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  SDP/SI Engineering Capabilities

  • Capabillities

  • Engineering Stories

Complete In-House Engineering Development, Customer Service, & Special Services

Capabilities Include:

  • Engineering Development and Reverse Engineering
  • Prototypes for Design Review
  • Integration of Parts or Subassembly into a Larger System
  • Various Materials, Finishes and Surface Treatments
  • Modified Standard Components

    Modified standard components

  • Custom Gears, Gearboxes, Gearheads, and Mechanical Components
  • Custom Timing Belt and Pulley Drive Systems
  • Design Tools and 3D CAD Models

Facing a design challenge? Let SDP/SI engineers provide the custom solution to meet your specific requirements. Our engineers and manufacturing teams routinely partner with OEMs in aerospace, medical, defense, and robotic industries, providing the individualized customer support each project merits. With proven performance and unsurpassed experience our engineers are here to help!

For the best results involve SDP/SI engineers and manufacturing experts during the concept and early design stage of a project. Based on more than 70 years of experience and technical skills, our input can optimize performance, help lower costs, simplify assembly, make more compact in size, and design for manufacturability.


  • Iso 9001 + AS9100 Certified
  • Boeing BQMS Certified
  • ITAR compliant - DDTC Registered
  • R.E.A.C.H. - Compliant
  • RoHS Compliant

Our experienced, expert engineering staff can help you design the right component that's manufacturable and cost-effective. They can alter your design for changing demands and improve efficiency.
Prototype to Production

Special Services:

Send Us Your Blanks for Tooth Cutting – 3/16” to 4” OD
Many companies rely on SDP/SI for their tooth cutting needs. With the world’s most advanced manufacturing equipment we provide fast turnaround while meeting your exact specifications. Cut and deburr Fine Pitch to Medium Pitch Gears, Pulleys, Worm Gears, Bevel Gears, and Helical Gears.

  • J.I.T. Deliveries
  • Blanket Orders
  • Supply Chain Management
  • Long Term Agreements
  • Special Packaging
  • Barcoding, U.P.C. Coding
  • Customer Part Number

Ask an Engineer

We've curated scenarios that our engineers have encountered with different clientele. Here are their answers:

For more information or questions for our engineering staff, email us (at or give us a call at (800) 819-8900.

A leading medical device manufacturer approached our engineering department with a planetary gearbox which suffered a critical failure. The orthoscopic device has a planetary gear system which was shredded. This resulted from the ring gears grinding against the internal gear of the gearbox, ultimately causing lots of debris. Our engineering team also discovered a problem ... with the shafts of the ring gears, the problem caused the ring gears to be off-center while spinning along the internal gear, contributing to the failure.

Convinced we had the right approach, the company turned over the project to our engineering team to design, plan, and produce their gearboxes. Our engineers were able to provide a custom solution by modifying the original planetary gear system.

With the implementation of the re-worked gearbox which included revisions to the ring gears themselves, we provided a custom solution that gave this medical company the advantage to produce more devices at a quicker production turnaround.

As the engineer's preferred source, SDP/SI produces a wide variety of gears, including bevel gear sets, anti-backlash gears, helical gears, miter gears, worms and worm wheels, internal gears, gear racks, pinions, plastic gears, planetary gears, gearboxes, speed reducers / increasers, and differentials.

An aerospace company approached our engineering team with a unique design for a gearbox to use in an aircraft research and development application. Unfortunately, the engineers at the aerospace company did not have enough manufacturing experience and so the design was not manufacturable.

This is a common situation and something we frequently see here at SDP/SI. Sometimes, designs are over engineered which can tack on a huge cost. The engineers... at SDP/SI have practical knowledge and experience in manufacturing engineering and can streamline your design, presenting solutions to make components smaller and lighter and reduce production costs.

Our engineers were able to rework the gearbox and put it into production. Having the manufacturing know-how to get the job done, our engineering team works with customers to achieve a common goal. The result is multiple gearboxes used in research where failure is not an option.

If you can't find a standard part to meet your needs, our engineers can modify existing parts to meet your exact requirements and even create custom parts or assemblies. We partner with OEMs, manufacturing critical parts and customized subassemblies, from prototype to large production runs.

An optics device manufacturer came to us with a prototype for a mobile imaging system in need of a timing belt and pulley drive system. In the original design, the customer wanted to use a particular set of standard pulleys and reduce the bores by 2 mm. They also needed to lengthen the size... of the original timing belt used.

As a precision manufacturer, we can easily modify standard components to meet customer requirements. Modifying standard parts in lieu of creating a complete custom solution requires less scheduled production time and will be more cost-effective.

Our engineer made some recommendations and supplied the engineers at the manufacturer the CAD files for the pulleys (which is available to anyone online and for free), allowing them to complete their design.

But the customer still required assistance in choosing the correct timing belt and center distance. Did you know that we have a center distance tool on our website? It makes it simple to find the center distance measurement between two pulleys. Watch this short video to learn how to use our center distance calculator.

Once the center distance was figured out and the timing belt was chosen, the customer was able to successfully put his prototype into production and get the device rolling!

A well-known OEM producing instrumentation to measure size, shape, and surface charge on the nano level ran into a design problem and reached out to SDP/SI for help.

The OEM engineers had determined a gear train was not an acceptable option for power transmission and required a timing belt and pulley drive system... for their device. The problem was what components could reliably reach operational speeds of 14,000 rpm to 25,000 rpm.

Our engineers assist customers daily with part selection, secondary operations and design for manufacturability. In this case, working together to define all the essentials including center distance and linear velocity our engineers were able to provide a workable solution. Because of the high rpm requirement the recommendation was a thin, flat belt with grooves. At high speed the grooves would stabilize the belt and prevent movement. Hubless pulleys without flanges and a slight convex profile were chosen to complete the drive system.

With our help and close collaboration the customer successfully integrated the timing belt and pulley drive system into their prototype. We look forward to partnering with this customer and others, taking their projects from prototype into high-volume production.

To assist the engineering community SDP/SI provides a vast array of professional development and technical resources. Download design calculations and other reference material such as: comparative graphs, timing belt configurations, timing belt and pulley tooth profiles, solutions for tensioning and alignment, bearing loads, gear train design, and much more.