Split Point Drill sharpening

[Okapi]

I'm not totally in accordance with Tony's explanation, they are grinding wheels made as cups(or others for 45° use) for grinding on the lateral part, all makers of grinding wheels explain that you never use a wheel made for perpendicular use as a lateral use, you find it that on makers like Norton, I've only the french catalogue from Norton but you can found the same in english on the web easily.
They explain to never use on the side a wheel cup or another when the thickness is less than 10% of the diameter, then 30mm. for a 300mm. wheel etc…