These are ground on a Deckel or Alexandra single lip grinder, often called a Universal tool and Cutter grinder which they are NOT.

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Because the engraving cutters are made of micrograin carbide they have to be ground with a diamond wheel to get the finish needed.
A simple jig could be made from a spin indexer and a small motor with a diamond wheel acting on a pivot so the wheel can pass the cutter as it swings at the correct angle.

Sharpening these is a simple job once setup.
I save mine and when i get about 5 or 6 chipped or blunt ones I do them all in one go, takes a couple of minutes per cutter tops.

Because these are actually made from powder it stands to sense that the actual tip is very fragile and it pays to take a fine diamond file and take a swipe at the end to purposely put a flat on it before it chips it off.

It's very, very easy to chip the tip on one of these, with a grinder it's very easy to grind them up or even grind a complete new one from round stock out of HSS, doesn't last as long as carbide as regards wear but is far more forgiving on fine work in soft materials.