Calling all engineers. I have a materials question. I am working on building an IPF (International Powerlifting Federation) style combo rack. You can do squat and bench press with it.

My current issue is deciding on a material for a part in it.

The combo rack that I am essentially copying.


The tapered rollers in the above photo are my question. They appear to be made out of cold roll steel. I would like to make them out of a plastic to save the knurling on the bar. I am looking for suggestions on a plastic that would somewhat last if it exists.


Thank you all for any suggestions that you might have.


I have made a new drawing with some of suggestions I have received. Does this design seem better?