Shop Solutions: Custom Cycles Roar With Powerful Engines
Owners of Harley-Davidson, Sportster, and Buell brand motorcycles, among others, and builders of custom motorcycles are always looking for that high-performance edge. Precision-manufactured engines and high-performance aftermarket components can make their bikes faster and more powerful, but, equally important today, their performance must meet emissions-compliance standards required by the EPA and the California A.R.B. (Air Resources Board).
S&S Cycle Inc.(Viola, WI) is one of the world's most respected manufacturers of high-performance engines and components for American air-cooled v-twin motorcycle engines. The company has opened an Emission Certification Laboratory in its LaCrosse, WI, facility that will allow S&S to certify engines and components to EPA and California A.R.B. standards for use by both small-volume manufacturers and home builders, and also do complete vehicle certification for OEMs.
S&S employs creative designs and manufacturing techniques, using advanced production technology to achieve the precision required of its engines and components. The company produces a large number and wide variety of high-performance motorcycle engine components in its 180,000 ft2 (16,722 m2) manufacturing plant, and employs 250 people.
Tim O'Toole, S&S Cycle's plant engineer, explains that before 2002 the plant was laid out by type of machining operation. "We did some mapping, and found how much parts were traveling back and forth," O'Toole says. "Now, one cell leader has control of an entire product's production, rather than a lathe supervisor handing off to a HMC supervisor."
To continue progress made by rearranging the plant, S&S Cycle regularly invests in new manufacturing technology, which enables the company to improve throughput and achieve higher quality. Today's shop floor features a number of high-performance machine tools from Mazak Corp. (Florence, KY).
Putting cylinder head production on a Mazak Variaxis 500-5X VMC, for example, improved cycle time by 35% compared with the former machining process using three machines; an HMC and two VMCs. The Variaxis is a vertical spindle, full five-axis machining center, equipped with Mazak 3-D Surface Integrity Software, network interface, and dynamic vibration compensation. It features a 30-hp (22-kW), 12,000-rpm, 40-taper spindle, an 80-tool magazine, a two-pallet changer system, and a 1000-psi (6.9-MPa), high-pressure coolant system. S&S acquired one of the first Variaxis machines sold in the US, now it has a total of five.
"It was huge," Randy Williams, S&S Cycle's senior project coordinator, says of the improvement with the Variaxis. "We had all of these different steps; so many operations. Now they [parts] go on, are fixtured twice and they're complete. Not only that, but our quality is just amazing," Williams adds. "We're not going from a fixture over there to a fixture over here, stacking up errors."
The newest engine entry from S&S Cycle is its X-Wedge engine, which features a design that meets 2010 emission standards, in addition to providing the performance typical of S&S power plants already in production. Again, the company turned to Mazak to provide the technology solution necessary to meet demand for the increased requirement for precision-machined components.
A two-level Mazak Palletech manufacturing cell with 52 pallet stations and two load-unload stations was selected for the X-Wedge production cell. While Palletech systems often are implemented along with new Mazak HMCs, S&S Cycle is rearranging its shop floor and using the Palletech system with four existing, stand-alone Mazak PFH 4800 HMCs, three with 120-tool magazines and one with an 80-tool magazine.
S&S Cycle expects the four-machine Palletech cell to give it greater flexibility and the capability to handle short-run projects, in addition to parts for the X-Wedge. The reason is that the Palletech manufacturing cell provides automatic loading and unloading of pallets and their workpieces that have been set up off line. Once installed, all functions, including scheduling, monitoring, program uploading and management, and operation results, are available from the cell controller over networked PCs and browser-based software.
The first production targets for the Palletech cell include oil pumps, tappet blocks, and gear covers. Eventually, the company will add other, shorter-run products to the Palletech cell to take advantage of its flexibility and variety of tools available.
"Our goal is to run them all the time," Williams says. "The goal right now is two staggered shifts. That gives us three and a half hours between shifts to go untended. Two shifts can do the work of three. The machine time won't be any different, but we're looking at improvements in the labor that it takes to produce the parts, taking control of the whole area, the inventory, material moving, everything," Williams says. "We could see as much as a 50% reduction in operating costs. We're also going to do more in-process inspection within the Palletech cell."
The accuracy of the PFH 5800 HMC is allowing S&S to "window machine" both elements of a two-part product, such as crankcases and oil pumps, at the same time, effectively halving the time it takes to produce the component.
By window-machining the two sides of a crankcase on the PFH 5800 HMC, S&S is able to take what was an 82-min operation and do it in 42 min, and also eliminate an additional six-min lathe operation.
"What allows us to go to this concept is machine accuracy," says Williams. "We've changed the way we fixture things because of the reliability and performance of the machines."
In another part of the plant, a Mazak PFH 4800 HMC window-machines four complete oil pumps at the same time. "Ten years ago, no one would have thought we could do this," Williams says. "We're really proud of what we've been able to do."
Until recently S&S had purchased its camshafts from an outside source. That was before the company purchased a Mazak Multiplex 6200Y with an integral GL-100 gantry robot loader. The Multiplex takes a piece of bar stock and does the majority of the camshaft turning and secondary machining in one operation.
"The Multiplex with a gantry also gives us new capabilities: done in one setup, on-machine probe inspection, better product flow and material handling, and a high degree of automation and untended machining," Williams says.
Once finished, replacement parts are packed and delivered to dealers for sale. Finished parts for complete engines are sent to the final assembly area where the engines are put together by hand, creating an interesting confluence of high-technology automation and the human touch at S&S Cycle.
Downhole Drilling Requires Tough Measuring Solution
As a supplier of precision-machined drilling products to the global oil and gas industry, Halliburton (Houston) can manufacture drills that are truly bigger than life. In the movie Armageddon, viewers see a drilling team obliterate a fictitious asteroid by using a real drill bit which is part of a life-sized gigantic drilling machine.
To help create this authentic machine, Halliburton, which excels in bit optimization science used for drilling hard rock and hard-to-drill formations, provided a large 28" (711-mm) diam drill bit for the machine.
Of course, the typical application for Halliburton's drill bits is oil recovery (not motion pictures!). Today, recovering oil is more critical than ever. Worldwide energy resources are being stretched tight with the demand for oil and other energy sources greater than ever and expected to climb.
At Halliburton's 270,000 ft2 (25,084 m2), 450-employee facility in Conroe, TX, employees produce drill bits, ranging in size from 2 3/8.30" (60.3.762 mm), which must be manufactured under stringent guidelines to provide maximum performance. Standards include meeting tolerances of plus/minus thousandths of an inch in some applications and plus/minus tenthousandths of an inch in others.
Tight tolerances aren't the only gaging challenge Halliburton's calibration technicians face. They must often measure parts in harsh, wet, and difficult conditions, and they are always conscious of the need to keep costs down.
"Frequently, we have to check parts with coolant dripping on the gages," says Alex Morris, senior gage calibration technician. "We use a variety of gage types and brands in our shop. We were routinely confronting situations where our calipers and micrometers were simply not performing well. The tools were not holding the tolerances we require, and the coolants were often gumming up the tools so that we could not use them to measure parts. We were constantly replacing micrometers and calipers, typically eight or nine per month," Morris says.
Halliburton contacted The L.S. Starrett Company (Athol, MA) to help solve their dilemma. Starrett offers an extensive range of precision measuring hand tools, which are well known for their accuracy, reliability, and quality.
To begin, Halliburton examined Starrett electronic calipers. One of the tests that Halliburton used to determine their effectiveness was to literally drop the gages in coolant. Morris says the calipers stood up just fine, even after being submerged.
The Starrett team was able to demonstrate an effective solution to Halliburton. Starrett No. 797 series electronic calipers proved to be the right choice because the tools offer IP65 level protection, which is well-suited for harsh manufacturing environments. The calipers maintain their accuracy while resisting coolant and shop contaminants including water, dust, dirt, and metal chips. According to IEC 529, the international standard for degrees of protection provided by equipment enclosures, IP65 stands for a "6" protection against ingress of dust and particles and a "5" protection against water jets projected by a nozzle from any direction for a duration of three min.
"When the old calipers were replaced with the Starrett 797 calipers, the operators could not believe how much better they performed. They exclaimed at how easy the Starrett calipers were to use, and how they were able to successfully check parts with coolant dripping on the gage," Morris says. An LCD with a character height of 0.310" (7.87 mm) makes the 797 easy to read.
Halliburton was also in need of micrometers for drill bit applications 1" (25.4 mm) and under that could maintain accuracy under harsh, wet conditions. Starrett was able to offer a suitable solution for these difficult manufacturing conditions.
Halliburton chose the Starrett No. 795 series electronic micrometers, which provide an IP67 level of protection against coolant, water, chips, dirt, dust, and other contaminants in hostile shop environments. According to IEC 529, the "7" in the IP67 rating provides protection against the effects of immersion in water under stated conditions of pressure and time. Additionally, the 795 micrometers offer a 0.275" (7-mm) high-contrast LCD digital readout and push-button features providing zero at any position, the ability to retain / return to the true zero reading of the micrometer, and inch/millimeter conversion.
For a suitable micrometer solution for applications over 1" (25.4 mm), Halliburton looked at performance factors. Calibration technicians use the micrometers during the finish stage, typically while the part is on a four-axis CNC lathe. The part cannot be removed from the machine for gaging purposes so measuring drills can be awkward. Holding tolerances during this process are critical and the older micrometers were not proving effective.
Halliburton determined the Starrett 733 electronic micrometer line could provide them with the range of functionality they required. The 733 line offers full-function electronic outside micrometers with the ability to output measurements to a variety of peripherals. A high-contrast LCD digital readout reduces errors. Accuracy is ensured by a stable one-piece spindle.
"When the old micrometers were replaced, I received a lot of the same type of feedback from the operators as for the Starrett caliper," says Morris. "They said the new micrometers held their tolerances better, would consistently repeat, and were easier to read."
In all, the Starrett tools have improved our gage R&R [repeatability and reproducibility] by 50%," Morris concludes.
Making Better Engineers with CAM
Since 2003, the engineering program at Robert Morris University (RMU; Pittsburgh) has placed all of its graduates directly into engineering roles with manufacturing companies or into advanced degree programs in top-quality institutions.
Manufacturers have included companies such as US Steel, Curtiss-Wright, Raytheon, Honeywell, Fed-Ex, and Schoeder Industries. Engineering programs have included Case Western Reserve University, Carnegie Mellon University, the University of Pittsburgh, and Penn State University.
One of the secrets of this success is RMU's philosophy of tightly integrating the theoretical and computational aspects of engineering education with practical real-world applications. RMU offers ABET-accredited programs in mechanical, software, and industrial engineering, as well as manufacturing engineering. In fact, RMU is home to Pennsylvania's and the mid-Atlantic region's only ABETaccredited Manufacturing Engineering degree. ABET accredits some 2700 engineering and technology programs at more than 550 colleges and universities nationwide.
Engineering at Robert Morris is characterized by small class sizes, personalized attention, dedicated faculty, and excellent laboratory facilities in the Learning Factory that are used in every undergraduate engineering course. Students head to the Learning Factory where they use industrial-grade software and equipment to conduct research or solve problems that reflect their classroom work.
During their senior year, students become involved in a capstone design experience called "Integrated Engineering Design." Many will manufacture their designs in the Learning Factory using a Haas Automation HMC or VMC. Students generate all of the toolpaths for these systems using Mastercam X software from CNC Software Inc. (Tolland, CT), which they master long before their senior year.
Senior faculty members at the RMU School of Engineering, Mathematics and Science shared their views of how CAM software is being used as a bridge to integrate the theoretical with practical aspects of design engineering and manufacturing.
"Students use the Mastercam X program selectively for a variety of class projects that call for something to be machined. It's the principal way that CNC code is generated at this university," explains Winston Erevelles, Dean of RMU's School of Engineering, Mathematics and Science. "It has been our CAM software of choice since the inception of our program in 1999."
"What I like about this CAM program is that it offers versatile surface modeling capabilities, and I do ask students to use these capabilities very early in their RMU education," says Arif Sirinterlikci, director of the engineering laboratories. "I used it to walk through a set of exercises dealing with different surface types. I think this is very important because engineering students tend to lack surface modeling experience, so I have embedded a good number of examples in the course they can actually use."
Mastercam X is often used to generate files for rapid prototyping of parts that are made either by conventional machining or stereolithography. "Mastercam X has many uses, whether it is modeling, generating code, visualization, or generating robust STL files. You also have a post processor that is very open to customization. This allows people like us, who run an integrated learning factory with an automated machining and assembly cell, to customize the post processor to interface with our robots and PLCs."
"It's an easy software package to learn, to get up and running on, and frankly I've seen middle school and high school kids [through RMU's outreach programs] machine parts within a very short time. For one of these students to knock out a part within two or three hours is pretty remarkable," says Erevelles.
"We provide students with code generated in Mastercam X and we ask them to concentrate on interpreting, rather than writing the code. Up to that point they have written G and M code, but haven't read any code written by somebody else," says Sirinterlikci. "Assignments like this help improve the students' ability to work with the CAM software at a deeper level."
"Philosophically, RMU is about problem-solving. Software is not a substitute for thinking but a valuable tool to augment thinking, to expand thinking. Without the tool, we can work on a simple problem only. With the tool, we can work on a more challenging problem or on different facets of the same problem," says Joe Iannelli, Engineering Department head.
"When we manually wrote G and M codes we had the geometry and the toolpath which we had to model. But this didn't allow us to try multiple what-if scenarios," Sirinterlikci says. "Mastercam X is more than a tool that takes away the drudgery of generating multiple toolpaths. It has an open architecture, so we don't have to follow a set procedure. In this sense, it's more like a scratch pad. It allows us to experiment, but the sequence can be worked out later."
Sirinterlikci explains: "This program allows us to explore questions like: In how many different ways can this machine work? What tool combinations can I use? Can I change my speeds and feeds on the fly to make a better product or a lower-cost product? Can we apply more intelligence to the process? A student can evaluate a variety of alternate competing scenarios, and then pick the one that optimally solves the problem that she or he is investigating."
He is careful to explain that the software is not a crutch: "We are not teaching software. We are teaching the intelligent use of software. It allows students to become more powerful, turning their ideas into reality. Mastercam X allows students to become better engineers."
Multitasking Is Big For Small Shop
A small contract manufacturer requiring faster cycle times to meet customer demand has taken a technology leap with the purchase of its first multitasking machine.
Apex Engineering and Machine (Logan, UT) opened its doors in 2003 to make parts for the aerospace and medical markets, and the aftermarket for ATVs and snowmobiles, as well as performance parts for roller coaster/thrill rides in the amusement park industry.
Conventional machining wasn't cutting it—literally—as fast and efficiently as customer needs and company growth required. With their runs at 1.10,000 pieces, the goal was to migrate toward 20,000-plus part runs. Adding a multitasking machine to increase production and efficiency not only raised their performance level, but opened doors to new business.
Having worked for other shops, Apex co-owners Travis Zollinger, president, and Brian Black, VP, decided they could do a better job and make more money by running a shop themselves. Prior to purchasing their fourth machine from Okuma America Corp. (Charlotte, NC), a Multus B-300 multitasking machine, the shop had four VMCs, including two four-axis machines, a lathe, one EDM, and an HE&M automated saw.
Even before receiving their first Multus, a new opportunity was quoted, turning their goals into reality.
"When we bid on the stainless cable ends for the first time, I think we were bidding against 30 or more other shops," says Zollinger. "Knowing what machine tool we would be using, the customer liked the way the parts were going to be built, and knew that the quality would be good."
Zollinger had his concerns before purchasing their first multitasking machine. "We took a flying leap, and we were scared to death of it at first," he says. "I fretted about spending that much money, but there were the opportunities with the machine—and the value overall. However, everything that we have done to increase the capability in our shop through investment in technology has paid off."
After Apex Engineering received the Multus, Black says that their customers would design parts around the capabilities of the machine, making it an easier process for everyone. "Your whole vision of how parts can be made changes after you see how the Multus works and understand what it can do," he says. "We want to be ahead of our competitors. We soon found we needed another machine. One wasn't enough. To be competitive in today's market, you've got to take the leap."
Apex led their competitors and ultimately won the bid to produce a family of products—a stainless cable crimp end for a popular thrill ride. It's used on machines that shoot people up and down vertically at various theme parks. The rides are driven by air and use several 5/8–3/4" (16–19-mm) cables. A large piece of stainless covers this cable, and a hydraulic press is used to crimp the cable around it so it forms, for all practical purposes, a single, seamless piece.
The cable crimp end begins as 303 or 304 stainless bar stock from 1.5–5" (38–127 mm) in diam and 5–13" (127–330 mm) in length. The process begins with a turning operation, rough turn, and finish turn, followed by a drilling operation. Tooling used includes Kennametal 5510 grade inserts for OD turning, Sandvik Coromant cutters and holders, and Iscar CamDrills.
Before the Multus was purchased, the process required drilling followed by finish-boring an ID hole to get the required surface finish. Now, with the Multus, the same hole is produced with one drill with a superior surface finish, to callout specs, and achieves tolerances varying from ±0.0025–0.0035" (0.064–0.089 mm). Next, the subspindle accepts the part to continue a rough-turn and finish-turn on the spherical ball shape, then proceeds to a plunge-milling operation to remove the majority of excess material with a 2" (50.8-mm) diam Sandvik 210 cutter.
"This is a really impressive process to see on a multitasking machine, because it displays the capabilities of the torque and horsepower of the Okuma Prex motor," explains Zollinger. "During the cut, it goes to a full 2" radial engagement with a ¼" [6.35-mm] stepover depth of cut, and a feed rate of 18 ipm [0.46 m/min] at 500 fpm." Continuing with the final milling process, a hole is drilled and milled using a mill bore to 0.0001"/-0 tolerance. The Multus completes the process by engraving the part and batch number on the finished product.
"One of the nice things about having the Multus is that you don't have to worry about orientation. It's programmed so that all of your parts are clocked exactly right, as long as you program it correctly," explains Black. "And when it comes to vibration dampening, some of the parts produced suspend quite a way from the spindle; however, we don't have any problems with chatter."
One initial issue to overcome was the technology itself. Zollinger explains: "The Multus is just more of a challenging machine, and running it requires someone with a higher skillset than is needed to run a conventional machine," he says. "But once the programming is done, you're able to save and store the program on the control and reuse the program again. You spend a little more time up front on the programming, but depending on how much hardware or tooling there is on the machine, you've cut out all of the set-up time, cost of fixtures, etc. We can now fly through setups."
The Multus B-300 features the THINC–OSP control, a PC-based control with open architecture that boasts a 40-GB hard drive and readily accepts most third-party Windows-based software. Apex uses MasterCam X2. Included in the posting of G-code through MasterCam X2 to the control, Apex utilizes slope machining to program at a slope or angle. The slope machining function essentially rotates the axis coordinate to the desired angle so that program commands requiring two axes of movement can be made with a single-axis command. In addition to this, slope machining also provides the operator with the ability to interrupt the automatic cycle and move the tool in two-axis motion with the pulse handle and single-axis control. This can also be achieved in manual mode. Simply put, slope machining simplifies complex programming.
For this particular part family, each complete part takes 16–30 min to run. With six operators on the floor running seven machines in two shifts, the cycle times for this particular part run allow an operator to load a part and have time to service other machines—sometimes running four machines at one time.
"Because we can now make parts in one operation, instead of using multiple machines and/or setups, we are very happy with the results," says Zollinger. "The parts are better now, and the Multus B-300 eliminates a lot of labor, and human error, and increases the output quality."
This article was first published in the June 2008 edition of Manufacturing Engineering magazine.