Newly Re-designed P-Series Gearbox improves Backlash, Corrosion Resistance and Center Distance between Input and Outputs! 

Bore Reducers (Shaft Adaptors)

Replacing drive shafts can be costly, and even unnecessary if the only issue is having an incorrect shaft size. Bore reducers, also called shaft adaptors or bore adaptors, provide a solution by allowing you to increase the diameter of your shaft. These clamp-style adaptors attach to the end of a shaft to enable the connection to an incompatible bore.
Bore adaptors help resolve your shaft compatibility issues and cost significantly less than a full shaft replacement. The durable and rigid structure provides excellent holding power for use in a range of power transmission applications.

Shaft Adaptors

Ondrives.US Bore Reducers slip into the bore hole of a rotating component and reduce the bore diameter to a smaller size. Shaft couplings that have identical bore diameters on both ends are quickly and inexpensively converted to combination bore couplings. When fitted to set screw hubs, shaft diameter reducers prevent the screws from scoring the shafts and permit repeated re-positioning and easy removal of the coupling.
We offer bore adaptors in brass (smaller sizes only), aluminum, and stainless steel. The brass and aluminum bore adapters feature a feathered head that sits in the chamfer at the bore entry and prevents over-insertion. Our stainless-steel shaft adaptors are designed for set screw use and provide 25% more holding power than split-collar bore reducers. 
Read our  “How to select Shaft Couplings” White Paper to learn more about selecting the most appropriate shaft to shaft coupling adapter for your application.
Attach your shaft reducer coupling to an Ondrives.US Precision Ground Shaft, available from stock.

The Ondrives.US Advantage — Meeting all Your Shaft Adaptor Needs

  • Large range of major diameters to fit standard couplings, gears, pulleys etc.
  • Converts set screw fasteners to a split clamp device
  • Will not damage soft shafts
  • Superior holding power
  • Standard and metric shaft adapters are available from 2mm to 25mm and 0.120 inch to 1 inch
  • Simple and inexpensive solution to adjust shaft reducer sleeve's bore size

Custom Bore Reducers Manufactured to Your Exact Specifications

At Ondrives.US, we can assist with designs, modifications, prototypes, and complete production of custom drive components and gears for any application. If your project specifications require custom mechanical components, our engineering team can produce parts and components that match your drawings and meet your performance needs.

Learn More About Our Premium Bore Adaptors

ONdrives.US is an expert in design engineering drive components for high precision applications. We provide inch and metric sleeve bushings in standard sizes with custom bore reducers available by request. Browse our online selection to request a quote or contact us to discuss your unique application.