Published 12/14/2004

Italian Offerings In Unattended Machining

From BI-MU 2004, here are a few examples of Italian companies addressing the need for unattended production and single-setup machining.

Peter Zelinski

Editor-in-Chief, Additive Manufacturing

The mc2 (top) has two pallets in the work zone with two active spindles per pallet. A machining center from Emmeotto (middle) has both horizontal and vertical spindles. The Zero 2 (bottom) holds the workpiece between opposing stops that are able to rotate the work.

Two important destinations in Milan: the Duomo cathedral and BI-MU, the Italian machine tool show. Think of them as two different extremes in the attitude toward labor cost and leadtime.

The Proflex (top) uses two, three or four grinding spindles to perform operations including OD grinding, ID grinding and grinding grooves in a single setup. Clamping mounts from Gerardi (middle) allow opposing screws to fasten to the table and the bottom of the part. The Jet Five (bottom) performs five-axis machining of very large parts.

For a look at what manual labor can accomplish, see the Duomo of Milan, Italy. This cathedral, 500 feet long and 350 feet high, is adorned with about 2,000 different statues. Construction took 500 years. To say the least, attitudes toward manual labor (not to mention leadtimes) have changed somewhat since then.

The modern attitude toward labor cost was evident at this year’s BI-MU, Italy’s biennial machine tool show, which also makes its home in Milan.

BI-MU is big. It was the world’s second biggest show for metalworking technology this year. To try to characterize the entire show in one article—13 halls, 4,000 machines on display—would do the show an injustice. But just one interesting facet of the show was the ingenuity that some Italian companies have applied to unattended machining, particularly the ability to machine a part complete in a single setup.

One impressive machine for unattended production was the new “mc2” machining center from Riello Sistemi. Actually two machining centers mated together, the machine includes two sets of two spindles each, for four active spindles. The two sets of twin spindles work on two different pallets, and a four-position pallet changer allows two pallets to be loaded while two pallets are in the work zone. The twin spindles can machine simultaneously, or one can cut while the other speeds back to the toolchanger. Each spindle has its own set of 20 tools, so there are four separate tool magazines included in the machine.

Other twin-spindle machining center variations aimed at even greater effectiveness for single-setup machining. Emmeotto exhibited a machining center with one horizontal spindle and one vertical spindle, allowing the machine to reach five faces of the part. Picchi’s “Zero 2” machining center includes no table, but instead pins the part between two opposing, rotating stops that hold the part like bookends. The twin spindles on this machine allow machining and tool change to occur at the same time.

Grinding machines on display also consolidated setups. Tacchella Macchine showed its “Proflex” grinder, which is not so much a single machine as a concept in grinding. Proflex machines are available with two, three or four spindles in order to perform a range of grinding operations in one cycle. Particular grinding heads with particular arrangements of spindles are chosen according to the needs of the end user’s application.

But other solutions for single-setup machining are not so complex. Gerardi showed clamping mounts for machining centers that make it possible to hold a part entirely from the bottom face, leaving the other faces of the part unobstructed. (The mounts are not yet available for the U.S. market, but the company says they will be soon.)

Then there are the parts that are so big that most of the machining simply has to be performed in one setup. One of the largest machines on display at BI-MU was exhibited by MCM. A company that has been seen at the United States’ main machine tool show, MCM commands a more striking presence here. It showed a representation of its “Jet Five” machine, which uses 2 meters of Y-axis travel and up to 19 meters of X-axis travel to perform five-axis machining of aircraft parts and other big workpieces in titanium, Inconel, aluminum and steel.