This is a sensor mount for David Crocker's mini height sensor board. You can find the details here:

https://miscsolutions.wordpress.com/mini-height-sensor-board/

The sensor mount is positioned on the back of the Frankenstein and replaces the small X axis limit switch holder, which is integrated here.

The sensor board is mounted on the inside of the mount with its back facing towards the nozzle.

08/09/17 - new Version v2:
- back parts thickened for better stability
- moved sensor 5mm further towards the nozzle (now it should be 33mm behind)
- removed endstop mounting plate (not used on my printer, because the endstop switch is mounted on the left side of the x axis

Setup parameters

Z Probe offset in Marlin

You have to modifiy the probe position in your Marlin source accordingly. This mount positions the board directly behind the nozzle, so

• X_PROBE_OFFSET_FROM_EXTRUDER should be 0
  (from David Crocker's page: "The sensing area is approximately in the middle of the bottom edge of the board, below the cylindrical capacitor.")

• Y_PROBE_OFFSET_FROM_EXTRUDER should be somewhere in the range of 30 to 35 mm (positive values = behind the nozzle)

Z Probe bed position

As the probe is exactly behind the nozzle you should be able to take measurements relatively close to the right and left edge of the hotbed. Perhaps values like

• LEFT_PROBE_BED_POSITION 15
• RIGHT_PROBE_BED_POSITION 205

should be fine.

For the front you need to take into account, that the sensor is behind the nozzle, so if the nozzle is at 0, the sensor is round about at 30 or so. You can perhaps try it with

• FRONT_PROBE_BED_POSITION 45

The back position is opposite to the front, so perhaps you start with somewhat like

• BACK_PROBE_BED_POSITION 175

FOR SURE YOU HAVE TO FIND OUT THE EXACT POSITIONS ON YOUR OWN. I can't be held responsible if anything goes wrong! Just be warned ;-)

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