Mining Component for Rotor Structure

We specialize in manufacturing difficult custom parts at Trade Tech, Inc., including projects that are beyond the capabilities of our competition. These include parts with complex geometries that require multiple machining processes. Our history of close tolerance work and our strong reputation in the industry lead a customer in the mining industry to contact us regarding the project illustrated here. This client had a steady-but-infrequent need for a component, which was to be used for a rotor structure of a large electric motor employed in mining vehicles. The client had a long history of difficulty in manufacturing or sub-contracting this part; however, we were able to fill in this niche by providing high quality, accurate, and on-time custom fabrication and machining services that met their exact specifications.

This part was fabricated from alloy steel and required multiple manufacturing processes to complete. This component’s fabricated body needed to undergo rough machining and pre-machining without distortion. To ensure success, the piece needed precision machining completed at each work center, including our horizontal machining center (HMC) and CNC lathe. The piece also contained multiple inside and outside diameters, all of which needed to maintain tight tolerances over keyways. Our highly qualified machinists performed all of these complementary operations on our state-of-the-art equipment, and were able to complete the work at tight tolerances and exactly to our customer’s specifications. The final product weighed 524 lbs. and was completed to tightest tolerances of ±0.0005″.

Our customer was very pleased with our work and awarded us the position of premier supplier status for these and several other parts. When ordered, we complete one to four custom units and deliver them to our customer’s Wisconsin location within a turnaround time of just six weeks. To find out more about this project, please see the following table or contact us directly.

Spider Specifications

Product Name


Production Description

Used for a rotor structure of a motor

Capabilities Applied / Processes

Manual Turning, CNC Turning, CNC Milling, AWS D1.1 Welding, CMM Inspection

Stress Relieve, Sandblast

Equipment Used to Manufacture Part

Manual Horizontal Lathes, CNC Horizontal Lathes, Welding FCAW, Horizontal Haas EC1600, Vertical Mill

Overall Weight

524 lbs

Tightest Tolerances (±)


Material Used

Low Alloy Steel

Material Finish

63 √ Ra µ 63

In Process Testing / Inspection Performed

CMM Inspection

Industry For Use



1 – 4 Units per Run

Delivery/Turnaround Time

6 Weeks

Delivery Location

Wisconsin, US

Standards Met

Customer Supplied Print, 2D CAD Drawing