Anti-Wobble Anti-Backlash Auto Bed Probe for Prusa i3 (Cheapest)

thingiverse

Outdated-Discontinued Update1 4/4/2016 : -Using two endstops connected in series at either sides of the x axis will improve the leveling repeatability. Just flip the part and print for the X-idler side. -Changing the probe grid points to 2 (4 points placed at the most rigid areas on the bed which are usually above the linear bearings will make z offset measurement more consistent. This part is the cheapest and most effective improvement implemented on my homemade Prusa i3 . I designed this thing in the need for Auto Bed Probing, by remixing the design done by jamesarm97 -Thanks to him- and adding a holder for the micro switch from an old computer mouse. Surprisingly, The print quality and machine reliability improved significantly in the following ways: 1.ANTI_WOBBLE : Better layer alignment by eliminating the tension between X - Z axes and preventing the bent Z screws making X axis wobble. 2.ANTI_BACKLASH : Basically preventing backlash by using two nuts and a spring separating them. 3.AUTO_BED_PROBE :Compensating for unlevel build platform by Auto Bed Probing and setting Z offset matrix which leads to perfect first layer adhesion and perfect finish on faces printed directly on glass (PLA). 4.Replacing the unfriendly Z end stop which required constant adjustment. Changes in Configuration.h in Marlin Based Machines : 1- Inverting your Z min end-stop setting. Normally, Z end-stop is closed when Z axis homes, We want it to be open when Z axiz homes. const bool Z_MIN_ENDSTOP_INVERTING = false; 2-Activating auto bed leveling by delete "//" define ENABLE_AUTO_BED_LEVELING 3-Update these setting for the probing grid define LEFT_PROBE_BED_POSITION 50 define RIGHT_PROBE_BED_POSITION 150 define BACK_PROBE_BED_POSITION 150 define FRONT_PROBE_BED_POSITION 50 3-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 2 4-Set the probe offsets : These are the offsets to the probe relative to the extruder tip (Hotend - Probe) As we directly use the hot end nozzle to probe bed , offset of X and Y will be zero. Setting the Z offset needs trail and error, set to zero in the first upload and re-set it by using a sheet of paper as the gauge and reading this value on LCD as the hot end touches the sheet.My measurements leaded to 1 mm offset which would be different depending on the build platform rigidity. define X_PROBE_OFFSET_FROM_EXTRUDER 0 define Y_PROBE_OFFSET_FROM_EXTRUDER 0 define Z_PROBE_OFFSET_FROM_EXTRUDER 0 Start G-code for the slicing Software : M104 S G28 X Y G1 X100 Y100 G28 Z G29 G1 Z0 M109 S Print Settings Printer Brand: RepRap Printer: Home made Prusa i3 Rafts: Doesn't Matter Supports: No Resolution: 0.23 mm Infill: 30%