Making a Flap Sander Homemade Woodworking Tools

For my house renovations, I’ve been making my own window trim. One part, the apron under the stool, is a cove molding I cut on the table saw. Using the saw to make that cut is fairly efficient, but takes some time. Another drawback is that it leaves a finish that is a bit too rough – it needs to be sanded. I though about the quickest way to do that and came to the conclusion that it would be best if a machine were involved, given how many of these I would have to sand. I figured a flap sander in a drill would work well, so that’s what I made:

Really simple to make, it’s just a plywood core with slits cut and sand paper glued in. A bolt acts as an arbor to mount it in the drill.

To get started, I drew a circle with my compact compass:

I then roughly divided it into sixteen sections and cut in about 3/8″ with the band saw.

For the sand paper, I used a new sanding belt and cut it into 1″ wide strips. I made a wooden template (arrow) to trace out the shape on the strips so I could cut each flap out:

Then it was just a matter of gluing them in. I used polyurethane construction adhesive, but any strong glue will work.

I made a video showing how I made it:

I also made another type, a mop sander:

And a smaller flap sander.
This is the kind of project that can be done in an hour, or so, and is really handy to have. If you use sanding belts that have been used, these can be virtually free to make.