This thread’s solution worked for me.
Taz Pro Solution Procedure:
STEP 1: Diagnose the specific unevenness of your 3D printer’s bed. Make sure to clean your nozzle first for accurate Z-probing.
- Taz Pro -> USB Cable -> Computer with Cura Lulzbot Edition
- Cura LE -> Monitor -> Disconnect, Connect, Console
Commands:
- M420 S0 (disable auto leveling)
- G28 (auto home)
- G29 V4 (auto Z probing, full diagnostics)
STEP 2: Add shims under the bed corner standards. Measure Z values and add/remove/adjust shims accordingly.
Shim STL file (0.2mm thick, single layer printing recommended) attached. Print about 10 of these as someone wisely suggested.
Use a 2mm hex key to manipulate the 1 washer-screw and 2 standard-screws per corner.
I did not like how the washers bent at an angle after applying some shims, so I redesigned the shims to have a smaller center-hole (3.5mm) to lift the metal spacer as well- but this was a problem as the washer needs a conductive path to the bed for the Z-probing electrical-sensing. So I reverted the changes and instead replaced the 8 standard-screws with A2 stainless steel M3, 16mm length, philips button head screws. The new screws (bigger heads) helped the washer sit at a more even angle, improving the accuracy of the Z-probing process.
STEP 3: Adjust your printer’s Z-offset then test your bed’s practical evenness by printing a calibration part.
When you add shims to the bed corners, your bed surface height may change. Therefore your printer’s extruder Z-offset may need to be adjusted (usually, raised; for the Taz Pro, raising the extruder = adding the the Z-offset; my z-offset went from -1.4 to over -1.3).
Testing STL file (270mm x 270mm x 1mm, 2mm line width) attached.
EDIT: Realized that the conductive path is maintained by the washer->screw->bed contact. Bed corner shim STL file version 2 reduces the washer mounting angle, hence improving z-probe accuracy. Dimensions of bed corner standard also attached for your reference. Also, for ease of shim adjusting, I replaced the aforementioned 16mm screws with 12mm screws installed in reverse (screwheads are under bed).
bed_corner_shim.pdf (64.6 KB)
bed_corner_shim_v2.stl (43.1 KB)
perimeter_270.stl (15.7 KB)
bed_corner_shim.stl (54.8 KB)