Metaldyne presets, heat shrinks, cools, and measures its tools in fully automatic cycles on a Redomatic heatshrink/ presetter system.
The Redomatic system sets Metaldyne's required shrinkfit-tool lengths to within ±10 µ.
Metaldyne's Edon, Ohio, plant manufactures automotive steering knuckles, probably one of the most complex parts on cars. These components present a machining challenge because they require milling, drilling, and boring a variety of holes and surfaces.
To meet steering-knuckle-production volumes and quality requirements, Metaldyne uses twin-spindle machining centers. Each spindle performs mirror-image operations, so tooling must match to within 20 µ, which is why the shop employs shrinkfit HSK 100 and 80 toolholders.
However, preparing these tools on a shrinkfit toolchanging machine and separate presetter often proved time consuming and inconsistent when it came to setting accuracies. In addition, the separate units couldn't automatically write tool data to chips embedded in Metaldyne's holders. The solution was a Redomatic heatshrink tool presetter/measuring machine system.
The shop presets, heat shrinks, cools, and measures its tools on one unit in fully automatic cycles. The system delivers 10 kW for shrinkfitting 0.120 to 1.260-in. shank diameters and lengths to 23.622 in. with 5 to 10-sec heating times. Cooling takes 30 sec or less using cooling adaptors, say Metaldyne plant engineers.
The company's Redomatic incorporates a Saturn 2 vision system that automates tool measuring and inspection, a 3-axis CNC vertical tool presetter, and measuring machine with a Z-axis that handles up to 23.58-in. lengths and 15.72-in. diameters. Two CNC-driven linear slides (vertical and horizontal) position the system's optic carrier, and CNC spindle rotation permits focusing on tools.
The outstanding benefit for Metaldyne, according to Chris Filoso, manufacturing engineer at the company, is that it sets any shrinkfit tool's required length within ±10 µ, which is important because steering-knuckle d.o.c.s are critical.
The system's induction-heating coil automatically positions over holders and heats them for loading tools. A CNC-driven tool-length stop ensures correct tool positions in holders (for instance, tool tip to gage line). Operators select one of five cooling adaptors and position it over the holder. The system again checks the tool and transfers measuring results to the tool-identification chip.
"The procedure takes about two min," says Filoso, "and we store any correction values for use in the next shrink-clamping process."
The Redomatic also measures nonshrinkfit tools faster than Metaldyne's previous method. For instance, the shop inspected a 10-insert tool one insert at a time, and operators had to decide how much to adjust each. The Redomatic automatically checks each insert and indicates how much to adjust them.
Within the system, the shop also tracks tool life for each tool on its various machining centers. Chips on toolholders identify the tool, its offsets, and cycle times for each tool and insert. Having such data lets Metaldyne maximize tool life while maintaining machining quality.
Ann Arbor, Mich.