Prusa MK3, MK2 X-Axis Belt Tensioner

prusaprinters

<p>I had a difficult time getting the belt tension I was looking for when assembling the original MK3 printer. I wanted more adjustment then what is available by rotating the stepper motor when tightening. Once assembled it is also difficult to get back in and tighten the belt on the X-Axis carriage. So I designed a simple plate that mounts to the motor and has slots to allow for tightening the belt. Assemble the plate on to the X-Axis motor with (4x) M3 x 10mm screws, I had these in my Spare Parts Bag. Install (3x) of the square M3 nuts (also in Spare Parts Bag) in the slots then assemble to the mount, leave slightly loose. I used a screw driver between the motor and the frame for leverage to get the belt tight and then fully tightened the 3 screws. I also flipped the pulley on the motor around 180 degrees so the belt was aligned inside the slot.</p> <p>The 1in model has a 1.0in center hole for the stepper motor instead of 22mm on the original.</p> <p>I don't believe this works with the new updated MK3 design with built in tensioner, but shouldn't really be needed on that design anyway.</p> <h3>Print instructions</h3><p>Printed on MK3 with standard PLA with 100% infill and no supports. I had the counterbored holes facing down, and just needed a little cleanup inside them after printing.</p>