Q: Can you suggest a method to sharpen drill bits and blades? - Rick Dominic, St. Catharnes, Ontario, Canada
A: A bit-sharpening machine will sharpen tips but not blades. The Drill Doctor (the most common brand) costs about $80. Considering that many smaller bits cost only a couple of bucks, you might wonder whether you’d be better off just pitching dull bits.
The answer may be no. You may drill a lot and don’t want to waste bits that can be sharpened. Your bits may be big and therefore more expensive than smaller ones. Or perhaps you like the results you achieve using finely honed bits.
Though the process can be painstaking without a bit-sharpening machine, you can sharpen bits by hand. You can file all edges of a spade bit and then stroke the edges on an oil-lubricated whetstone. To sharpen twist-bit tips, you can use a bench grinder with a fine-grit wheel and a jig consisting of a V-shape groove in a wood block (see photo). Fit the bit in the groove so it extends beyond the edge of the block. Push the block so the bit touches the whirling wheel, and rotate the bit in the groove to sharpen the whole tip. - HANDY