We’ve covered DIY Dremel bits before. It’s easier than you might think to make some of the bits used with Dremel and other rotary tools.
In this video, Steve from The Small Workshop, shows you how he creates his own sanding drum bits using dowel stock and cut strips of whatever grade and grit paper (and drum diameter) he chooses.
We’ve seen other methods that involve creating tube-type sanding drums that can fit on a traditional rotary tool mandrel. Here, Steve simply glues the sandpaper to dowels of desired diameters and then creates a custom mandrel that screws into the center of the dowels.
Making your own drum bits this ways is probably not cheaper than buying commercial sanding drums (which aren’t all that expensive), but this method is easy, quick, and it gives you a world of options in terms of the sandpaper used and drum diameters you might desire.