Machine Shop Innovation

NASA’s Glenn Research Center in Cleveland, Ohio, designs, develops and tests innovative technology to transform aviation, revolutionize space exploration and inspire new discoveries for the benefit of all. Every U.S. aircraft has NASA Glenn technology on board, making flight safer, quieter and more efficient. Every day, engineers at Glenn are conducting revolutionary aeronautics research in electrified aircraft propulsion, advanced materials and exploring next-generation supersonic and hypersonic aircraft.

Ingenuity and problem-solving are part of the culture at NASA Glenn for every employee in every job at the center, and engineering technicians Christina Rapenchuk and Jonathan Veneziano, who work in Glenn’s full-service machine shop, are no exception. In the process of manufacturing prototypes, the pair decided they needed a new way to reduce vibration during machining, and that led them to an innovative and better way to machine complex shapes by using 3D printing technology. Rapenchuk and Veneziano named their solution the Specialized Vibration Mitigation System (SVMS).

The shop’s role at NASA

The NASA Glenn Machine Shop provides the aerospace research center with a variety of manufacturing capabilities. It runs primarily as a prototype shop, creating one-offs or small quantities of parts for supporting researchers and helping them to develop their ground test articles, flight articles and prototypes for testing in the various test facilities at the center. The machine shop also creates hardware for some of those facilities, like the aircraft icing research tunnel, supersonic wind tunnels and the zero-g drop tower.

The full-service machine shop features three-, four- and five-axis CNC milling machines, CNC lathes with live tooling, surface and cylindrical grinders, as well as wire and die sinker electrical discharge machines (EDMs).

Part of the facility is dedicated to additive manufacturing and equipped with an array of 3D printing technology, including a wide range of engineering photopolymers, plastic fused deposition modeling printers, and stereolithography apparatus printers — a type of resin 3D printer that uses a laser to cure liquid photopolymer resin layer by layer. The additive manufacturing shop is also equipped with a metal printer, which can print 17-4 PH stainless steel, copper and Inconel 625 nickel chromium.

In addition, the shop is capable of micromachining lenses, mirrors and other hardware that require high-precision, high-accuracy and/ or high-surface finishes.

The challenge of vibration

When machining thin-walled features on parts, the lack of rigidity introduces vibration into the system. Vibration, in combination with cutting forces causes chatter, which can lead to poor surface quality and out-of-tolerance features, as well as being detrimental to tool life.

The use of clay as a stabilizer is the traditional way to combat vibration and chatter while machining parts. Clay is dense and sturdy enough to add support to thinwalled features and can withstand cutting conditions and fluids. However, clay is a dirty material that can be hard to clean from parts and is time-consuming to implement.