Simple sanding cylinders. I made the first ones from wood but there are limited in the diameters I can drill so here are cylinders with 15, 20, 23, 30, 40, 50 mm diameters. All of them are 115mm in height which matches rolls of Bosch sanding paper (https://www.amazon.de/gp/product/B00141637I). The spindle hole is 8mm in diameter, so it matches M8 threaded rods (which are 7.8mm in diameter) within some tolerance. I assembled them with 3 hex nuts and 17cm long threaded M8 rods and my drillpress bearing (link), strong doublesided adhesive tape and sanding paper