Move Over, Makeready

Quick-change can happen on-line, off-line, or perhaps even somewhere in between.

By Susan Friedman

Clark Kent may have consistently favored an "off-line" retreat into a telephone booth for his legendary Superman "changeover," but quick-change makeready systems for today's presses are a little more fickle.

A supplier's idea of the fastest, most cost-effective job-changeover set-up can range from a completely self-contained system that never leaves the press, to a completely removable system, to one that can move a job off-line, but not away from the immediate printing area. Here's a look at several design rationales.

The inside story

Propheteer's standard approach to quick-change—an open print head that does not slide out or leave the press—is about as on-line as one can get. All components are individually quick-change, without tooling, and can be removed by lifting or via swing clamps, explains V.P. Mike Polkinghorne.

For a normal, water-based work environment, Polkinghorne believes the open print head approach is the most effective because room to work is built right into the design.

Comco's ProGlide, a sliding drawer technology first unveiled at CMM '97, was initially introduced as an option, but its popularity has led Comco to make the system standard on all Flexo-pack and Commander press designs, creating a line of presses rechristened ProGlide MSP (Multiple Substrate Printing), reports Marketing Manager Chris Faust.

The system features shuttle deck printing stations which house the ink pan, meter roller, anilox roll, doctor blade, and printing cylinder on linear bearings. One of the keys to ProGlide's appeal is that the stations slide out, but not off, Faust stresses, preventing wear and tear that can result from repeated removal and replacement of the print head. Because a self-contained drawer system harbors little need for extra hardware, it conserves valuable floor space and staff, he adds. To accommodate wider press widths, the system's height has been ergonomically adjusted to eliminate the need for overhead hoists or cranes.

A 10- or 11-color press with ProGlide stations may cost about 4 percent more than comparable presses, but operators can knock more than 50 percent off makeready time with the system, Faust notes.

Outer...limits?

Frank Laughlin, V.P. sales and marketing for Chromas Technologies, sees the drawer approach as "pretty much standard." Chromas' quick-change drawer system allows on-press changeovers as fast as three minutes per print station, for 7 1/2" to 26 1/2" press widths.

Laughlin believes the removable cartridge is the next logical step in quick-change's evolution, citing Chromas' Instant Change Technology (ICT). Its inking system, pan, doctor blade, and anilox roll are mounted on a cassette that can be slid on to an off-line makeready cart which also carries plate cylinders, ink pumps, and gauging tools. A new job, already set up on the cart, can be slid on-press as the old one is removed. Cartridges can also accommodate dies and hot stamping units, while keeping total changeover time to 10 minutes.

ICT is currently offered on 10" to 16" Chromas presses, but Laughlin says the capability will be available in widths to 26 1/2" by the third quarter of this year. Package printers can get their feet wet with "Level 1" ICT—a drawer design, and then add on "Level 2"—the cartridge design later.

Laughlin emphasizes mobility as critical to maximizing quick-change cartridge technology. Chromas' ICT cart can be moved to another press, or a more remote off-line location, allowing increased press uptime, he explains.

Propheteer has offered a removable cartridge design on its Ultrapress for UV printing since 1992, with a redesigned version launched last year. Polkinghorne says the company's cartridge approach is based on the advantages of UV printing; UV ink stability eliminates the need to continuously turn the anilox roll, thereby eradicating the need for an extra makeready table.

Instead, Polkinghorne elaborates, cassettes can be removed to a regular bench. UV ink properties permit an operator to ink up all of the cassettes at the beginning of the day, and/or wait to clean all of them together at the end of the day.

On Taiyo Kikai presses, says Product Manager James Willingham, quick-change does not involve a cartridge, but it does stress the simplifying effects of moving job components away from the press.

Taiyo Kikai developed a quick-change design with a roll-away rack for its first foray into narrower web-width presses, a product line launched in January. New TLF 250 flexo presses in 10" and 15 3/4" widths feature the system, which enables anilox rolls and print cylinders to be carted off-line for storage.

The inking system slides out at the turn of an electrical switch and the pull of a latch, enabling the anilox roller to be changed on the front side of the unit, and the ink pan to be changed on the back side.

In press stop mode, Willingham adds, the plate cylinder contact with the anilox roller and impression cylinder is removed by an auto on/off air cylinder. He contends, at these narrower widths, that grasping the plate cylinder, flipping a switch and lifting the cylinder from the unit is actually faster than using a sliding motion for changes.

Yet another quick-change philosophy argues strongly for moving makeready operations off-line, but balks at taking them too far afield.

The Super Quick Change (SQC) Makeready System from Mark Andy debuted at Labelexpo Europe '97 as a retrofittable extension of the company's QC sliding drawer approach. "In most cases, the sliding drawer technology is sufficient," says Brace Cooper, V.P. sales and marketing, "but the SQC is ideal in a very short-run environment where job turnaround is critical."

The SQC system features inking cassettes that slide onto a stationary, off-line makeready workstation aligned to the press. Available in modules built much like a press, SQC includes an anilox roll cleaning system and is said to reduce make-ready time by 75 percent, allowing color changes in 30 seconds.

Cooper positions the stationary table as more versatile than a movable cart system—precisely because it stays in one spot. "All printers have a work bench set up with the press," he states. "The SQC system is multifunctional—used for changing over the print stations and as a work bench. There are also storage areas on the top and bottom of the work station."

Cart-type systems, he maintains, require room along the press for moving the cart up and down during change-overs, and printers are left still needing space for a work bench.

Beyond the drawer or the table

A forthcoming quick-change system for the wide-web segment reflects a continued focus on moving press components easily, while also tackling time-consuming color matching practices.

In the next month or two, package printers can expect to see a "machine-paced changeover" offered with Paper Converting Machine Company (PCMC)'s next-generation flexo press. According to Marketing Strategist Tom Jacques, the approach is designed to compensate for varying operator energy and enthusiasm that can sap changeover consistency, and enables a physical changeover of more than 10 color stations in less than 30 minutes.

Changeover time in wide-web flexography is really comprised of three main areas: press make-ready, physical component changeover and color matching, Jacques points out. Clean-up systems and various carts and fixtures assist with make-ready, while physical changeover is largely a function of design, but color matching has been a real drag on industry efficiency, he adds. PCMC's new system incorporates the means to get color matching set up while the press is running, saving as much as 50 percent of makeready time, he reports.

Taiyo's Willingham contends that at narrower widths, grasping the plate cylinder, flipping a switch and lifting the cylinder from the unit is actually faster than using a sliding motion for changes.