@fcwilt good to know... its possible that if it is that fragile something may have happened during shipping to make it inoperable.

The probe i purchased (for just under $19) is this one:

https://www.amazon.ca/gp/product/B07DGZV9C8/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

it is a 3dTouch "clone" of the BLTouch as i understand it.

I purchased it since it was being sent domestically. and I'm sick of waiting 3 months or more for parts.

The wires for my unit are as follows:
3 for the servo:
black (grd)
red (+)
Blue (control signal)

2 for the "probe".. presumably
black (grd)
yellow (Z Min)

I'm presuming that you are referring to the yellow wire in my case... but yes, the angry pixies (electrons) are flowing freely according to my multimeter. Is it possible that I have incorrectly identified this connection in the settings? im not sure... been staring at it for far too long... need a break. eyes going crossed.

• Double check your wiring and crimps:

Used multi-meter to check wiring – all points are good, and showing resistance. wiring is exactly as described in the previously posted photos/diagrams...

• Make sure you're actually connected to the pins you think you are. 

Yes.

• Are you using heater pin 7 or heater pin 3? 

Heater pin 7 for the control signal for the servo. “blue wire” in my case.

• If you give the probe some clearance from the bed you can do some function testing by sending M280 P7 S120 I1 to put the probe into self test mode. It should start deploying and retracting the pin. If you touch the pin it should retract and go into alarm and start flashing. Then use M280 P7 S160 I1 to release the alarm. If that works consistently we can move on to the next test. 

Passed. No problems there.

• Raise the print head and probe a good distance above the bed. Manually send G30 in the console. The pin should deploy and start to move towards the bed. Touch the pin with your finger to trigger it. If it stops. Good. If it doesn't, kill power. Re check wiring. 

This is where it fails. And yet, the wiring is good. Honest.

The servo controlling the probe movement is working fine. The probe ‘sensor’ that sends a signal to the board when it touches something is not working. Either I have a defective probe (signal not being sent) – or my settings are off (signal not being received).

I'm still hoping that its my settings... returning the probe for a replacement is likely going to be challenging.

Again, many thanks. i just hope that I /we can get it working. At the very least, it may help others in the future with similar problems.

kind regards.

Thank you very much for your help. After years of research and months of building, I can almost see my newly printed prosthetics from here!

But, I’m not quite there it would seem, and again I need to call on the collected wisdom of the masses.

In response to your your kind suggestions:

1: G1 Z0
I did set G1 Z0 intentionally… the reason was that, on occasion, only one of my 2 z axis motors would engage when the G1 command was set… but this only happened during the homing process. For now, I simply make sure that there is some head space before homing. I will return to this issue once the more “show stopping” issues can be addressed.

2: Your Y position value
Yes it is! I hadn’t noticed it until you pointed it out… no idea why or how it got set that way. It wasnt causing any problems, so I had no reason to look I guess. Fixed.

3: remove the M98 Pretractprobe.g and M98 Pdeployprobe.g:
Done. Thank you.

4: Measure G31 Z value set:

This seems to be where I am making my mistakes it would seem.

Unfortunately, I am unable to get the printer to “pass” the dynamic test, making further calibration impossible as I understand it.

1: I manually home the z axis by way of G92 Z0
2: I centre the hot end in the x-y plane
3: I enter G30 s-1
4: the probe extends and the bed rises to meet the hot end.
5: The probe quickly retracts and extends once the bed makes contact.
6: The bed stops at height 0.000
7: The led in the probe blinks rapidly
8: The control board reports back the error: Z probe was not triggered during probing move.

As for wiring, I have followed the diagram provided on the attached wiring diagrams:

I included the required 220 ohm resistor.

My sense is that I am not directing the control board to the correct pin for the sensor… but I could be wrong.

Again, any kind advice is greatly appreciated.

BACKGROUND:

I'm building this printer so that I can assemble prosthetic devices for myself and a friend who is also missing appendages.

Please note that on a scale from one to 10, my knowledge level is about a 4… OK, 3. possibly 2. Does the scale accept negative integers? Anyhooo...

Mechanically, my printer is a core x-y that started out as a Tronxy X5S-2E. Due to the absence of a controller board, it is very recently being controlled by a duet-wifi version 1.02, with firmware 1.21 (2018-03-21). (Gearbest sent the wrong board with my kit).

CONSIDERATIONS:

Most recently, I have successfully figured out how to home the x and y axis, and can control movement of the hot end in that plane. I have also managed to get M401 and M402 to work in extending and retracting the probe.

Here are my config files:
4_1537151161381_retractprobe.g
3_1537151161381_homez.g
2_1537151161380_homeall.g
1_1537151161380_deployprobe.g
0_1537151161379_config.g

ISSUE:

Homing z results in the bed colliding past the extended 3d-touch probe and into the hot end before I need to quickly shut it down. I am assuming that it is not registering the probe for some reason.. but i cant figure out why.

I would be very grateful if someone could help me understand what I am doing wrong so that I can move on to the next challenge.

My sincere thanks for your kind consideration into this matter.

References:
https://betrue3d.dk/bltouch-on-duet-wifi-configuratio-and-usage/#changeconfig
https://betrue3d.dk/bltouch-on-duet-wifi-duetreprapfirmware/
https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#BLTouch
https://duet3d.dozuki.com/Wiki/Using_servos_and_controlling_unused_IO_pins