Hello! I think there is a mismatch between the scale on some of the models here. When I download the STLs, the inserts fit into the frame fine, but the bench assembly itself is dramatically too small for the frame. Also, when I printed the barbell that you have as another model, that barbell is not scaled properly to the size of the frame in this model.

Any chance you can confirm that all the scales are correct on both models?

Very nice project!