When it comes to churning out prototype models for the cosmetics and similar packaging-intensive industries, Utley's Inc. in Woodside, Queens, New York, gives the phrase "New York minute" a new dimension of meaning.
Utley's model makers, nearly 25 of the total staff of 40, routinely turn out highly detailed and precisely machined models overnight. Strictly speaking, that's not one-minute service, but in comparison to the model-making industry's usual lead times, it seems so.
What makes the Utley's story intriguing is that it relies heavily on mechanical computer-aided design / computer-aided manufacturing (CAD/CAM) techniques for work that is almost entirely like sculpture. So-called rapid-prototyping methods involving stereolithography and other additive laser sintering technologies have proven to be "not so swift" there. Paradoxically, one of mechanical duplicating's oldest tools, the pantograph mill, is still in use.
Utley's business is fast, accurate, precisely detailed and perfectly finished models and prototypes. These models are used as-is by Utley's customers for presentations to their customers, management and business partners. Utley's models are also scanned and digitized by the toolmakers who keep molding machines running for Utley's customers' customers.
Primarily, Utley's serves the fiercely competitive cosmetics industry, where even the best customers are demanding and impatient. "Our markets are cosmetics, consumer non-durable producers, industrial design, graphic design," said John Utley, vice president. "The most common products are cosmetics: compacts, lipstick cases, perfume bottles, and display cases. We can model anything you want as fast, if not faster, than anyone."
Part of the stress on speed is because Utley's has so many rush jobs, well over half. Asked why, vice president John Utley replied, "I think it is partly the nature of the industries we work with and partly because this is New York City and everybody's in a hurry here. I also think some people box themselves into corners delaying to commit to the project," he added. "Or they spend too much of their own development time getting too many estimates.
"For whatever reason, it ends up that we are the only shop with the depth to bail them out," he said. "Additionally, on many occasions, we are correcting someone else's mistakes. This happens a lot when people run with the lowest estimate, get unusable parts and then find they are a week behind. We probably get so many rush jobs because customers know they can rely on us to get the work done."
Utley's turns out 40 to 100 jobs every week, many of them on an overnight basis in most weeks, so some jobs have to be done in a matter of hours. "About half the jobs are multiple iterations or variations, the rest of them are one of a kind," John Utley noted. In many cases, the next step is starting the tooling for plastic injection and blow molding machines.
To turn out the models, Utley's relies on two very different types of CAM software:
- For importing 3D multi-surfaced CAD files, for fast rough-machining, and for detailed finishing work, PowerMILL "The software is very accurate and will not gouge," said Phil Orenstein, programmer. "This is the workhorse, it really cranks out the work."
- For decorative detailing, including "reliefs" and similar work formerly done by engravers, ArtCAM. "The software generates lifelike effects on every kind of complex, non-flat surface," said Programmer Jason Napier, "work that falls just short of full 3D representations."
Both packages are from Delcam Inc., Windsor, Ontario, Canada. The difference between them is that PowerMILL starts with 2D or 3D CAD geometry (points, lines, arcs, circles, surfaces holes, etc.) Like all leading CAM packages, PowerMILL was originally intended for cutting mating and/or identical parts that dominate the world of mechanical manufacturing. It was developed in close coordination with CAD for mechanical engineers.
ArtCAM was originally developed for jewelry manufacturers for whom fidelity to a customer's drawing or sketch artwork takes precedence over dimensional precision. As the name indicates, ArtCAM allows machinists to create lifelike physical representations such as cameos and medallions rather than mating parts. Utley's relies on it exclusively when to create or detail models from ideas laid out on paper . For details, see the sidebar, "ArtCAM Creates New Opportunities For Utley's."
"Our edge is speed of production and ability to handle complex geometry and engraving," John Utley said. "Most of the time, the design comes to us just the way the customer wants it and we do it to their spec. They know we have the expertise, so they give us free rein as to how we get it done. Using top-notch products from Delcam helps us maintain this edge."
Added Orenstein, "the CAM software, especially ArtCAM and PowerMILL, allows us to take on work, and make money on it, that not long ago we would have been turned down as too complex."
On many projects, PowerMILL is used interchangeably with other CAM packages including Mastercam from CNC Software and SDRC's legacy software, SmartCAM. However, Orenstein said, when the incoming files are big, as in many megabytes and hundreds of individual surfaces, PowerMILL gets the nod. Utley's programmers feed geometry as native files into PowerMILL from Pro/Engineer, SolidWorks, Mastercam, Vellum, Rhino, Alias, Unigraphics, CATIA, FormZ, among others.
"We have a little leeway in terms of tolerances and dimensions as opposed to doing very high-tolerance machined parts to the nearest ten-thousandth of an inch," Orenstein continued. "But speed and accuracy are crucial. Because time is so short, we cannot afford gouges. Most of the materials we cut are relatively low in cost but that's not the point. If there is a gouge or an error, there may be no time to remachine it."
Utley's works in a wide range of materials from acrylic, Ren foam and ABS to aluminum and brass. For really intricate engraving, they often prefer brass to aluminum as brass is easier and softer to work with. Moreover, since many customers' products will be finished in a gold tone, the brass tone comes close. All they have to do is polish it.
For the actual metalcutting, "if the jobs are large or have a lot of complicated surfaces," he pointed out, "you can run the machines overnight. Or you can join several programs or parts together in one long running setup." The primary machine tools for model making at Utley's are two Haas machines, a VF-OE and a VF2; two Fryer machines, a VB-40 and an MB-14; and a Prolight tabletop mill.
"In our kind of prototyping and model making," Orenstein explained, "most of the hours in a job are programming, in things like how deep to make cuts, what feed, the spindle RPM, how to define the surfaces, what toolpath strategy to use, which contours to follow and which ones to cut across." PowerMILL's "super-fast" calculation speed, he added, reduces toolpath generation time to seconds or, at the most, New York minutes.
Files for finish machining sometimes approach a RAM-gobbling 50 megabytes. Because stepovers between passes of the cutter are so small-sometimes just one- or two-thousandths of an inch-thousands of passes may be required on complex surfaces. "The finer the stepover, the finer the finish, and the less benchwork [time-consuming hand finishing] is required," Orenstein pointed out. "A really fine finishing program is big. It's processor-intensive.
"I've used most of the popular programs including Mastercam, VisiCAM, NC Polaris and SurfCAM," he said. "PowerMILL is in a different class completely in terms of its calculating speed. I've never seen anything run clean toolpaths so fast. I'm amazed. It's a programmer's dream. It's also very intuitive so it's easy to use and we've had no glitches in the program.
"PowerMILL is at its best and fastest in 3D," he continued. "If most CAM packages take a half an hour to program a job, PowerMILL will do it in five minutes." Computer speed is, of course, a big factor. Utley's programmers run PowerMILL on custom-built, dual processor PCs.*
"The development of CAM software in recent years is little short of awesome," said Orenstein. "Conventional CAM software development wisdom has been brought out of the 2-1/2D box. No longer are significant manufacturing limitations imposed on the design process that inhibit the creativity of product designers." He cited three examples:
- 3D toolpath editing capabilities. "You can delete, copy, add or move any toolpath or any selection of a toolpath and it will update instantly, this feature is extremely useful"
- Rest machining. "PowerMILL is also the best of them all. "When you're cleaning up a surface after machining with a larger-diameter cutter [remachining] or corner finishing [corner picking], it's cleaner and faster. It really does automatically remove the areas you need to clean up. I was astonished."
- High-speed machining (HSM). Every inch of programmed motion for 3D surfaces is made up of 1000's of tiny incremental movements. In the machine tool, HSM comes down to the look-ahead function, the ability of the CNC to "see" many blocks ahead in the program. For each change in direction, look-ahead gives the machine tool's drives an extra fraction of a second to slow down. They speed up again immediately after the turn, much as a car's driver slows for curves, then resumes normal speed. "PowerMILL toolpaths take advantage of this function by providing numerous HSM strategies, such as high speed loops and smooth links." Orenstein explained. "The software automatically adjusts the spindle speed and cutter in-feeds to maintain optimal metal removal rates as the machine tool's axis drives slow down and speed up again."
"We do use SLA and rapid prototyping when we feel it is the best way to make a part," John Utley observed. "But often we find it is not the best after we add up the additional finishing time and aesthetics. In general," he added, "we have found that SLA doesn't handle the level of fine detail we often work with. Even pantographs have superior precision."
There is also a lot of recalculation of tool paths. "If you need to get the machining done faster," Orenstein said, "you can always jack up the speed of a machine with more efficient toolpaths. So we recalculate and see what we can gain in time." In effect, recalculations are the what-ifs of CAM programming. At Utley's, virtually all recalculation of toolpaths is done with PowerMILL, since it gives us instantaneous readings.
One great time trap for model makers is last-minute changes. Typically clients demand them but do not extend deadlines. In this, Utley's is fortunate. Its designers and programmers usually do not have to deal with last-minute changes since so many jobs are already on a rush basis. "Often we are trying to correct someone else's mistake." John Utley noted. "Usually then the customer is in high-need mode and doesn't want to waste further time or haggle over details.
"Utley's prides itself on programmer's capabilities, especially because most of them are self-taught, they learned it because they wanted to," said John Utley. "Programming for prototyping is very demanding, especially when it's done under the very tight delivery schedules we are given.
"The time to program varies with the skill of the programmer and the features of the CAM software," he concluded. "We swear by both programmers and CAM in the shop. Our programmers are very good and the software makes it that much easier. We always find a way to satisfy the customer, but the programming speed and ease of PowerMILL is the biggest advantage here."
Editor's Note: Other aspects of Utley's operations were profiled in the article "High-Speed CAM of 3-D Sculpted Surfaces" by Phil Orenstein in Time-Compression Technologies , March/April 2002.
* Utley's PCs use Intel Corp. Pentium 4 processors with speeds up to 2.6 gigahertz per second and accessing up to 1 gigabit of RAM. All run Microsoft's Windows NT 4.0 Video cards are from ATI, Elsa add NVidia. Said John Utley: "My basic strategy for acquiring technology is to buy right after the release of the next latest and greatest' since these products have just had the greatest recent price drop and vendors have worked out most of the bugs." When we started with CAM, we relied exclusively on Intergraph machines and Wildcat video cards.
ArtCAM Creates New Opportunities For Utley's
Many jobs that come in the door at Utley's do not arrive as CAD files, IGES files or solid models. Instead they come in as graphicspictures in formats ranging from Adobe Illustrator files to paper napkins. To deal with these, they relay on software that marries engraving of lifelike reliefs with CAM; this is ArtCAM, also from Delcam Inc., Windsor, Ontario, Canada.
"ArtCAM offered a foot in the door for us with engraving work," said Jason Napier, model maker and programmer. "We started turning out really good work and customers said, Wow, you can do that?' It grew from there. ArtCAM has actually ramped this part of our business up several percentage points," he added, "which means it paid for itself in just a few months," Napier said.
While much of this work is for new types of business such as medallions, it is also very handy for adding decorative touches to cosmetics packaging which is Utley's bread and butter. These were engraving jobs that we used to turn away because it wasn't possible to do them with the older mechanical CAM packages, and machining them on a pantograph [tracer milling] would have taken so long as to be unprofitable.
"Doing this kind of work is possible with newer CAM software, but it is very slow," Napier noted. "That makes it too expensive in terms of the hourly cost of the seat license. In fact, before ArtCAM and PowerMILL (also from Delcam) it was a real scramble in programming to generate enough programs that way to keep the CNC machines going.
"One reason for that was most other CAM packages are so technically oriented," he said. "They expect you to start every job as a mechanical draftsman would. Those packages have no way to accommodate free-form work, artistry and creativity. To use them for something like this, you really have to know all the Ps and Qs and what you want to achieve before you start." Freed from ties to CAD geometry, ArtCAM starts with 2D art in any form whether it is scanned directly into or imported as a file.
Utley's also gains from ArtCAM's ability to merge different types of data into a single toolpath file. "For most of our clients," Napier explained, "we have IGES models available of their basic products such as cosmetics compacts and lipstick cases. If the customer wants us prototypes with several different logos on to or sides, we save the logo as an Adobe Illustrator file and drop it into ArtCAM to do the engraving. This gives us a hybrid metalcutting approach with the engraving done in ArtCAM and the rest of the object programmed and machined with conventional CAM packages. It's a big time saver."
"For one customer, we developed a set of medallions that came out quite well," Napier said. "They had a lizard design and the finest details, like around the eyes and mouth, required us to machine features as small as 0.0005 inch. I finalized the lizard sculpture with Adobe Illustrator, then scanned it into ArtCAM. For the finish toolpath, we used a 0.0014-inch diameter ball cutter and programmed 0.001-inch stepovers.
"On a pantograph, even with a master that was three to five times bigger than the final part, the quality just wouldn't have been there," he added. "We couldn't have done it with anything else. With these kinds of organic shapes, the other CAM packages just wouldn't be able to do it, either. All I had to do is download the Illustrator file to ArtCAM, then build up the model organically. ArtCAM has a nice way to use Illustrator to make sketches and it runs on any reasonably current PC hardware."
Another ArtCAM project literally started with cocktail napkin sketches, then went into Adobe Illustrator. Recalled Napier, "It was a series of two dozen compacts with designs that were throwbacks to the Sixtiescrazy shapes, flowers, textures of fabrics, and elaborate geometric lines. To do this with anything other than ArtCAM probably was impossible.
"We could have sculpted those, but the geometries would not have been as accurate as the customer needed," he added. "We could have improvised by taking the job into shaped Lucite and making templates. But that would have cost us double the shop hours and still would never have looked as good." Instead, Utley's machined the jobs in brass. "The models were crisp looking and we achieved a level of detail that was amazing," Napier said.
ArtCAM is a huge improvement over traditional duplicating techniques such as the pantograph mill. "Setting up a typical pantograph job usually takes all day," Napier explained, "and it needs a lot of approximation if you are engraving something on a rounded surface. With ArtCAM there is never any approximating so there is very little variance between whatever you traced and the machined part that was produced. To get the same quality on a pantograph would drive you crazy," he added. "So now they are used mostly for jobs in the backlog where we have extra time before delivery.
"ArtCAM is head over heels over everything we had before," Napier continued. "It is uniquely suited to the kind of engraving work we do and I have yet to encounter another package in its range.
It's also easy to modify and enhance, he added. "I developed some techniques that ArtCAM was not designed for such as getting into full-3D sculpting." Utley's currently uses ArtCAM Version 4.5 and is considering 5.0.
"One of our other CAM vendors also added an engraving package and asked us to try it," Napier said. "We did but compared to ArtCAM, it didn't even come close to meeting our needs. Anybody with a little programming skill can write toolpaths with it. If I didn't have ArtCAM, I would feel like I'm missing a limb."