Summary

This is useful if you want to join too shafts together. It was originally designed to couple a stepper motor to a knob through a flexible drive shaft.

Instructions

Measure the two parts you want to couple.

Decide what screw size you want to use. (Default settings are for an 8-32 screw.)

Enter the information into customizer and print your model.
I recommend looking up the tap drill size and using that for the screw size.

The .scad file will also create a divot in the male shaft. The radius is the same as your screw size parameter. This is meant as the contact point for a screw, to prevent slippage.

Clean up the screw hole in the female end with the appropriate drill if need be, then thread it with the appropriate tap.

A final note, the coupling is designed to be printed in the configuration generated by the .scad file. The top, inside of the female coupling is a 45Âº cone to allow a printable overhang with no hang-offs.

Photo caption:
I used and 8-32 nylon screw with my printed coupling and that works great. The female end is attached to the knob of a linear translation stage, which holds a sample tube. The male end is joined to the coupling of a flexible drive shaft (http://www.mcmaster.com/#flexible-drive-shafts/=mkxgvu), held in place by the drive shaft's hardware. This shaft is in turn, attached to a stepper motor, controlled using an Arduino equipped with an Adafruit motor shield. This was used as an easy, affordable way to continuously raster a photoactive sample over an excitation laser for resonance Raman spectroscopy.

Customizable M/F Shaft Coupling