Improved production process
Three-M Tool and Machine Incorporated, is a small manufacturing company with 80 employees capable of doing big things. Four years ago, Three-M received an order to manufacture parts for wind turbines. Three-M relies on measuring technology from Carl Zeiss to ensure the required precision of these workpieces.
Three-M Tool and Machine Incorporated, a small manufacturing company located in Wixom, Michigan, wanted to expand their business into the growing market for wind energy. They quickly realized that when you have a tool to edge out your competition, that tool quickly becomes a key to your company’s long-term vision.
In 2008, Three-M acquired a contract to manufacture gearbox and forward housings for Clipper Windpower. Until then, they had been using an older DEA gantry system for quality inspection of other large parts. The machine’s limited speed and size meant that the new housings could not be measured assembled. Production would have slowed to three units per month instead of the required 16. The search began for a more efficient and capable measuring system.
Three-M did some research with Carl Zeiss since they had positive previous experience with them and were still using their first ZEISS system, a UMC 850, purchased in 1975. In 2005 they bought an additional CMM, a CONTURA with a VAST XT active scanning sensor. “Our first ZEISS CMM really taught us the true meaning of accuracy,” states Michael Medwid, President of Three-M Tool and Machine Incorporated.
They chose a Carl Zeiss MMZ G gantry machine in a configuration that could measure 3 meters vertically; an optimal solution for the inspection of gearbox housings standing upright. The CMM is equipped with the VAST gold probe which is capable of speeds up to 300 points per second. The VAST gold probe also allows scanning with styli up to 800 millimeters long weighing up to 600 grams. Not only did Carl Zeiss have the right machine for the job, but Three-M found them to be very competitive on cost and delivery.
Three-M invested in some of the most accurate, state-of-the-art milling machines to handle the new Clipper project. “These are some of the best milling machines in the USA, but they still are not accurate enough to hold the required tolerances on these parts. We can’t just machine the part to the print right off the milling machine,” states Michael Medwid. True position tolerances on these larger parts are about 25 microns. These new parts, typically made of cast iron, are rough-machined, undersized as three separate castings, assembled together and sent through in-process inspection, making sure screw holes are lined up, then re-machined to print as separate castings and assembled one last time for final inspection. In-process inspection is performed on every 10th part with 100 percent final inspection. The casting would warp out of shape if this process wasn’t followed
In 2010, two employees from ZF Industries visited Three-M to review their capabilities to produce gearbox housing prototypes. ZF Industries already inspects with three ZEISS CMMs in their Greenville facility so they were familiar with the systems. “After two hours they called their boss and said to quit looking because they had found their new supplier,” says Medwid. “Our ZEISS MMZ-G machine was the main reason we got that business,” claims Medwid.
In the future, Three-M is optimistic that their MMZ-G system will be able to handle parts from additional machine tools. With increased business, they are now running the CMM in two shifts. The two best things about Three-M’s experience with Carl Zeiss have been service and follow-up from the sales team. “Having the ZEISS CMM made it possible to edge out the competition and keep our big vision alive,” states Michael Medwid.
Three-M Tool and Machine Incorporated specializes in the production and precision machining markets. Three-M also manufactures new and reconfigured special machine parts for the machine tool industry in accordance with customer drawings and specifications. The company was founded in 1971 and is headquarterd in Wixom, Michigan, USA.