Sanding round-overs on several dowel ends can be a trying task, especially when you want the round-overs to match.

Do the job with your table-mounted router. With a piloted round-over bit of appropriate radius in the router, set the depth as you would for rounding-over any edge. Then, clamp a fence to the table with the distance to the center of the bit equal to half the dowel's diameter, as shown above. Turn on the router, and then slide the dowel along the fence into the bit. Rotate the dowel to form a perfect round-over.
—From the WOOD magazine shop