I do a lot of metalworking and I often use this on the lathe:

These are HHS chisels that you have to sharpen into the correct shape yourself if you use them on the lathe.
They are excellent for removing the last gasket residue and any burrs from the gasket surfaces.

The rods are ground perfectly flat and the edges are razor sharp but do not cut your fingers because the angle is 90 degrees.
But if you keep them flat, you will scrape away anything that shouldn't be there.