Sharpening Router Bits
Q: How do you sharpen router bits? My husband thinks it is easier just to go out and buy new ones. John Brock: I touch mine up with a thin diamond hone from time to time as needed. My guess is sending one out to my favorite local grinding and sharpening shop would cost far more than a replacement. John Swanson: With today's geometry and materials used in router bits, it is highly recommended to have them sharpened by sharpening services that have the equipment. Sharpening usually costs about half the cost of a new bit. Richard Jones: Send them out to the saw doctor-- about $2- $4 a go. A short-term touchup can be achieved by using a small diamond or ceramic honing stone on the flat faces only. Carol Reed: Sharpening router bits changes the profile in subtle ways. If the bit is used for jointing, it is better to buy new ones. For example, if a specific dimension is to be routed, i.e., 3/4" wide dado, a re-sharpened bit could give less than that, making additional milling necessary to get a good fit into that dado. If the bit is strictly a decorative style, go ahead and give it a redressing with diamond hones to freshen the edge. Remember to use the same number of strokes on each edge to keep the bit balanced. Oftentimes, sharp edges will cut as though they are dull, when in fact they are just dirty. Use a good bit cleaner and be surprised at the results. Mark Hensley: I use the small diamond paddle placed on a block of wood to raise it off the bench. Place the flat side of the bit, not the edge, on the sharpener, and move the bit forward and back.
From the Woodworker's Journal eZine archives
For a light, routine touch-up, use a diamond hone, as directed above, on the flat inside surfaces of the bit only. You can also prolong your router bits' life and improve their performance by keeping them clean and well lubricated. Rockler's Bit and Blade Maintenance Kit will help keep both your router bits and your saw blades in good shape.