Step drills can be turned perfectly on a lathe, but not everyone has one, and it is not profitable to pay a turner for such work. If the workshop only has emery, then the drill can be adjusted using it. However, the specificity of emery allows this to be done only by re-sharpening the cutting edges in a new way, which, however, is not difficult.
Step drill sharpening process
Sharpening on emery is carried out from a smaller diameter to a larger one. The blunt edge of the drill is applied parallel to the working surface of the abrasive disc. The shank should be slightly below the tip.
When removing metal, you must first grind off the standard smooth transition to the step, and then select it so that the cutting edge protrudes above the part of the drill located behind it. In essence, you need to achieve the same effect as with a conventional twist drill.
If you don’t have experience sharpening even ordinary drills, then it’s worth checking the operation of the drill after the first diameter to make sure that the angle is correct.When the restored part begins to drill as it should, you can sharpen the remaining worn steps by analogy.
