Q: Must we have a pilot line?

David Roisum, Ph.D., Consulting Technical Editor 920/725-7671 DRroisum@aol.com www.roisum.com -- Converting Magazine, 3/1/2001

A: In previous lives, I was a manager of an R & D lab for a large machine builder, built a pilot lab for a university, and was a senior R & D engineer for a Fortune 100 web maker. Having been around pilot machinery for a long time, I can say that from experience that it represents a two-edged sword. Costs and benefits must be carefully considered so that the company achieves a monetary payback. Often that payback is in the form of improved product designs that can maintain market share or even create new markets. However, process efficiencies might be made on production machinery that were more easily learned from experiences on pilot machinery.

The first issue with pilot machinery is design philosophy. Too many people make the mistake of designing the pilot machine to look like their production machine, only scaled down in length, width or speed. This is extraordinarily and unnecessarily limiting. Sometimes the essence of a problem can be captured with equipment far simpler than production machinery.

For example, I began pioneering research in tissue winding by 'winding' the rolls by hand on the floor. The physics of my hand was identical for that purpose to production winders, and was much simpler to work with. Later, simply for convenience, we made a benchtop version at a cost of 0.1% of what an adjacent production lookalike costs. The benchtop was also more versatile, had a greater range and was easier to work with.

Sometimes a pilot machine must be built with a greater range of operation than a production version. For example, one of my winders at Beloit was designed for 10,000 FPM when the fastest any commercial machine was running at the time was only 7,500 FPM. This winder was capable of running webs as delicate as tissue or cigarette paper, as well as webs as stout as food board such as you would find in cereal boxes. This range meant that the drive, tension control and rollers had to be designed to state-of-the art precisions. Some pilot coater machines can run multiple coating and drying methods on the same line. Machines such as these are not necessarily jack-of-all-trade compromises. If designed well, they can function in distinctly different modes with no sacrifice of quality (obviously, however, setup time and productivity will be poorer than that of their commercial cousins). Machines such as these are in many ways the most difficult of machines to design well, and may cost much more than their commercial cousins.

The most obvious alternative to pilot machines is to use one of your commercial lines to do your experiments. While this is feasible, machine time is often expensive and availability limited. Sometimes commercial machines lack the flexibility and instrumentation of a pilot machine. Also, there is the risk of rushing an experiment to keep on schedule, and seldom will you have the luxury of exploring if the run suggests a new avenue to investigate. Sometimes an off-line machine can get you the answers you need. Here, slitter/rewinders might be able to house certain experiments easily, such as investigating alternative cutting methods, and other experiments such as coating and printing, with a modest rebuild. Finally, explore the many machinery possibilities that contract converters have. Almost any converting operation can be done on a contract basis, and many will rent machine time for trials.

With any of these options for trials, the applied researcher bears a heavy responsibility to use good judgment. It is not reasonable to expect that every dollar spent on trials will result in new products and improved processes. However, most development efforts should pay back with improved profitability for the company, just as is expected of any other investment. Thus, weight should be given to simple but telling experiments as opposed to complex trials, because there is less investment to be recouped. Finally, design of experiments and good statistical practices are absolutely necessary to getting the most for your research dollar.

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