A friend bought a 10" Rockwell lathe but discovered that two of the change gears, a 16 tooth and it's mating 32 tooth gear were completely stripped. A previous owner must have had a heck of a crash. My gage says these are 20DP gears. I've got the equipment to cut gears and even have a 20DP cutter that will cut the 16 tooth gear. We'll have to buy the involute cutter for the 32 tooth gear. My cutter is unmarked, and since gears with a 20º pressure angle are more common than those with a 14.5º pressure angle, I ASSUME my cutter has a 20º pressure angle. I've read that some older lathes (not necessarily Rockwell) have change gears with a 14.5º pressure angle. Does anybody know what the pressure angle is of the change gears in a 10" Rockwell lathe? How do you tell the difference between gears with a 20º pressure angle and those with a 14.5º pressure angle?