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Precision Components

Stock Drive Products/Sterling Instrument a Designatronics company

Established in 1950, Stock Drive Products/Sterling Instrument (SDP/SI) is the company engineers and OEMs depend on for high-quality components, subassemblies, and engineering expertise. As a company founded and managed by engineers we understand and respond to the developing needs of our customers better than anyone. Over 100,000 components are available off-the-shelf for fast turnaround. When a standard part won’t meet your requirements we can provide alternative solutions through custom design and manufacturing. Our engineering and manufacturing teams will partner with you throughout the entire process. By providing design, development, manufacturing, assembly, and testing in one location we can ensure the end product will meet your expectations. For prototype and small to large production runs you can rely on SDP/SI.

High Volume Precision Gear Production

We manufacture precision gears, custom gearboxes, differentials, and planetary gearheads.

State-of-the-art gear production facility has increased capacity and offers new capabilities.

  • High-precision gear production 24/7
  • Faster turnaround – including gear cutting on CNC lathes for one piece flow (depending on quality (UP TO AGMA 11) and process requirements).

Stock Drive Products/Sterling Instrument, ISO 9001 + AS9100 Certified

SDP/SI designs, manufactures and produces custom and standard gears and other power transmission components. Our precision gears, gear assemblies, high-quality machined parts and molded components are used in a wide variety of product applications worldwide including aerospace, defense, military and commercial aircraft, robotics, and medical.

  • Timing Belts and Pulleys
  • Precision Gears
  • Precision Gearboxes
  • Precision Machined Components
  • Molded Components
  • Mechanical Assemblies
  • Customized Components and Assemblies
  • Contract Manufacturing

Request a Free Inch and Metric Catalog Set, more than 2,784 pages of parts, specifications and technical information.

Product Catalog

Service Catalog

Stock Drive Products & Sterling Instrument - SDP/SI is listed in these service categories:

Technical Articles

Selecting the Best Hub Fastener for a Power Transmission Application (Fastening and Joining) Gears, pulleys, couplings, shaft extenders, shaft reducers, flexible shafts and shaft accessories are critical rotating and power transmission components. They are found in assemblies for applications... (View Full Article)
Case Study: Right Angle Planetary Gearheads (Gears) At SDP/SI, our application engineers frequently deal with customers whose requirements extend beyond our standard product offering. In these cases, they are able to work together to create unique... (View Full Article)

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Stock Drive Products & Sterling Instrument - SDP/SI
Stock Drive Products & Sterling Instrument - SDP/SI
Stock Drive Products & Sterling Instrument - SDP/SI