Alien Z Probe for 3d Printer

An auto bed levelling probe with significantly greater accuracy than a conventional microswitched probe. The probe incorporates an auto deploy and retract mechanism which is springless, decreasing the effector load. We have repeatedly taken sub 50micron readings using this probe.

3D printer parts and enhancements

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Refer to youtube video for Assembly

Also a video of it in use

Just remember to glue a little magnet to the top of the rotating arm (top deploy arm) and half a small washer to the top left side of the Terminal Contactor Plug.
The welder rod will need snapping off at the correct length for your printer, the Kossel Mini required 20mm removing.
The 1.6mm CK standard collet may need the ends adjusting so the rod slides freely. The collet can be moved up and down in the collet body to adjust the probe for your printer.

Setup: (For Kosel Mini)

Set in Configuration.h
define Z_PROBE_OFFSET (0, 24.0, -2.08, 0)

Set in Marlin_main.cpp
void deploy_z_probe() {
feedrate = homing_feedrate[X_AXIS];
destination[X_AXIS] = 0; // T3P3 Kossel Mini R2
destination[Y_AXIS] = 67; // T3P3 Kossel Mini R2
destination[Z_AXIS] = 22;

feedrate = homing_feedrate[X_AXIS]/10;
destination[X_AXIS] = -23; // T3P3 Kossel Mini

void retract_z_probe() {
feedrate = homing_feedrate[Z_AXIS];
destination[Z_AXIS] = current_position[Z_AXIS] + 40; // T3P3 Kossel Mini R2

destination[X_AXIS] = -40;
destination[Y_AXIS] = 60 ;
destination[Z_AXIS] = 40;

// Move the nozzle below the print surface to push the probe up.
feedrate = homing_feedrate[Z_AXIS]/10;
destination[Z_AXIS] = current_position[Z_AXIS] - 35;

feedrate = homing_feedrate[Z_AXIS];
destination[Z_AXIS] = current_position[Z_AXIS] + 30;

Materials and methods

- 175mm by 1.5mm Tig Welder Electrode (any type will do)
- 1.6mm CK Standard 3 Series Collet Body
- 1.6mm CK Standard Collet. 3 Series
- 10mm od, 4.3mm id washer or similer, 1mm thick. (Mine is a Meccano One)
- Small Neodymium Magnet
- 3mm x 12mm Caphead
- 2.5mm x 12mm Caphead
- 3mm x 80mm Rod (I used Meccano again)
- Thin Wires
- Set of Printed Parts



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8dfe125c354bd29a13e4001abcd883f7?default=blank&size=40Armaghan Mallik added this to the Kossel Clear collection ago
E8aacb6d060f9a6306ed9b8fb9affceb?default=blank&size=40Jochemczyk & Ward published this design ago