder temp 170
G28 W ; home all without mesh bed level
G80 ; mesh bed leveling
M104 S[first_layer_temperature] ; set extruder temp
M109 S[first_layer_temperature] ; wait for extruder temp
Frans Krau
Europe, Holland, Apeldoorn