Degrees of Shaftlessness

by Frank Balentine

Ever since the WIFAG OF 370 and 570 presses were successfully demonstrated in Switzerland last April, the industry has renewed its interest in shaftless presses.

Most press manufacturers make one or more shaftless models. They use at least three different approaches, however, and have differing opinions about what "shaftless" really means. A conventional press uses both horizontal and vertical drive shafts:

Conventional Press:
Both Horizontal and Vertical Drive Shafts

One version of a shaftless press employs vertical shafts but no horizontal drive shaft--in other words, it is shaftless unit to unit. Goss Graphic Systems produces such a press, which it calls "The Distributed Drive System":

Shaftless Press #1:
No Horizontal Drive Shaft

The large drive motors have been replaced with several smaller motors distributed around the press. The vertical shafts connect the units in two- or four-unit stacked configurations, enabling good color registration.

A second shaftless press has one motor for every two print couples. KBA-Motter Corp. calls this approach "Unit Drive Shaftless":

Shaftless Press #2:
One Motor Per Two Print Couples

MAN Roland also markets this type of press under the name "Direct Drive System."

A third type of shaftless press uses one motor for every print couple:

Shaftless Press #3:
One Motor Per Each Print Couple

Goss calls this "The Shaftless System," and is debugging a prototype unit in Preston, England. WIFAG's version, called "Gearless Transmission Drive" or "GTD," is in production.

The number of drive motors and their positions is very important--they help determine how easy it is to control the press and maintain precise color registration. So the next time your vendor claims to have a shaftless press, be sure to ask which one--and have them explain its pros and cons relative to other shaftless architectures.

Frank Balentine is NAA's press manager. E-mail, balef@naa.org; phone, (703) 648-1217; fax, (703) 620-4557.