Precision opto probe for auto bed leveling

This thing gives you the ability of probing your heatbed with all the benefits of an opto endswitch - like a constant switchpoint and almost zero wear-out. A minimum of moving parts and a maximum of reliability.

Workload / Time :

• About 30 min. for printing
• 20 min. for modifying the screw (can be done while printing)
• 5 min. for assembly / adjustments

= Total: ~ 35 to 60 min.

Instructions

1. Print the probe body.

   • Versions for Graupner Servo Family
   • Versions for SG90 9G Micro Servo

   Each type is available for mounting the arm either from top or back (reverse).

2. Things to buy (vitamins):

   • 2x M5 nut
   • 1x M5x40 screw
   • 1x spring about 14mm length, 7,3 mm width (or whatever fits)
   • 1x Opto endstop with TCST2103 (standard) type light barrier

3. Use a file to form the upper end of the screw into a flat swordlike surface (length about 10 - 12 mm).

4. Remove screw head from the other side and form a tip end with the file.

5. Assembly :

   • Slide the screw into the body (swordalike end first). Add the two nut and the spring.
   • Put the sword end into the slot and move both nuts down the thread.
   • Adjust the moveable length of the screw by turning the nuts.
   • Fix the nuts by turning against each other.
   • Attach everything to the servo by using a standard servo arm. Probably an additional small hole for the fixing screw must be drilled.