Summary

The reason I built this is because its is about 10 times expensive to 3d print the nema mount, as compared to a laser cut acrylic.

Using the attached .dxf file, you can create 4 pieces for the 4 faces of a mount, and then using interlocking joints +epoxy, construct the mount.

Instructions

Created in Inkscape, Use 7mm Acrylic or metal.The triangular support is provided as single, but you need to make two.No need to flip, or mirror, just cut as is.

The square border around the shaft hole for the motor is to be etched, not cut.

The design has been optimised for use with 7mm acrylic.
If you choose a thinner acrylic, it would be fine, but it would not be able to hold the weight of the motor+the belt tension on the shaft.

Using an acrylic thicker than 7mm will be ideal, but there could be gaps in the joints, which help in gluing the mount.

The vertical slots on the bottom plate are 4.2mm wide and 30mm long. The distance between their centers is 30mm.

The motor mounting holes are 3mm in diameter, and the shaft hole is 22.5mm in diameter. The interlocking joints are 7mm long, and 5mm wide.

Laser Cut Nema 17 Mount