Simplified underbed piezo sensor mount

thingiverse

This is an upgrade of my integrated bed mounting and piezo nozzle contact sensor design found at https://www.thingiverse.com/thing:1399512, as illustrated in this sectional drawing. A 27mm piezo disc with a hole drilled into it is attached between the carriage and bed adjusting nut. The piezo can be mounted directly on a flat surface of the carriage under a pad for minimal compliance; or it can be attached to the ring abut without a pad, resulting in better sensitivity but more compliance. Additional information regarding this topic and others can be found at http://forums.reprap.org/read.php?1,635075,page=1. Two nuts are provided for use with 3mm or 4mm bed jacks. A nut, preferably made of Nylon or Nylock, should be glued into the recess. An amplifier/conditioner can be built DIY or purchased from https://www.precisionpiezo.co.uk/shop. When drilling a hole in the piezo element, it is essential to use a sharp drill and secure the piezo to a flat surface using strong tape. A 5mm hole should be drilled for a 3mm jack or a 6mm hole for a 4mm jack. The ceramic powder generated during this process may be hazardous, so proper clean-up of the powder is crucial.