Wednesday, August 21, 2019

Printer: ABL Assisted Bed Leveling

ABL still needs a fairly level bed for it to do its thing. I've found if your bed is within 0.2mm of level, then ABL will work great. Fortunately, once you have ABL installed, you can use it to help level your bed. Using the ABL is fast, easy, accurate, and you let the printer do most of the work.


After you open a terminal to the printer using Octoprint, Pronterface, etc., send a G28 to auto home the printer, then add a G29 to do an ABL pass. Once the pass is complete, the ABL's matrix of measurements in millimeters will be displayed in the terminal window. The top left number is the front left corner, and the top right number is the front right corner.

The ABL measurement matrix returned to the terminal after completing the leveling pass.


On the Ender 3 the bed leveling M5 screws have a 0.8mm pitch, so each full revolution of a leveling wheel will move the corner 0.8mm. Once you've adjusted the wheels, send another G29 to the printer to do another ABL pass, and keep adjusting as necessary. It's usually taken me three passes to get all my corners within 0.2mm of level.