Summary Noticed some lines in my print's on the X plane, and found the belt was rubbing on the angles towards the top of the 2040 my X axis uses. So I quickly mocked it up in tinkercad and printed one out, and it works great! I'll need to sand down the spacer to get the alignment just right, then I'll make another measurement and update the files so you shouldn't need to. For now it's better than my belt rubbing on the metal though! I'm currently using the one in red and it's a tight fit (idler very close to the 2040), so I widened the design for the one in green, but haven't printed it out to test yet. Shouldn't be any issues, the holes vertical alignment is what mattered most to me and that's spot on.