One of the reasons the aerospace industry is so often talked about in the trade journals is because it lives on the edge of new manufacturing technology development. In fact, it drives it. Pushes it. Invents it.
And it’s an honor for us to work with the world’s brightest minds, creating this industry’s machining solutions surrounding goals that are still evolving, such as the hotter hydrogen jet engine, the shorter-range lithium powered aircraft, and ever-lighter bodies. Yes, it’s difficult work, but it’s exhilarating, too. Our imaginations are sparked by jets, rockets, helicopters, telescopes, and rovers. Metal Fabrication
We get to be part of the development teams to resolve how to cut new materials for these engineering marvels—some hard, some fibrous, and all extreme-temperature resistant. Like any machining puzzle, it all comes down to that cutting tool/workpiece point, yet there are dozens upon dozens of arts and sciences devoted to everything leading to and supporting that interface.
For example, the art of hand scraping the mating surfaces of our precision machine tools takes years to perfect. That’s an important facet, but also a tiny fragment of all that comes into play when developing a machining solution for something that doesn’t even exist yet. Just think of all the others, involving part and machine design, fixturing strategies, spindles, software coding, control electronics, automation, process considerations, feeds, speeds, rpm, and so much more—all of course with long-term reliability built in. It’s mind boggling!
One example with wide appeal is our company’s involvement with the James Webb Space Telescope. We were involved from the very beginning of the project, when it makes the most sense to enlist a machine tool partner for the best and most cost-effective outcome. The eight HMCs we built to machine the 18 beryllium mirror segments combined a massive, robust structure with the ability to position within a few microns anywhere within the entire machining envelope, which was 2,000 x 1,500 x 980 mm (X, Y, and Z axes). It was like the tank met the violin.
To accommodate these large and heavy workpieces, each machine column weighed 11 tons and each bed was 20 tons. Each beryllium billet began at 700 lbs. [317.5 kg], then was machined down to 28 lbs. [12.7 kg]. The machines needed to position and travel in a very specific manner to provide consistent cutting conditions.
The toolpaths and how the servos controlled the toolpaths were key to successfully cutting each of the 18 mirror segments. Machining accuracy began from the ground up. The machines were mounted on concrete pads that were 1 meter thick. Each pad was packed in a bed of sand to isolate the machine from surrounding equipment, and each machine was anchored to its pad using 27 anchor plates and 108 bolts.
So, not only was each individual machine highly accurate and precise, but what was really unique was that all eight machines were matched to each other—they were the exact same geometry in all the vital locations in that volumetric space. For instance, if the customer unloaded a mirror on one machine and reloaded it on another on the same locators, initiated the program, and moved it to its starting point, it was in exactly the right place as all the other eight machines. Imagine how challenging that was to accomplish.
Yet how exhilarating it was to see those first images being relayed last summer!
Automatic Welding That’s the wonder of the aerospace industry —challenging design, engineering, and building requirements, yes. Yet, all wrapped in inspiration, innovation, and imagination that will continue far into the future.