Stem Pinions

Open Gearing


Stem Pinions

Boston Gear Stem Pinion

Boston Gear's stem pinions feature small numbers of teeth that are cut integral to the steel shaft. Using a special, enlarged pitch diameter minimizes the undercutting of the teeth. When run with standard stock spur gears, stem pinions increase the ratios normally found in spur gear drives.

Please note: Stem pinions are not intended to be operated with each other, with internal gears, or with eleven-tooth spur gears. They will, however, run satisfactorily with all other standard 14 1/2° PA spur 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!

    • Boston Gear's stem pinions have a smaller number of teeth than standard spur gears.
    • Teeth are cut integral to steel shaft for greater dependability.
    • Stem pinions facilitate higher gear ratios than are possible with spur gear drives for improved operation.
    • Boston Stem Pinions can be readily used with standard 14 1/2° PA spur gears.
    • Available from 20 DP to 6DP (Diametral Pitch)
    Boston Gear
    701 Carrier Dr.
    Charlotte, NC 28216
    Web: CONTACT
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