Summary

I added rubber dampers to the stepper motors on my Hypercube 3D and they did a great job quieting the printer down. However the motors now droop due to the belt tension. So I printed out the angle adjustments which worked great, but now there is a metal piece touching the motor so the sound volume went back up some.

So I flipped them around, glued in the nuts put in longer screws and used this new piece with a rubber foot on it in order to fully isolate the motor.

Put an extra nut on the longer screw where it connects to the 3d printed piece.

With the dampers, this piece, and stepper smoothers I can only hear fan noise from my printer.

Link to the pads I used
https://www.homedepot.com/p/Everbilt-3-4-in-Self-Adhesive-Vinyl-Surface-Bumpers-12-per-Pack-49565/203661091