Slip Roller by Jim In Idaho -- I've spent most of my time, for the last 3 weeks building this 24" slip roll. Modelled on Vince Gingery's design, but with 2" heavy-wall tubes, with solid ends, and 3/4" bearings rather than 1/2". Should easily handle 16 ga. material, and probably 14ga. I made a few other improvements, also....
