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Configurable horizontal boring mill fits the bill

March 1, 2005
Giddings & Lewis Machine Tools Fond du Lac, Wis. glmachinetools.com

Giddings & Lewis Machine Tools
Fond du Lac, Wis.
glmachinetools.com

The Giddings & Lewis MC series horizontal boring mill boasts a built-in rotary table, pallet shuttle, and automatic toolchangers.

According to Giddings & Lewis, the modular design of its new MC series horizontal boring mills lets end users get customizable machines at standard machine prices. Shops select from a variety of table styles and sizes, headstocks, controls, attachments, and X, Y, and W-axis travel options. With the MC series, they also gain automation features such as pallet shuttles and toolchangers with their overall package.

Two models comprise the MC series: one with a 49 x 49-in. pallet and one with a 63 x 98-in. version.

The machines have a solid, rigid construction with beefy column, bed, and saddle castings. Accuracy is ensured with internal X-bracing in the column and wide way spreads that resist deflection and minimize vibration. For additional stiffness in heavy cuts, the machines' built-in rotary tables have tapered roller radial bearings and preloaded hydrostatic axial bearings.

A high-performance drive/way system employs hardenedandground preloaded roller guideways and large, zero-backlash ballscrews. The guideways minimize friction and expand capacity for large-part manufacturing. The ballscrews, which are hydraulically preloaded, enhance axis stiffness and thrust performance. In addition, rather than using a belt-driven design, the drive is geardriven, which produces high torque while reducing downtime for maintenance.

Headstock options include a twospeed version, with a 5.1-in., 60-hp spindle, and two four-speed headstocks — with a 5.1-in., 60-hp spindle or a 6.1-in., 74-hp one. All headstocks come with a live spindle that permits flexibility for drilling and tapping as well as added reach for boring.

All boring mills boast G&L's special spindle-growth compensation. This Z-axis thermal compensation software dynamically offsets spindle growth to maintain tight accuracies. Control choices include Siemens Sinumerik 840D and Fanuc 310i.

Besides the MC series, G&L has also introduced the PT series plain-table boring mills and the RT series with built-in rotary tables. The three machines replace the company's previous G, H, and PC series systems.