Printrbot Plus V2.1 X-axis Spreader

thingiverse

I faced issues with my PrintrBot Plus V2.1 printing very tall objects, where the Z-axis guides wobble led to slightly overlapping sides near the top of the Z-axis. This causes X-axis belt tension to become loose, despite being tight at the bottom. I resolved this by installing a tensioner across the guide bars using a 12" long 1/4-20 rod, two hex couplers and custom-printed brackets. I printed these brackets in PLA and found that the couplers fit well within them. You can make coarse adjustments to the tension by rotating the couplers to loosen or tighten on the threaded bar. For finer tuning, remove the coupler from the bracket and turn it a little more than a sixth of a turn. Once the desired level of tension is achieved, secure the brackets on the ends of the Z-axis guides with 6-32x1/2 screws and nuts.