Granite Machine Base Eliminates Vibrations

Several years ago, Spectralytics, a manufacturer of medical devices, precision components and specialized machinery, encountered a persistent vibration problem with the bases on some of their precision machines. Caused by outside sources, the vibration made it impossible to achieve acceptable accuracy in their finished product.

After researching several solutions, Spectralytics decided to learn more about the possibilities of incorporating the well-known vibration-dampening attributes of granite into their machine bases, hoping that granite would help them obtain the extremely-high standard of accuracy they needed.

Because they had no previous experience with granite, Spectralytics needed outside expertise, so they contacted Tru-Stone Technologies, a division of The L.S. Starrett Co., located in nearby Waite Park, MN.

Within two days of the initial contact with Tru-Stone, the two companies engaged in extensive design consultation followed by a preliminary quotation from Tru-Stone. After this initial design pass, the team at Spectralytics toured the Tru-Stone facility and learned more about the company's capabilities while discovering appealing options for future designs.

The CNC Excimer laser machine uses a granite base to stabilize beam delivery.

After careful consideration and work with Tru-Stone engineers to finalize specifications, Spectralytics became convinced that the granite solution proposed by Tru-Stone offered the best potential for better vibration dampening, and more importantly, the higher accuracy that they required. These factors, combined with the good working relationship between the companies and reasonable lead times, convinced Spectralytics to implement the custom granite solution offered by Tru-Stone.

The result for Spectralytics was elimination of the vibration problem and consistent accuracy in their finished products. Spectralytics's newly designed CNC Excimer laser machine uses a granite base to stabilize the beam delivery. This is a 7-axis machine that performs precision excimer laser micro machining. The process involves a tube that rotates and advances while being processed with an ever-moving laser focus head. With the granite base, machining on parts can actually be performed at the molecular level.

To date, Tru-Stone has produced granite for Spectralytics ranging from a 24"x36" precision base with fourteen inserts, to a large 2,000 lb multi-component contoured granite assembly. Now, all of the new base designs utilize granite.