Spur gear

straight-toothedfor shafts

Boston Gear change gears are used primarily on machine tools to provide different cutting speeds while using a constant speed input. All Boston Gear change gears are manufactured with a double key to accept the compound steel bushings that connect two gears together, allowing them to spin on an intermediate shaft. The change gears we stock range from 20-tooth through 128-tooth gears, in one tooth increments, depending upon the diametral pitch, for a nearly infinite number of ratio possibilities. Be sure to ask for the Boston Gear compound steel bushings designed specifically for use with these gears. Many different gears with a variety of bore sizes, keyways, and setscrews are routinely in stock, but if the particular bore/keyway/setscrew combination needed is not readily available, our machining experts can alter any non-hardened gear and ship it within 24 hours. Just ask! With 20 to 128 teeth, our change gears offer an almost infinite number of ratio possibilities. A PA of 14 1/2° ensures smooth, quiet operation. These change gears are available in both steel and cast iron to suit a variety of application requirements. Compound steel bushings specifically designed for these change gears are available to maximize performance. Boston Gear's change gears are available via our Guaranteed Same Day Shipment Program to ensure timely delivery.