OptoServo Probe

I had so much problems with my 3D Touch that I decided to create an alternative. Several designs exist combining an optical endstop and a small SG37 servo, but they typically were too wide for my taste and I wanted the probe point to be as close as possible to the nozzle - if possible only offset in one of the main directions.

The result is this design. It has offsets of (-40, 0, z) where z depends a bit on how you mount it. My mount isn't ideal, but I'm sharing the Fusion 360 file for those wanting to build on this.

The M48 probe test with parameters L3 P25 S1 V4 yields (full results in included file):

Mean: 0.011500 Min: 0.005 Max: 0.015 Range: 0.010
Standard Deviation: 0.002915

This might not be the best probe ever, but it's way more reliable than the bad 3D Touch that I had and with a range of 0.01mm over 25 probes should be more than enough for good bed adhesion.

I have included the 3MF file I used with PrusaSlicer to show how I printed it without supports. You obviously do need an optical endstop, an SG37 servo and some M3 (countersunk) bolts and nuts.

Print Settings

Printer Brand:

Creality

Printer:

Ender 3 Pro

Rafts:

No

Supports:

No

Resolution:

200

Infill:

30

Filament:
Balco (stay away from it, it's crap) PLA Black

Notes:

I used a tiny screw as the metal lead at the bottom. This somewhat evens out the surface probed. You need to trim the two mounting "wings" from the SG37 to fit it in place.

Category: 3D Printer Accessories