President Dave Moellering of Moeller Manufacturing says the shop's three Anca CNC punch grinders each produce 10 to 20 typical part shapes in volumes up to 15,000 annually.
By switching to CNC grinders, Moeller Manufacturing Co. of Plymouth, Mich., now produces and delivers virtually any punch from solid within three days of a customer order. The shop, which manufactures punches, die buttons, retainers, and die details for the tool-and-die and metal-stamping industries, runs three Anca PGX CNC punch-grinding machines that each produce over 15,000 parts annually.
Originally, manual surface grinding would produce a complete punch in 1 to 1.5 hr, and cam-driven machines did it in 15 min. But the CNC grinders with 30-in. CBN wheels cut the time to between 8 and 10 min. For making punches, says Dave Moellering, president of Moeller, the Anca grinders eliminate setup time required for cam-driven machines as well as the investment in cam development and machining.
The PGX grinders handle round, eccentric, and step HSS punches up to 6 in. and weighing as much as 550 lb. A 30- hp/ 22- kW spindle drive on each machine powers the abrasive wheel to rapidly generate punch surfaces within 0.0002-in. parallelism. The machines maintain a constant surface speed, and their dynamically balanced wheel spindles are programmable through the CNC for speeds from 200 to 3,000 rpm or constant surface speeds. They accommodate both conventional and vitrified CBN wheels, which reduce tool stress and grinding temperatures for high stock removal.
In addition to the machines' grinding speeds, software streamlines Moeller's order processing. An off-line CAD/CAM software suite lets the shop input punch-design data and complete a new program in less than 20 min. "The software makes programming even the most complex punches easy," adds Moellering, "because of its easy-to-use graphical user interface, which presents a shape menu for standard tasks and a 2D geometry editor for more complex tools."
Farmington Hills, Mich.