Mylar V3

A project log for Delta Printer - Capacitive Nozzle Probe

Test accuracy and consistency improvements of a capacitive bed probe triggered by contact with nozzle.

mulcmumulcmu 05/10/2024 at 23:510 Comments

With the ESP32 dev module hanging off the umbilical and a long wire lead leading down to the copper probe, it was difficult to avoid small movements of the probe wire during operation.  The small changes in wire position and long wire was negatively impacting sensitivity and repeatability.  The copper foil also seemed to be wearing/bunching from the nozzle contact.

V3 redesigned the mylar mount to use a 15x15x0.3mm shim.  This is pretty thin but rigid enough to keep from bending.  The shim mounts on the bottom of the mylar with double faced tape.  There is a hole in the mylar for the nozzle to pass through an make contact.  An ESP32-S3-Zero dev module is mounted to the rear mylar arm.  This lets the wire lead from the board to the probe be short and independent of any umbilical motion during movements.

The Arduino code was updated for testing.  The S3 touch sensors operate a bit differently than the plain ESP32.  No major problems getting the code back up and running, now with an RGB addressable led for feedback.  Initial testing looks like there is improvement.  Next step is to power the dev board via the printer probe connector.  The USB-C cable hanging off the side of the mylar isn't ideal.