This video shows how to perform an Automatic Bed Leveling for your 3D printer, without using a sensor! Just use the hotend nozzle, instead!<br /><br />I used four pieces of adhesive Aluminum tape glued on the four edges of the 3D printer bed. Then the four pieces need to be electrically connected. I used the metallic bed underneath the glass to create the electrical connections, but if there is no metallic bed, you can use wires to connect the four pieces together. Then, you connect one wire of the z-endstop to any of the the four aluminum tape pieces and the other to a metallic part on the hotend. This way, when the nozzle touches either of the four aluminum pieces the contact will close and the z-endstop will be triggered!<br /><br />Caution: You absolutely need to heat up the hotend and wipe it clean before doing any homing or auto bed leveling procedures. The remaining plastic on the hotend will not allow the electrical contact to be made!<br />...<br /><a href="https://www.youtube.com/watch?v=XeYJkzrrM3Q" target="_blank" rel="nofollow">https://www.youtube.com/watch?v=XeYJkzrrM3Q</a>