This a very neat sand tip, well worth the effort :yes4:
Belt Sanding Block / Bloc de ponçage à courroie de papier abrasif « Atelier du Bricoleur (menuiserie)
Gene, any sanding device with a soft backing will tend to round edges off. Cork is a little stiffer so not so bad. When I worked in a mantle factory we used to make sanding blocks similar to this except we would just cut strips off the belts and glue them with regular wood glue to mdf. They last an unbelieveably long time because they don't flex. Every shop should have a few of them around with different grits.Great idea.
Could cover the flats with self adhesive cork or thin foam padding, too.