Source for brackets with 25mm on-center slots instead of 30?

Every NEMA 17 bracket I've found has 30mm on-center mounting slots. Does anyone have a source for ones with 25mm on-center slots? OR slots that run perpendicular to the motor shaft instead of parallel?

I need to mount to 50mmx50mm extrusion (8020's 25-5050 stuff) where the shaft is parallel to the length of the extrusion.

I don't believe that "on-center" is a term for anything. Based off of your description, do you mean an 90 degree bracket with a 25mm center to center hole spacing for the mount? If you found what you want, but with the wrong spacing, just modify the part. A drill or dremel is all you need. If you want to make something, angle aluminum is easy to work.

Get a piece of 2" square or 2" x 1.5" aluminum tubing. Drill holes for the motor shaft and mounting screws. Drill holes in the side or bottom for mounting the mount on the t-slot. No fancy tools needed, motor will be electrically grounded (assuming you ground the printer's frame- and you should), aluminum mount will carry heat out of motor, it won't flex when you apply belt tension, it won't creep or distort over time.

You can cut aluminum tubing with a hack saw and drill it with any drill. The NEMA-17 motor has a 22 mm diameter bump (not sure what the technical name for that is, maybe a boss?), so use a 7/8" or 1" drill to make that hole. If you use standoffs between the motor and the aluminum tube you can just drill a 1/4" hole for the motor shaft, but then you lose most of the heat transfer via the mount.

In the picture below, the tool access holes for mounting the motor also serve as holes to mount the mount on the printer. You can mount the mount on either side or the bottom just by drilling the necessary holes.





And then you can print some nice covers:



Edited 1 time(s). Last edit at 05/14/2018 10:46AM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Thanks guys. The idea was to just buy off the shelf.