forstner bits

I picked up a number of OLD forstner bits (about 50) at a yard sale. Some of them have been rode hard and put away wet.
Can anyone point me to a procedure for sharpening these that will preserve the geometry?

TIA

robotic regards,

Tom
= = = = =
"Know where you're going or you'll go nowhere."
- - Burda Vandeborne

Hello Toymaker,

Take a look at this vid https://www.youtube.com/watch?v=HDEyDKj2R9U

Hope this helps!