As a side note, If you're needing an odd size bit for wood, Try one of them flat wood boring bits.
Measure across, grind 1 side 1/2 to the desired size, then grind the otherside to dimension.
The upper section can be ground for clearance so only the more leading edge cuts to diameter.
If you're playing with steel, a "Spade bit" (essentially the same principal) can be worked the same way.
Works good, just do the math, and copy the profile. Used this "trick" for years as a tool&die maker.