At Engineering Specialties, Inc. (ESI), we pride ourselves on our ability to design and build any part our customers need — no matter how unusual or complex the project. Recently, we were approached by a New England-based security products company to manufacture an aluminum-machined component.

The Problem

Unfortunately, the requested part — a 1.25 inch thick x 2.375 inch diameter pinwheel sprocket — had become virtually obsolete in recent years; there were no drawings or CAD models available for our team to reference. The customer needed 100 of these parts made with each piece part having several tolerances of +/- .002 inches; ESI was determined to deliver them.

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The Solution

Despite lacking customer-supplied drawings, ESI came prepared with an out-of-the-box solution. Our manufacturing engineer and quality engineer worked together to reverse engineer an existing sand-casted sample we were provided. Using a CMM and video inspection measurements, our team was able to produce a new 3D model which in turn could be produced via 3D printing, to confirm product function.

We gave the 3D printed prototype to the customer to check for proper form, fit, and function. Once the customer confirmed that our part would work, we moved forward with milling and turning 100 pieces from aluminum bar stock on our Mori Seiki Multi-Axis Lathe.

reverse engineering

The Result

The customer was thrilled with the quick turnaround time; our team provided the 3D printed part just two days after they came to us for help. We machined the metal pieces not long after that, using only one setup on our lathe to save the customer both money and time.

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Do you have an upcoming job that requires reverse engineering? Contact ESI today to request a quote.


Project Name & DescriptionPinwheel Sprocket
Capabilities Applied/ProcessesMulti-Axis Turning and Milling
Equipment Used to Manufacture PartMori Seiki Multi-Axis Lathe w/Live Milling
Overall Part Dimensions1.25 inch Thick x 2.375 inch Diameter
Tightest Tolerances6061-T651 Aluminum Round Bar
Material FinishClear Anodized
Industry for UseSecurity
In Process Testing/Inspection PerformedCMM Measurements and video inspection
Volume100 pcs.
Delivery/Turnaround Time3 Weeks
Delivery LocationNew England