Shop Solutions: Antenna Maker Tunes in to CAM
Shop Solutions is edited by Senior Editor Jim Lorincz
R. A. Miller Industries (RAMI; Grand Haven, MI) began making antennas for the military in 1956, eventually expanding antenna production to the automotive industry (for long-haul trucks), as well as to the general aviation and marine markets. Approximately 75% of RAMI’s production is military, 23% automotive, and 2% general aviation. The company develops antennas from the ground up, doing all the engineering, parts machining, cleaning, plating, painting, and assembly for all but the automotive line, which purchases parts because those parts require several six-spindle multitask machines, for which it has no space.
RAMI’s machine shop manufactures its parts from aluminum, brass, copper, Delrin, Teflon, and occasionally, stainless. While short runs of 25–150 pieces are typical for general aviation, military production often requires tens of thousands of parts a month. Retirement of manual machines in favor of CNC machines continued. In 1995, when machine shop lead programmer, Matt Smith, started working at RAMI, he began on manual screw machines, moving to automatics within a month.
Smith’s introduction to CNCs came in 2000, with a Miyano BNC-42. "Because I came from hand screws, and because every job we moved from hand screws had to be programmed, I learned manual programming quickly," says Smith. "At the time, we were only doing standard two-axis lathe work, nothing complex."
The shop slowly added CNCs, all programmed by Smith and veteran programmer, Thau Nguyen. In 2006, the shop acquired its first multitasking CNC, an Okuma LT, for a dedicated job. "Until then, all my programming was for two-axis lathes and three-axis mills, so using M functions, live tools, and Y-axis together was a bit overwhelming," says Smith, "but we got that job running and didn’t have to touch the program for two years."
A second Okuma LT allowed Smith to become more acquainted with multitask programming. It would take a week to program a part, but it paid off for high-volume parts. Soon, RAMI was achieving a business volume that exceeded capacity. Specifically, two parts for a military antenna required multiple turning and milling operations on multiple machines. Making the parts was a lengthy, labor-intensive process, which couldn’t continue without sacrificing production of other parts, so they contracted out for the two parts.
When deliveries were taking longer than desirable, acquisition of a machine that could do all the operations in one setup was seen as the solution, but again the company didn’t have available floor space. RAMI’s continuing growth had filled its 70,000 ft² (6503-m²) facility. To create capacity, RAMI acquired and renovated a 9500 ft² (883-m²) building across the street, expanded it with a 35,000 ft² (3252-m²) addition, and moved the self-sufficient automotive line there, freeing space for shop expansion.
In 2010, RAMI purchased an Okuma MacTurn 250 multiaxis, multitask machine with milling head, bar feeder and Royal Rota-Rack parts accumulator, specifically for the military contract of 3000 complex units a month. Smith and programmer-machinist Rich Stenberg, hired for his Fanuc and Okuma OSP manual programming expertise, quickly determined that the MacTurn would not be programmed manually, that CAD models would be needed, and that a CAM system was necessary.
"The savings paid for the machine
and software in under a year, with
the added benefits of full control
and parts when we need them."
In June, RAMI acquired Autodesk Inventor for CAD, and in August, the shop installed two seats of GibbsCAM (with MTM and five-axis modules) on a network. GibbsCAM was the first programming system for both programmers. "GibbsCAM was easy to learn, and really easy to use," Stenberg says. "I don’t have to trig out anything. Engineering provides a solid model IPT file from Autodesk Inventor, which opens in GibbsCAM. I turn on the Profiler to show cross sections, pick points to tell the software the path I want, and it just does it. It saves a lot of time."
The experience was similar for Smith. Even as a fast on-machine programmer, a frequent challenge he faced was blending between an angle and a radius on a lathe. "That’s difficult at the machine, if you don’t have key points on the print," he says. "With GibbsCAM, I turn on the Profiler, and I have everything I need. For me, that was the greatest immediate benefit. No more trial and error to find the blend, and no repeated trips to engineering to get geometric points. It knows exactly where the angle stops to meet the radius, generates a perfect blend, and I don’t have to change a thing in the program. It saves hours."
Sue Boelkins, the RAMI mechanical engineer creates the CAD part models using Autodesk and its Autodesk Mechanical Desktop subset from other engineers’ concept sketches or ideas, but only creates 3-D part models when they are ready to machine parts. She only gets an occasional change request from Smith, but never for faulty models. "Matt will ask if we can change a radius to accommodate a cutting tool, or add mounting holes to fixture a part for a secondary operation. Otherwise, they just open the Inventor IPT files in GibbsCAM and program directly from the models, without a problem. It works very well."
The MacTurn was Stenberg’s first experience with dual spindles, dual turrets and five-axis machining. Previously, the shop would have the machine-tool supplier synchronize turrets and spindles and optimize the program. "Now," he says, "with GibbsCAM’s Sync Manager, it would have to be an extremely complex job for us to ask for help. GibbsCAM does what we need, and I don’t know how we would program multiple axes, oscillating head, and lower turret without it."
Sync Manager inserts sync codes at proper locations to synchronize tool groups (turrets), and flags conflicting motion, such as attempting to do cross drilling while doing a turning operation, or tools and turrets moving toward collisions with workholding devices or each other.
Another GibbsCAM feature Stenberg uses as a precaution with every program is Cut Part Rendering. "It lets me dry run the program, to prevent problems at the machine," he says. "It tells you if there’s something wrong, even when you use it only for graphic toolpath verification. But if you turn on the crash alerts, and it finds a problem, it won’t let you proceed until you clear the problem. Even with alerts off, it shows if a toolholder is bottoming out or a tool is making a rapid move into the workpiece, showing the path in red. You can run through individual operations as you program, run the whole program, correcting as you go, or inspect all of it before fixing any problems."
Upon learning both the MacTurn and GibbsCAM, the shop went into high-volume production with the parts. Because the parts all use the same bar stock, switchover between parts is achieved by simply loading the next program.
In the year since acquiring GibbsCAM, the shop reprogrammed several parts for the MacTurn, significantly reducing production time. Moving to a single machine also reduced setup and part handling, freeing 75% of the required labor to make more parts on other machines. Parts that required 25 min of machining time with two lathe and three mill operations, now take 6 min from bar stock to completion. "We’ve made that huge improvement with several parts," says Smith. "The savings paid for the machine and software in under a year, with the added benefits of full control and parts when we need them."
The MacTurn MTM now runs untended for 10–12-hr periods, as the company fulfills a monthly military contract requiring 3000 units a month, each requiring five different parts from the MacTurn. Having GibbsCAM enables the programmers to reduce programming time for the other 15 CNC lathes and mills as well.
R.A. Miller Industries now machines all of its parts for military, general aviation, and marine antennas. "If all continues to go well, we may need to get another MacTurn," says Smith. "For now we just need to tie the MacTurn into the network to send programs directly, because now it requires a thumb drive and a 3' walk from one of the GibbsCAM stations." ME
For more information on Gibbs and Associates, go to www.gibbscam.com, or telephone: 805-523-0004.
at Aerospace Shop
Prigel Machine (Hood River, OR) celebrated its 10th anniversary in 2012. In December 2002, after many years of working as a lead technical specialist supporting injection molding for wind-surfing products, Brian Prigel pursued his dream of owning a small machine shop. These were difficult economic times, but there was one advantage: shops that were going out of business were auctioning off excellent used equipment. Prigel bought some and began networking for customers.
"I have never encountered a situation where I couldn’t get Mastercam to make
the tool do exactly what
I wanted it to do."
Like many small machine shops, Prigel traveled the path taken by many—beginning with manual equipment, growing, and then adding CNC equipment and advanced Mastercam software from CNC Software Inc. (Tolland, CT) to do the CNC programming. At the outset, Luck was on Prigel’s side. A nearby start-up company that was producing unmanned aviation system drones needed a person with Prigel’s skill set. Over the next few years, this customer was joined by others. These customers needed parts for the cameras and avionics used by drones, for ground support equipment—such things as catapults and "skyhooks"—and matched compression molds for making carbon-fiber composites. Prigel Machine had officially launched itself into a fertile niche.
Prigel and his staff programmed CNC equipment manually at first, and then with inexpensive CAM software with limited features. "In 2006, I hired a production manager, and he convinced me that I needed to purchase Mastercam to keep pace with the volume and growing complexity of the parts customers were sending us. I did it and we haven’t looked back," says Prigel.
The company now has 11 CNC machines that are programmed with four seats of Mastercam, one multiaxis, two mill level 3, and one lathe. Prigel himself is one of the three programmers. Having limited CAD/CAM experience, he admits that he struggled with the software at first. However, a tenacious self-learner, he soon discovered where everything was in the program. Now he can’t see how his company could possibly get along without it.
The many benefits that Mastercam offers the shop for CNC programming include precise tool control, high-speed 3-D toolpaths, and power programming.
Without total control of tool movements with Mastercam’s precise tool control, it would be difficult, if not impossible, to fulfill the design intent for many of the unique parts Prigel Machine’s customers send their way. Prigel believes that anything his customers can design on their CAD systems, he can program for machining on his CAM system.
"A lot of people that come directly out of school or don't have the machining background do what I call black box programming where they just take the defaults and whatever comes out is what they get," says Prigel. "I approach it differently. Having come from manual machining to CNC, I always know what I want the tool to do. I have never encountered a situation where I couldn’t get Mastercam to make the tool do exactly what I wanted it to."
Prigel Machine has maintenance licenses for Mastercam, which entitles the company to free upgrades and unlimited support. So Mastercam users at Prigel are always learning about new ways to use the program to accomplish manufacturing objectives more efficiently. Recently, the company has been taking advantage of an array of 3-D high-speed toolpaths that provide more tool engagement with a shallower depth-of-cut to improve machine cycles and reduce tool wear. They allow the company to machine very complex parts with as few as four operations.
As an example, Prigel cites a thin-walled camera bracket his company manufactures. It calls for a significant amount of pocketing to remove about 99% of the weight from the workpiece. He estimates that those complex operations would have taken twice as long using conventional toolpaths. He also says that these types of cycle reductions are now being applied to about a quarter of the machining operations in his shop for substantial savings.
Of course, cycle time reductions of this magnitude could be obtained in CAM programs generated by other types of software. But they would involve laboriously going back through the program and manually adjusting settings at many locations throughout the program. Prigel's cycle reductions were obtained immediately after initial programming with no subsequent adjustments.
About one-quarter to a third of the jobs flowing through the shop are prototypes. These parts frequently require complex programming and result in short runs. So there is little margin for error before the profit margin on a job can be lost completely. In spite of the difficulties that prototyping presents, Prigel is committed to doing this work, because it cements relationships with the customer and leads to more profitable production work.
Using the CAD system's powerful interface that puts frequently used tools at the operator's fingertips and automated toolpaths that reduce the need for numerous operations, reduces programming work that used to take days down to hours. Once a program is completed, Mastercam's computer simulation features, Backplot and Verify, are used to automatically determine that the program will run on the machine tool without crashing and that it will indeed remove a sufficient amount of material to meet specifications.
Prigel Machine is positioned in markets with upward trajectories, and the future looks solid as long as it can acquire or evolve the talented human power resources it needs to keep its CNC equipment operating efficiently. Steady growth has required that more of Prigel’s and his production manager’s time are devoted to activities other than programming parts. This means that the company is currently short at least one programmer and will be looking for even more in the months ahead. If the prototyping volumes keep up, Prigel estimates that one seat of Mastercam will be required to support three CNC machines. That means more of his machinists, ideally all of them, will need to be skilled programmers.
The company is exploring a number of avenues for obtaining or growing people with these skills. They include using the services of its reseller, MCAM Northwest (Oregon City, OR), to do more training; hooking up its own machinists with self-paced learning programs such as Streaming Teacher; and working with his local Technology Alliance to encourage local educational institutions to devote more of their resources to manufacturing education.
Since 2003, Prigel Machine’s sales have been progressively higher every year except one. Now the company plans to break ground for a new facility to accommodate this growth in the spring of 2012. ME
For more information on Mastercam/CNC Software Inc., go to www.mastercam.com, or telephone: 860-875-5006.
Vending Sharpens Tool Management
Pentagon EMS Corp. (Beaverton, OR) is a global leader in the PC board assembly tooling market. Founded in 2002, the electronics manufacturing solutions company grew ten-fold in its first three years of operation. Today, Pentagon has more than 50 employees, a satellite manufacturing facility in Mexico, advanced CNC machining technology, and, more importantly, countless strong customer and supplier partnerships to enable it to offer unmatched product and service excellence.
According to Hugh Young, production manager for Pentagon EMS, the company prides itself on designing and manufacturing tooling that makes PC board assembly operations fast, accurate, and reliable. "Our line of work revolves around quick turnaround times. When a customer approves their tool design by noon, we make it, assemble it and ship it overnight, enabling them to use it the very next day."
Because everything at Pentagon EMS moves so rapidly, Young says he can’t afford to run out of the tools that keep the company thriving. "It’s never an option for me to tell a customer we can’t do their job today because we’re out of an end mill," he notes.
Young knew it was time to replace his inventory management processes when a regular cabinet with sliding drawers just wasn’t cutting it anymore. "I never knew if a machinist broke five end mills the night before, leaving us completely out of them."
With inventory control being at the top of Young’s mind, he chose a vending solution from MSC Industrial Supply Co. (Melville, NY). The system incorporated an automated dispensing unit with "add-on" frame that enhances the tooling stock process, bringing inventory management to the next level at Pentagon EMS.
"When researching vending equipment, I found several companies wanted to sell me candy-type vending machines. However, I liked the sophistication of the MSC solution, and, as a current MSC customer, I knew the pricing was going to be right where it needed to be," says Young.
MSC’s vending system electronically integrates with Pentagon EMS’s business network, a benefit that allows Young to enjoy worry-free inventory management, because he has complete control over reordering, audit trails, and reporting capabilities. "It’s great. I can look every morning to see how much of each tool I have. Plus, I have my minimum and maximum set to where I never run out of anything," says Young.
Breakthrough productivity improvements using MSC’s vending system have lowered Pentagon EMS’s overall tooling spend. The MSC dispensing unit also provides 24/7 secure access, emergency override during power outages, cost-saving documentation, and automated replenishment. Plus, as Pentagon’s needs change, MSC’s vending solutions have a modular design for easy reconfiguration.
Young says that when he originally started talking about purchasing a tool crib for the company, several employees thought it would be the end of the world. Many assumed they would be spending all day trying to get the tooling out of the machine. However, they quickly discovered the easy-to-use touch screen takes approximately 30 sec to log in and get their tool.
As it turns out, Pentagon EMS is anticipating more growth in the near future, and MSC will play a strong role in helping the company continue to run this successful business more efficiently. Currently, Pentagon EMS is in the process of getting ISO-certified and increasingly taking on new job-shop work.
For more information on MSC Industrial Supply, go to www.mscdirect.com or telephone 516-812-1608. ME
This article was first published in the March 2012 edition of Manufacturing Engineering magazine. Click here for PDF.
Published Date : 3/1/2012