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The Revolution Blog

This is our “Ted Talk" on flawless CNC Machining

Thursday, Sep 30, 2021

Drilling the Zerk in special fixture

If we had to give a Ted Talk on efficiency, we would reference a recent special order as THE case study. Our team was only able to accomplish this through dedication, attention to detail and countless early/late hours. Here’s how we would talk about the project…while wearing those unmistakable Ted headset mics, of course.

Why was this special order so extra-ordinary?

For starters, it was exceptionally large—approximately 400 custom single flange track wheels. To put it in perspective, a typical Hamilton order of non-standard wheels usually runs between 10 and 25 parts. Additionally, most special orders require 8-inch or smaller wheels. The wheels for this order are 14 inches in diameter. So our team really needed to plan carefully and streamline the machining process as much as possible.

What pre-planning was involved to minimize waste and maximize efficiencies?

First off, we used CAD/CAM software to create the CNC programs for the wheel. Then we spent a lot of time troubleshooting to define how many wheels we could machine per insert without risking terminal failure. The team also created and customized a few special parts to keep production moving:

Getting ready to press in bearings
  1. We created a special fixture to assist loading such a large/heavy wheel into the CNC Lathe safely
  2. We also created a custom-designed fixture that allowed us to accurately drill a hole for the grease fitting and, in turn, eliminate the need for a separate milling operation
  3. Finally, we re-designed a hydraulic press to accommodate the wheel while pressing bearings in

How did it all turn out?

We had a tolerance of 0.003, had zero scrap, and perfect quality (0.003 is the dimeter of a human hair).

A special shout-out to the magician in these photos, one of our best Cell Operators, Yonus Tesfay. If it wasn’t for Yonus’ dedication and work ethic, we would not be in the favorable position that we are in. For the last four months, he’s been working 10- to 12-hour days machining the wheels.

(Drop the mic)

Part ready to load with special fixture

Single Flange Track Wheels

  • Capacity: Load capacity is 18,000 lbs. when used on 60 lb. ASCE rail at speeds of 2 MPH or less, intermittent operation only, with no shock or impact loads, and no adverse environmental conditions
  • Material: 1045 Forged Steel
  • Diameter: A-14"
  • Face Width: S - 2-5/8"
  • Flange Diameter: P - 16"
  • Face and Flange Width: K - 3-1/2"
  • Hub Length: H - 3-3/4"
  • Hub Diameters: M & N - 6" diameter x 1/8" long
  • Bore: Wheel is equipped with tapered bearings and bearing seals for a 1-1/2" axle.
  • Finish: Clear coat enamel
  • Other: Wheel is equipped with a grease fitting, which is located in a recess machined into the side of the wheel

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