Lasers and high-performance cutting

>Polyant had developed for NASA forward 600 feet
When is a balloon not a balloon? When it’s aand then back to cut one gore would inevitably
technical problem, a design challenge, and andistort the fabric beyond the required accuracy level.
inspiration for the development of new and moreThe obvious solution was to develop a system that
efficient cutting equipment.would move the material in only one direction.
EdgeWISE Tools founder Pat Momany —Momany is quick to credit engineer Bill Stuart with
didn’t start out at the high-tech edge of thefiguring out how to devise the software controls for
fabric cutting industry. Problems that need solving getEdgeWISE’s Single Direction Cutting (SDC)
his inventive juices flowing, and his penchant forsystem, which combines state-of-the-art laser beam
saying, "Sure, we can do that," before figuring outdelivery, material handling and motion control to
how, add up to an enterprise that’scalculate required material length and digitally
reinvented itself several times.compensate for the stretching that occurs during
Now with that trademark inventiveness and can-dohandling.
attitude, Seattle-based EdgeWISE is pushing the limitsMost cutting systems, Momany says, are driven by
of fabric cutting, in a system custom-designed to cutHewlett Packard Graphical Language (HPGL), whose
out the huge scientific balloons NASA plans to sendlimitations render it unable to handle ULDB-sized
to the very edge of Earth’s atmosphere.projects. "With HPGL, you lose accuracy over long
From boats to balloonslengths of material…you run out of math; you run
It started with boats. " I was in the printing businessout of decimal points," he elaborates. EdgeWISE
in 1985, and met a lady who was putting vinyl namesengineers have developed a new data processing
and logos on the sides of boats," Momany relates.technology that can achieve accuracy out to 16 or
"Gerber had released a 15-inch vinyl text cutter, butmore decimal places.
she was doing graphics and logos in addition to"And with HPGL, at 3,000 inches, the system would
letters. I wondered if we could somehow melt thejust stop, and you’d have to re-send the
vinyl to cut it. We started out with a soldering ironimages—but it wouldn’t have any way of
attached to an X-Y plotter." After working throughknowing where it had left off," Momany says, noting
many "thermal issues," midway through 1986that 3,000 inches, or 250 feet, is less than one-half
Momany, in partnership with another company thatthe length of a ULDB gore. "Our system can just
later went out of business, introduced a 36-inchkeep on going."
thermal cutter to the sign industry.As Momany explains the SDC’s advantages
The following year, "back when 286s were the hotfor the NASA application, he keeps bumping into his
computers," Momany reminisces, he and colleagues atcompany’s own "cutting edge" issues:
GrafikEdge helped develop Amiable Technologiesproprietary technologies, which he doesn’t
sign-cutting software, and came very close todare explain in excessive detail. EdgeWISE is currently
perfecting a swivel knife cutter of the sortpatenting the SDC system, with between 15 and 20
that’s now widely used in the cutting business.individual processes listed as claims on the application;
"I didn’t trust the software engineers," hethis is one of four patent applications the company
recalls this near-hit ruefully.has going, and Momany expects to initiate another
In the late ’80s, Momany began teachingtwo sometime this year. (The tiny company, by the
himself about lasers, and in 1990 sold GrafikEdge andway, employs three full-time and two part-time
started EdgeWISE Tools to develop, sell and serviceworkers, and uses five to seven contractors.)
cutting tools and systems. EdgeWISE debuted a rollAs it turned out, EdgeWISE’s SDC system
feed laser (RFL™) system at the International Signwas able to come darn close to the original tolerance
Association show in 1992, and received a US patentrequirement, at +/- .3 inches; but, as NASA,
in November of 1993. For a few years EdgeWISEDimension Polyant and Raven Industries continue to
licensed the technology to another company, buttinker with the composition of the balloon fabric, new
when this route failed to produce the desired growth,hurdles emerge. Simply cutting one lobe down the
EdgeWISE began designing and selling its own RFLmiddle of the run of fabric results in 40 percent
product line.waste, so EdgeWISE designed the system to cut
According to company literature, RFL technologyhalf lobes down each straight edge, to be sewn
offers significant advantages over traditional flatbedtogether afterward, cutting waste down to only 14
systems that cut with blades:the RFL takes onlypercent. This means the system must be able to
one-third to one-half the floor space of adetect the fabric edge, which was no problem with
flatbed;lasers use minimum heat, for less materialthe earlier translucent material. The most recent
distortion;lasers provide a high degree of accuracy,version of fabric, however, is transparent, so edge
consistency, control and flexibility;the extremely smalldetection becomes a bigger problem.
cut width allows for detailed work and close nestingPerformance and perforation
of components, minimizing waste;lasers decrease theMomany suggests that the SDC system would be
risk of injury, com-pared to many mechanical cuttingsuitable for a variety of applications with simple
methods.cutting patterns requiring high volume throughput,
"We started focusing on designing and developingsuch as automotive air bags. The RFL system is
other laser tools, and were invited by Eastmanfaster than a flatbed, and the SDC is faster yet, able
Worldwide, an industrial fabric company, to exhibit into handle 350 or more linear feet of material per
their booth at the 1997 Industrial Fabrics Associationminute.
show in Nashville. That’s where I met RavenIn addition to the advantage of taking up much less
Industries’ Ron Stevens, who was heading upfloor space than flatbed systems, the roll-feed SDC
the manufacturing end of NASA’s Ultra Longallows for faster throughput without increasing safety
Duration Balloon Project," relates Momany.compliance issues or the need for training. "We try to
The Single Direction Cutter (SDC) system wasmake every machine using a Class One laser
designed to provide precise beam delivery, materialbeam—as safe as your laser printer," Momany
handling and motion control, developed tonotes. By definition, Class One beams are totally
compensate for distortions due to material stretching.enclosed. If, for example, the ULDB gores were to
The Ultra Long Duration Balloon Project (ULDB),be cut with a laser moving over a flatbed, "to move
profiled in our October 1999 issue, is NASA’s600 feet, it would have to be a Class Four
latest development in near-space scientificbeam—and everyone in the room would have to be
exploration. The project aims to develop balloonlaser-trained and wearing goggles," he explains.
systems capable of supporting scientific observationsNow, EdgeWISE is working on adapting laser cutting
above 99 percent of the Earth’s atmosphere,technology to perforation applications. "We can take
for durations of approximately 100 days. Innovations60-inch-wide material and perforate it with a quarter
in materials and construction—the current design isinch separating the holes in a row, and a quarter inch
600 feet tall and pumpkin shaped, with lobes thatseparating the rows, at 85 feet per
increase its strength, and made of a one milminute—that’s a half-million holes a minute,"
five-layer Mylar-polyethylene-polyester compositeMomany says, noting that one client, an aerospace
that provides a previously unavailable combination ofcompany, uses the resulting perforated material to
gas barrier, tear resistance and strength—add up tofilter resin evenly onto parts that must be glued
a balloon that can take near-space extremes oftogether.
temperature and sun exposure, and carry a couple"The limitation on most perforation operations is
thousand pounds of equipment.mechanical; it’s like they’re using a
"Ron and I discussed those 600-foot lobes, and Irotary pincushion, and the needles break all the time,"
said, ‘Sure, we can do that,’" Momany saysMomany says. It’s not uncommon for needle
nonchalantly. "Our thinking has always beenbreakage to occur several times a week, or even
not-quite-mainstream, and that’s me.daily, resulting in four to eight hours of downtime
I’m a conceptualist; I have engineers to telleach time. "The laser perforation could be used in
me what we can’t do.manufacturing disposable diapers, band-aids, all kinds
" The enormity of the ultra long duration balloonof geotextiles."
poses huge manufacturing challenges. "The biggestWhile in Momany’s view it’s
problem was that NASA wanted the lobes to be cutEdgeWISE’s small size and flexibility that
to 600 feet plus or minus a quarter inch," Momanyenables it to take on these kinds of problem-solving
marvels. "These scientists are amazing. You get themchallenges, he also admits that the aerospace client
in a room together and they have all these ideas, butwas originally nervous about the reliability of such a
they’re some-times not very realistic abouttiny supplier. The ULDB Project provided a needed
manufacturing reality. We got them to agree to plusdose of credibility. "When you say you’re
or minus three inches; that’s a .5 percentworking with NASA, that tends to get
margin of error."people’s attention," he concludes.
Momany knew immediately that their RFL system,Reprinted with permission from Industrial Fabric
which moves material backward and forward underProducts Review April 2000. Copyright ® 2000 by
stationary cutting heads, wouldn’t do the trick;Industrial Fabrics Association International.
moving the film that Connecticut-based Dimension