In the Nema 17 linear actuator bundle, the aluminum spacer used is 40mm long. This in conjunction with a 45mm M3 screw leaves about 1-2mm of available thread to hold the motor in place (which seems quite small for something that will move and vibrate about). Was this a typo in the part store, and should I go with a 35mm spacer instead?
This seems a bit odd as they used to recommend the 1.5" spacers which are a perfect fit. Even the M3 cap head screw page says they go with the 1.5" spacers.