Chris and I had visited Fred many times before and he always had this contraption in the basement next to his dryer that had all these levers and knobs. Turns out this tool was to grind engine valves and he had picked it up decades ago for $50 at a garage sale.
Fred refinishing the valves with the valve grinder.
The valve on left had recently been cleaned ground smooth. The valve on the right had only been wire brushed clean.
After all the valves were ground smooth the next step was to make sure the valves sealed properly in the engine head. To do this, we applied a bit of valve grinding compound onto the valve, seated the valve in the engine and attached a drill to the end of the valve and drilled/smoothed the valve in place. Fred did the first valve below and then let us do the remaining seven.