Key details to know
Headstock spindle size and TPI: Knowing these specifications is important when you want to add a four-jaw chuck to your lathe. Most four-jaw chucks require an adapter to mount to the lathe, and these must match the headstock spindle. Common headstock spindle sizes are 3/4" x 16TPI, 1" x 8TPI and 1-1/4" x 8TPI.
Swing over the bed: This is twice the distance from the tip of the drive center down to the lathe bed. It tells you the maximum diameter that can be turned on that lathe.
Distance between centers: This is the distance between the drive or spur center on the headstock and the rotating center in the tailstock when the tailstock has been moved out as far as it will safely go. It tells you the maximum length of stock that can be turned on that lathe.
Speed: What’s the lathe’s range of speeds? Is it a fixed-speed or variable-speed lathe?