Cutting cycle times
- May 19, 2012
Software enables Select Tool to reduce cycle times on three axis work
by Jim Barnes
Times are tight in Canadian job shops, and most owners are looking for effective ways to improve productivity without excessive cost or effort.
Enhancements to machine tool programming may be one method of achieving this. What if you could improve cycle rates and quality with a simple control upgrade?
That was an opportunity acted upon by Select Tool Inc., a busy shop in Oldcastle, ON. The firm is a savvy operation when it comes to automation and CNC.
The company makes gauges, checking fixtures and other in-process jigs and fixtures for automotive production lines. It designs and manufactures everything from the simplest CMM holding fixtures to complex attribute and automated data collection fixtures. Most of the products are unique.
While productivity is an imperative for the firm, it is not the only one. Since customers use Select’s products for quality control, they have to be produced to the highest standards for accuracy.
The company describes itself as having an “aggressively proactive approach to cost management, quality assurance, on-time delivery and extensive after-sales service.” It puts emphasis on efficient manufacturing initiatives, capital investment and continual training.
Select Tool built its current facility in 1998. It includes a CMM room along with segregated machining, fabrication, and build areas. Efficiency, organization and future expansion were keys to the building’s design.
All computer-controlled equipment is networked with the firm’s engineering systems. As a result, the company can monitor and get feedback from every project it is working on. All design work is done in-house in a 3D solids environment.
As you would expect, Select has an extensive array of CNC machine tools, including five from Hurco North America—two five axis machines and three, three axis machines. The three axis machines are two VMX24s and a VMX42.
The Hurco controls gave Select Tool the option to upgrade its operations with UltiMotion, a software product.
“UltiMotion is basically a patented motion-control technology,” explains Joe Poulin, Canadian sales manager for Hurco. “It offers similar capabilities to very high end CNC controls.” The basic function of this technology is to optimize the machine’s motion, explains Poulin.
“On a normal machine, you have the X-Y-Z axis drive. The drive follows parameters that control the path the machine has to follow.” Once installed in the control, “UltiMotion manages the machine movement. You are not limited by the hard parameters that are set in the drives,” he says.
“Say you are going from hole to hole on a typical machine. Once it finishes the first hole, it is going to re-track and hop from hole to hole instead of the typical retract and move you would find on a standard motion,” says Poulin. “With UltiMotion, it looks ahead at what’s in the program and where it has to go—and it finds the shortest path to get there, using a dynamic variable look-ahead.
“If you are cutting a pocket and you’re coming to a corner, the machine normally uses the program parameters to decelerate, turn the corner and accelerate back to the feed rate,” he says. The motion control technology can optimize this process. “UltiMotion looks ahead in the program and manages how much it needs to slow down and how much it needs to speed back up.”
The savings are incremental but can be impressive. “Each individual saving might not add up to much in distance, but at the end of the program, it makes a significant difference,” says Poulin. “Overall, we are seeing machining time improving by 20 to 30 per cent.”
Programming methods do not make any difference in this application. UltiMotion works the same way. “If they use G-code, it will still do the same process,” says Poulin.
Select Tool quickly came to see the benefits of the technology on its three axis machines. “It’s on all of our three axis Hurco controls, now,” says Paul Hollister, owner. “It enables us to drastically increase our feeds and speeds on finishing… We’re getting our best feeds and speeds out of the Hurcos with UltiMotion, compared to any of our other machines.”
Select Tool has two basic types of application: prismatic machining and contouring. The contouring operations were the focus to begin with.
“We haven’t really played with it a whole lot on prismatic—drilling, tapping and hole punching. We haven’t noticed much change, but then we have not pushed the limits and the programs are rather short, typically,” explains Hollister. “We haven’t played with testing it out… but that’s next on our list.”
“UltiMotion makes the big difference on our contour machining, primarily with aluminum material,” he says. “Our contouring programs are longer and we’ve noticed anywhere from a 25 to 33 per cent reduction in machining time, and cutter life is extended.”
Hollister supports Hurco’s claims of improved surface finish. “We’re finding improvements in surface finish in the transitional areas,” he says. “If we’re running along a relatively flat or slightly contoured surface, the finish is about the same as what we were getting before, but it’s faster. However when it goes to transition—say, into a steep uprise in the corners—the surface finish looks a lot better. They seem to be able to smooth it out tremendously.”
The new technology did not require too many changes to the way the shop was operating. As far as the operators were concerned, nothing changed except that jobs were getting done faster.
Part programming changed slightly in response to UltiMotion. “It is allowing us to use higher rates of speed on our programming, because the machines can handle it,” says Hollister.
As well, some internal changes were made in the shop, modifying the logistics of transporting materials. “We actually moved some machines around that were doing one type of job before, and dedicated two Hurcos to doing a lot more finishing and contouring because of the speed difference,” says Hollister.
UltiMotion will soon be available for five axis machines, too. “We have two Hurco five axis machines—one capable of running UltiMotion, and an older machine that is not,” says Hollister. “Our next three axis machine will be another Hurco with UltiMotion, for sure.”
Hollister says that Select Tool has not tried to push the technology to its limits yet. “It does more than I expected, and I haven’t even stepped into what else it can do,” he says. “I wish I knew more about the product. Give me a few more months, and I’ll have a lot more to say about it.” SMT
Jim Barnes is a Toronto-based journalist with more than 30 years of experience in writing about manufacturing technology.