I had some FE heads with some pretty decent burrs on the valve tips. Instead of slowly turning the valves by hand to file the burrs off, I grabbed an old valve lapping stick and chucked it up in the drill to spin the valves. It went really quickly, and I was able to easily take just the burrs off without digging into the stem diameter.
Jake Sampson
Sampson Race Engines
Inver Grove Heights, MN