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Agile scheduling and aggressive attitude keep camshaft shop grinding

Sept. 11, 2005
Comp Cams improves its custom camshaft-grinding operations by maintaining strong supplier relations, especially with its primary grinding-wheel manufacturer Norton Abrasives of Saint-Gobain Abrasives. Comp Cams often ...

Comp Cams improves its custom camshaft-grinding operations by maintaining strong supplier relations, especially with its primary grinding-wheel manufacturer Norton Abrasives of Saint-Gobain Abrasives.

Comp Cams often serves as a proving ground for new grinding products such as Saint-Gobain's T2 platform, an extremely aggressive cubic boron nitride (CBN) just made commercially available.

  • Comp Cams of Memphis, Tenn., manufactures automotive valve-train parts, specializing in camshafts. However, its customers are not the Big Three but Nascar teams and auto enthusiasts. Unlike automakers, these folks want camshafts tailored to fit their particular engines and applications. Unfortunately, they are often unsure of what is needed until the last minute. Then they turn up the pressure on Comp Cams to deliver within days.
  • To accommodate such last-minute orders, Comp Cams offers 24-hr grinding, but there is nothing standard about the grinding process when it comes to custom camshafts. Even though the shop uses camshaft cores close to finish-ground size, its grinders may end up finishing as many as 1,000 different cams, each with slight variations, from these cores.
  • When dealing with such hectic production, Comp Cams' camshaft R&D engineer Bill Godbold admits the shop does not know everything, so it gets a lot of help from supply partners, especially its primary grinding-wheel manufacturer Norton Abrasives of Saint-Gobain Abrasives.
  • Comp Cams uses almost every kind of grinding wheel Saint-Gobain offers, from conventional bonded wheels, to Norton SG seeded-gel (ceramic aluminum oxide), to resin-bonded, to plastic-bonded wheels and more. Sometimes, the shop is even a proving ground for new grinding-wheels, as was the case with a line of wheels released under the Universal brand name from Saint-Gobain.
  • The wheels combine a new vitreous (glass) bond system, called the T2 platform, with extremely aggressive cubic boron nitride (CBN) grains just made available to the commercial market. The bond system lets the supplier customize wheels to a user's specific application and materialtype requirements.
  • Comp Cam engineers were particularly interested in the wheels — having the potential to increase wheel life 50% to 200% as compared with standard ones — for boosting the productivity of an Okuma CNC grinder. Saint-Gobain, likewise, wanted to know how the wheels would perform at Comp Cams because the shop removes a lot more material per camshaft lobe than OEMs do.
  • In a test running about 150 Ford roller cams, the T2 wheel required less power. So much so that engineers from both companies determined it could grind twice as many parts/dress or grind twice as fast on the same number of dresses.
  • Over the years, such buyer-supplier cooperation has boosted Comp Cams' productivity. "Our number of machines hasn't increased by more than 10%," claims Godbold, "but production has jumped four-fold."
    nortonabrasives.com