RepRap Prusa i3 bed auto-level

thingiverse

When going down, the extruder will touch the bed, and the axis will keep on that heigt, since the Z_EndStopMount pieces are not glued to the axis, they will continue going down and the circuit will get opened, then, z-min is triggered. Demo video:https://www.youtube.com/watch?v=AOHPTKWP9wohttp://youtu.be/PSwfhPHeCR4 Download the model:http://www.thingiverse.com/thing:273805 (The Prusa_i3_X_End_Motor.stl is copied fromhttp://www.thingiverse.com/thing:39889/#files) Parts: AutoLevel_Z_EndStopMount.stl x1 LM8UU x1 Screws M3-15mm x1 Screws M3-5mm x1 Screws M2-8mm x2 Nut M3 x1 Nut M5 x1 Just like the "X End motor mount ", Use a M5 nut to pull up/down the end-stop-mount. But need use a M3-5mm screw to fix the M5 nut with it. M3-15mm and the M3 nut is used to grip the LM8UU in the center clamp. Directly use the original Z End-Stop micro switch as the detect switch shows in the figure. Adjust the touch screw of X end motor mount to "just" press the Z End-Stop Switch. When move down Z direction and J-Head hit the bed, X would stop move down, but Z End-Stop Mount wont stop and the micro switch would be released. By this way, Marlin can detect the nozzle already hit the bed. Use Marlin "Bed Auto Leveling, grid mode"https://github.com/ErikZalm/Marlin Edit the configuration.h file.https://github.com/ErikZalm/Marlin/blob/Marlin_v1/Marlin/Configuration.h Invert your Z min end-stop setting. Originally, Z min end-stop is hit when Z at home position, But this design let it release when Z at home. const bool Z_MIN_ENDSTOP_INVERTING = false; Active auto leveling by delete "//" before #define ENABLE_AUTO_BED_LEVELING Update these setting for the rectangle in which to probe #define LEFT_PROBE_BED_POSITION 0 #define RIGHT_PROBE_BED_POSITION 120 #define BACK_PROBE_BED_POSITION 150 #define FRONT_PROBE_BED_POSITION 50 Set the number of grid points per dimension. I wouldn't see a reason to go above 3 (=9 probing points on the bed) #define AUTO_BED_LEVELING_GRID_POINTS 3 These are the offsets to the probe relative to the extruder tip (Hotend - Probe) Because directly use J-head to probe bed level, offset of X and Y should be zero. The offset of Z direction need to check up by exam, we set to zero in the first time. #define X_PROBE_OFFSET_FROM_EXTRUDER 0 #define Y_PROBE_OFFSET_FROM_EXTRUDER 0 #define Z_PROBE_OFFSET_FROM_EXTRUDER 0 Burn Marlin into RAMPS system. Execute these G code for first level detect. G28 X G28 Y G28 Z G29 G1 Z10 G1 X100 Y100 Check the Z offset Put an A4 paper on print bed, and lower Z 0.1mm once a step until J-head just bites the paper and can't move the paper easily. At this time, READ the Z POSITION FROM LCD. This reading is your offset of Z direction. Update the Z offset (Z_PROBE_OFFSET_FROM_EXTRUDER) and burn Marlin into RAMPS again. (optional) Do "Restore Failsafe" in LCD if there are old config setting in EEPROM. Update "Ptr G-code -> Prefix" in KISSlicer M104 S G28 X G28 Y G28 Z G29; Detailed Z-Probe G1 Z3 G1 X100 Y200 F3000 G1 Z0 M109 S After all, enjoy the convenience of Auto Bed Leveling!