OpenFlexure Microscope Mods To Fit NEMA17 Stepper Motors

This is part of the research for The μRepRap micron scale 3D printer project RepRapMicron. It has now been superseded for that purpose by a Block stage version https://www.printables.com/model/876888, but is still interesting in its own right.

The OpenFlexure microscope stages (one for transmission microscopes, and one with an indirect lighting stage) have been reinforced to hold the extra weight of the heavier NEMA17 stepper motors, and the adaptor plate allows the motors to fit on and turn the axis gears. I remodelled the original axis gears with collars that fit NEMA17 motor shafts. You will need to print 3 gears, and they have insets for an M3 nut and set screw. Ideally you'd have a flat on your shaft, but the torque is low and you might get away without it.

Electronic

This allows standard 3D printer electronics (I'm using Marlin on a RAMPS 1.4 board) running GRBL Servo https://github.com/robottini/grbl-servo to control the movement of the stage with micron accuracy. The motors are fixed to the adaptor with 2x 10mm M3 screws, each adaptor attaches with 2x 15mm M4 screws, and washers are advisable.

You will need the standard large gears from OpenFlexure, as well as the feet and O-ring tools in order to complete assembly. A few nuts and bolts are required, details at OpenFlexure above.

Probe Arm And Feet

There is now a probe arm that fits to the side platform on the indirect lighting stage, and feet that incorporate microswitch endstops https://www.printables.com/model/827788 .  This lets you drive the Delta Stage using a portable Python GUI that runs the XYZ axis as a delta robot: https://gitlab.com/reprap/reprapmicron .

Licencing And File Building

Note that the OpenFlexure Stage models are under the CERN Open Hardware Licence v1.2 and the adaptor plate and gear I made is GPL 3. If anyone would like the tarball of the source files (though I recommend getting them from OpenFlexure), please ask in the comments below. My stage mods are manually placed in PrusaSlicer, rather than integrated with the source (which produces a non-Euler model) so you'll have to add those bits yourself.