CELL SHIFTS HARLEY PARTS INTO HIGH PRODUCTION
A production cell of three Makino A55E machining centers managed by a Makino Machining Complex and model A3 cell controller produces shifter forks for Harley-Davidson at Anderson Machining Service.
Harley-Davidson isn’t alone in applying the most capable and productive processes to meet requirements of high-quality, high volume parts at a reasonable price. It demands the same from its contracted shops, such as Anderson Machining Service (AMS) Inc.
The Wisconsin-based company produces shifter forks for Harley using a production cell compromised of three Makino A55E machining centers managed by a Makino Machining Complex (MMC) and model A3 cell controller. Automating with the MMC lets two operators manage the three machining centers during each shift, as opposed to four needed to operate the shop’s previous HMCs. the cell also increases daily shifter-fork-set production by 34%.
With the MMC, AMS works six pallets among the three HMCs. Between cycles, each pallet transports to a work cell where an operator removes, rotates, and loads shifter forks onto a tombstone. The pallet then moves to an available machining center.
When AMS was first awarded the shifter-fork project, it used four high-speed CNC HMCs, which required 12 operators for around-the-clock, five-days-a-week production. The process was effective, but there was room for improvements in efficiency and production costs.
A lot of that improvement came as a result of the A55E’s indexing speed. AMS’s previous HMCs took 6 to 7 sec to index and reclamp at 90 degrees - the Makinos do it in less than a second.
The A55Es sport 14,000-rpm spindles and repeatable accuracies as tight as 0.000060 in. But despite these capabilities, AMS did not gain production by changing cutting parameters.
The company had run pallets with tow-sided fixtures holding sets of three shifter forks on each side. Because the A55Es machine faster, the shop consolidates its fixtures to run twice as many parts per pallet.
The previous process took 5 min and 35 sec to machine the two-sided fixture, whereas the Makinos complete the same fixture in 4 min. Since the Makinos do a four-sided fixture in 6 min and 45 sec, AMS can increase the amount of parts per pallet by 100%, while increasing machine time per pallet by only 21%.
Reprinted by permission of American Machinist Magazine