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Boston Gear® GD72A
Boston Gear®

Boston Gear® GD72A

Boston Gear®


Boston GearĀ® GD72A GD Series Web with Lightning Hole Change Gear With Double Keyway, 12 Pitch, 14.5 deg Angle, 3/4 in Face W, 72 Teeth, 6 in Pitch Dia, 1 in Bore Dia, Cast Iron

  • Item#: GD72A
  • Mfr#: GD72A
  • UPC: 781711111888
  • 14.5 deg pressure angle will not operate with 20 deg spurs
  • More cost effective, quieter running and corrosion resistant operation
  • Higher contact ratio for a smoother, quieter operation with 14.5 deg pressure angle
  • Min. Order Qty: 1
  • Qty. Interval: 1
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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 diametrical 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.

Boston Gear® Change Gear With Double Keyway, Web with Lightning Hole, Series: GD Series, 1 in Bore Dia, 6.17 in Outside Dia, 72 Teeth, 12 Diametral Pitch, 6 in, 3/4 in Face Width, 2.19 in Hub Dia, 14.5 deg Pressure Angle, 1/4 x 1/8 in Keyway, Cast Iron


Hub Diameter      :      2.19 in
Keyway Size      :      1/4 x 1/8 in
Outside Diameter      :      6.17 in
Series      :      GD Series
Type      :      Web with Lightning Hole
Diametral Pitch      :      12
Pressure Angle      :      14.5 deg
Face Width      :      3/4 in
Number of Teeth      :      72
Pitch Diameter      :      6 in
Bore Diameter      :      1 in
Material      :      Cast Iron


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