Up Mini 2 X-Axis Tensioner

thingiverse

The Up Mini 2 x-axis stage is notoriously fragile due to a flimsy injection molded plastic piece that holds the idler pulley in place, always under immense stress. I sought a swift and uncomplicated solution, so designed this fix. It replicates the original geometry of the molded part, extending the base to accommodate a mounting hole through the circular mark left by the injection tool. This ensures a precise reference point (14.5mm behind the tangent edge of the bearing slot for the first drilled hole). The new component should then be screwed in place, and the second hole can be drilled accordingly. Prior to creating my own design, I reviewed two other options - https://www.thingiverse.com/thing:3461323 and https://www.thingiverse.com/thing:3987766. Both have drawbacks, such as restricting full stage travel or requiring arbitrary holes to be drilled. A comparison picture shows the original in the middle, my design on the right, and the other closest design on the left. Your specific situation may dictate which style is better suited. This fix requires two 2.9m x 6-9mm self-tapping screws. I use McMaster-Carr 94997A225 and 94997A250 due to their convenient availability. Any similar screw should work effectively, or you can enlarge the new part hole slightly if needed.