I created this bushing to support a ¾" square tube on each end where I would insert a threaded rod.  It will be put to the test for compressing a LiFePO4 battery bank.

At the moment, I only have 2 sizes of the model available:

5_16in ID x 5_8in Square x 5_8in Long Bushing.stl
3_8in ID x 5_8in Square x 5_8in Long Bushing.stl

My threaded rod was 5/16", and so I thought that allowing for clearance I would need a 3/8" hole.  I had forgotten that I already allowed for a a 0.1mm tolerance on both the inner diameter (larger) and the outer dimensions (smaller).  The result was that the 3/8" version had a very sloppy fit.  So, I created a 5/16" version and it fits perfectly.  There's nothing wrong with the 3/8" version, but it's for an actual 3/8" rod.  :-)

NOTE:  You may need to run a rod through the center a few times to clean up any Z-seam or PLR blobs.  But, assuming your dimensions are dialed in, it will fit smoothly once you do.

After I finish with my battery project, I'll post some STLs for other sizes.  But assuming that I don't do so in time or don't create the size you need, you can access my fully parameterized CAD document on OnShape here:

https://cad.onshape.com/documents/5ab8be0eb589f80654b3a70e/w/de594c941ade0ccc98efcb0b/e/ee2ed43c8844a52a0cf7a916

Please post any makes!

 

Cheers!

&

Always Be Printing