@BlueDust said in Precision Piezo z probes guide for duet users reference:
@en_passant
Try swapping the wires from the Piezo Sensor to the Piezo motherboard.
If the Piezo triggers on press, its correct, but if it triggers on release try swapping the sensor wires and see if that fixes it.
I feel like I'm endlessly trying to get my underbed piezo's work. I'm using the Precision Piezo – Piezo Z-Probe Universal Kit V2.75
I'm using analog settings and have my bed setup in such a way that the piezo is supported along the edged and another part presses into the center.
It worked okay before, I have tuned them to be as sensitive as I can get them, when I read the comment about reversing polarity of the discs I was intrigued and it appeared that my discs would also only get a signal upon release and not upon depression of the bed.
So I turned around the wires for the discs and it actually made it way worse. Now the nozzle has just been pushing into the bed so hard that it deformed and damaged my printing surface.
Reversing the polarity again back to how I think it should be, the probing works a lot better but still it tends to push hard into the bed, just not as hard as to damage the surface.
There once was a time where my setup worked better, having a near-hair trigger. I would like to find that again.
Are there other things I can try such as tuning the dive speed for each probe? I have seen some people use this underbed piezo setup with great success and it looks like their probing scheme moves much faster than mine. I'm thinking a faster dive speed might also help with getting better readings.
These are my current settings:
M558 P5 R1 C"!probe" H2 F3000 T6000 B1 ; set Z probe type to effector and the dive height + speeds
G31 P100 X0 Y0 Z-0.216 S0
I also find it hard to get an exact adjustment on VR2, it's either triggered by me tapping the frame and only a fraction of a turn, and it barely registers tapping on the bed.
Update:
Just wanted to add that I have been tuning the feedrates for probing a bit and raising the speeds have helped make it more precise.
This is what I got now:
https://youtube.com/shorts/eEXjATJ_640
The only issue being that the machine doesn't seem to print perfect first layers across the bed. Would a Delta printer require a mesh from G29? The bed is perfectly flat (alu bed), even when heated.
I'm thinking any typenof distortion is still caused by the auto calibration despite consistently hitting sub 0.03 deviation as can be seen in the video.