HYREL Y-axis belt tensioner

thingiverse

I decided my Y-axis HYREL wasn't tightened right, so I built a tensioner myself! This will only work if you have one of their newer models that uses slotted aluminum for the Y-axis arm. You might need to make your own if your dimensions don't match up perfectly, but it's actually quite easy. It requires two 10-12mm M3 bolts to attach it to the arm and one 15-20mm M3 bolt to secure a 3x4x10mm roller bearing in place. You'll need three nuts - one for each bolt - as well as ten to fifteen washers to get things spaced out correctly. Mount the bearing like shown, slip five washers between the bearing and printed part, slide two nuts into the arm about a few inches up, lightly screw in the bottom two bolts while having the bearing inside the belt, and then slide the bearing towards the idler to put tension on the belt. Don't overdo it though - just do enough so that your parts are accurate! Next, let's move on to the X axis!