I have made this tool from some scrap material and some 3d printing to help me tramm my print bed. It is based on the idea that I have seen in this video: https://www.youtube.com/watch?v=715Xop79Sus The idea is that you first align the nozzle exactly to touch the surface of the print bed when it's Z position is set to 0.00mm, then you lift the nozzle, put the probe underneath it, and lower the nozzle down by very small steps until the LED just lights up and note down the exact current Z position. This is now the reference height of your tramming tool. You only need to do this step once. (I also noted the temperature of the bed and nozzle at which the tool was applied. I choose 150°C for the nozzle, so it is not oozing, but the filament that oozed out can still be removed.) Now you go to each corner of the print bed lift the nozzle, put the tool beneath, lower the nozzle back to the reference height and adjust the bed levelling knob of the print bed until the LED just lights. I find this method much easier, faster and reliable than watching the bed carefully from the side or dragging paper under the nozzle. Note also, that dragging paper under the nozzle introduces small gap between the nozzle and the bed, which is wrong. The distance should be zero, since the G code lifts the nozzle to the height of the first layer when it starts printing. ** Ofcourse you don't need to always manually move the hot end. Here's a piece of G-code to move the hot end to 4 corners and down and up and wait for a button press each time. ;Bed leveling aid. ;Change X and Y coordinates, if your bed is not 200x200mm! G28 ;home al l axes G1 X20 Y20 Z20 F2000 ;corner 1 M0 ;wait for user G1 Z12.06 F1000 ;down M0 ;wait for user G1 Z20 F1000 ;up G1 X180 Y20 Z20 F2000 ;corner 2 M0 ;wait for user G1 Z12.06 F1000 ;down M0 ;wait for user G1 Z20 F1000 ;up G1 X180 Y180 Z20 F2000 ;corner 3 M0 ;wait for user G1 Z12.06 F1000 ;down M0 ;wait for user G1 Z20 F1000 ;up G1 X20 Y180 Z20 F2000 ;corner 4 M0 ;wait for user G1 Z12.06 F1000 ;down M0 ;wait for user G1 Z20 F1000 ;up G1 X100 Y100 Z20 F2000 ;go to center ** The here supplied STL file is of the box in which I safely store my reference tramming tool. ** Tips and support kindly accepted here: https://paypal.me/ZigaM3 Or with LBRY (LBC) credits, through my Odysee channel: https://odysee.com/@ZigaMDIY:9 I also design on redbubble: https://www.redbubble.com/people/reintegration/shop And I promote my RB designs on Pinterest: https://www.pinterest.com/reIntegration42