Grind and Sharpen A Bung Auger Reamer?

[J.]

Picked up a auger reamer at a garage sale that had been neglected for many a year. It has a pilot twist at the nose, and the blade is semicircular. How does one properly grind and sharpen these tools? My guess is that they're just big spoon bits, but I've never sharpened one of those before either.

Thanks,

J.

[bridgerfafc]

mostly by hand with a file. probably a triangular "three square" file, followed by a stone.