2017 Makino a71nx CNC Horizontal Machining Center

The Makino a71nx is a 50-taper, four-axis horizontal machining center built for the unattended, high-removal production work that separates a true HMC cell from a vertical mill with a rotary table bolted to it. This 2017 machine carries travels of 35.4 x 35.4 x 40.2 inches over a 500 x 500 mm (19.7 x 19.7 inch) pallet, takes workpieces up to 35.4 inches in diameter by 39.4 inches long at loads to 2,200 lbs, and turns a 10,000 RPM CAT50 spindle rated 49.6 HP and 378 ft-lbs of duty-rated torque - the torque curve that lets a 50-taper machine hog steel and stainless rather than just spin fast. Rapids run 1,968 ipm in X and Y and 2,362 ipm in Z with cutting feed to 1,968 ipm, and the 60-position magazine changes tool-to-tool in 1.7 seconds and chip-to-chip in 3.6 seconds while accepting tools up to 11.8 inches in diameter. A 360-degree direct-drive NC rotary table handles B-axis positioning for multi-face work in a single setup, and the machine runs on 460 VAC three-phase 60 Hz service at 52.0 kVA.

Set against the Makino a71 it replaced, the a71nx is a generational redesign rather than a refresh. The nx platform reworked the structure and drive train around faster non-cut motion - 1,968 ipm rapids in X and Y, 2,362 ipm in Z, a 1.7-second tool-to-tool change, 3.6-second chip-to-chip, and a 60-position magazine in the standard build - all of it aimed at pulling dead time out of the cycle instead of chasing a headline spindle speed. Under the pallet sits a 360-degree direct-drive NC rotary table, so B-axis moves are fast and repeatable instead of being the slowest thing in the program. The practical result is a machine that puts a larger share of every cycle into actual cutting and holds size through long unattended runs, which is exactly what a shop buys a 50-taper horizontal to do. Choosing this generation over an older a71 means the spindle, the pallet automation, and the tool-change speeds are all current-generation rather than the next thing on the replacement list.