High-flying trick to determine lathe speeds

My lathe doesn't have a speed readout, making it difficult to follow turning plans. But I figured out a way to pinpoint my lathe's speeds easily, using a borrowed optical tachometer—commonly used by remote-control airplane enthusiasts to determine prop speed. To make your lathe's faceplate simulate a propeller, attach a white piece of paper to it and mark a ¹⁄₂ "-wide black stripe across the diameter. Turn on your lathe and adjust the speed, applying labels marked with actual speeds so you'll be able to select the proper one for each job.
—Kevin Gustafson, South Rockwood, Mich.