With this in mind, we spent two days testing four popular drill bit sharpeners. We learned a lot by sharpening 100 dull drill bits, including carbon steel, high-speed steel, titanium-coated, and ...

I've been thinking about buying one of these but I don't know if they are just a gimmick. Also, if they genuinely work well how good do your bits need to be in the first place to be worth sharpening?

Dull drill bits are not usually a type of tool that's worth buying used, unless you can sharpen them yourself. Many companies that sharpen drill bits use precision grinding machines, but there are ...