Shop Solutions: CAM Software Speeds Formula One Racers
If a precision chassis part isn’t made correctly for a Formula One race car, the vehicle could be “stuffed right into a wall,” says Phil Kightley, co-founder and managing director of Taylor-Kightley Engineering (Northampton, England, UK).
Kightley should know. On a daily basis, his company manufactures precision parts to the critical tolerances demanded for Formula One race cars. When a car is racing at speeds approaching 200 mph (321 km/hr) or faster, an incorrectly machined chassis part can cause improper airflow and send the car airborne.
Before becoming involved with component production for the motorsports industry, Taylor-Kightley did general machining, both lathe and mill work. “Originally, most of our parts could be produced using a three-axis milling machine or two-axis lathe,” says Kightley. “We didn’t need a CAD/CAM system for those parts.
“We live in an area where there is a lot of auto-racing parts work. It just crept in while much of the other work died out. When we moved into the motorsports industry for our complex parts, which we’ve been doing for ten years now, we bought Mastercam Version 4,” Kightley explains.
Taylor-Kightley expanded its machining capabilities and adopted new technologies in its 14,000 ft2 (1300 m2) facility to manufacture components that are mostly one-off prototypes in materials such as titanium. As a result, the 34-employee company has retained its leadership as a supplier of precision parts to the motorsports industry, as well as serving other fields such as the defense industry.
Included in Taylor-Kightley’s array of cutting-edge technology is the latest Mastercam software from CNC Software Inc. (Tolland, CT). Using Mill Level 3, Lathe, Solids, and CATIA interface, the company is able “to take on the most complex components and then machine them straight away,” says Kightley.
”Motorsports is where the company’s most demanding work comes from, but it isn’t limited to Formula One race cars. The company also does work for CART series cars, Toyota Racing, and Cosworth Engines. “Consequently, we’ve done all types of motorsports parts from engines to chassis,” adds Kightley.
In the past, most of the company’s work was for engine parts. Within the last three years, it has changed to include chassis components. For engines, the company manufactured auxiliary parts like gears, pumps, fuel-injection rails, spacers, liners, rotors, gear-box internal parts, fine splines, and piston rings.
“We never did major parts like heads or blocks, because most motorsports teams make their own engines and major components,” he explains.
“The beauty of dealing with Formula One racing companies is that every incremental improvement to a precision part will provide an enormous competitive advantage when the car takes to the track,” says Kightley.
For example, chassis stabilizing blades are designed to meet strategic airflow objectives. The part may look simple, but the shape must be machined to 8 µm.
Kightley says that chassis components involve very complex five-axis milling, with programming time reaching 200 hr or more for one prototype part. “A typical batch of motorsports chassis parts look like they should have been cast,” remarks Kightley, “but they are all made from billets using five-axis machining to save time.
”Taylor-Kightley has found that Mastercam’s new surface project toolpath with 3-D blend is well-suited for achieving shapes with blended surfaces, which offer racing product suppliers significant air-flow improvements. This helps the shop get the job done quickly and accurately in one pass, saving the time and extra cost associated with the toolpath changeover of older programs.
One job that Taylor-Kightley is machining for Toyota is a prototype hydraulic accumulator using 105 cutting tools. It’s only 8" long × 6" square (203 × 152 mm). It isn’t a massive part, but it’s complex, with a number of cross-drilled and linked holes. It was very difficult to manufacture, needing 3-D machining over every surface, and it had to be produced on a five-axis machine. It also required deep-hole drilling to link up holes.
“Mastercam helped because it’s very easy to use and to select different views,” Kightley says. “It’s very logical when it comes to setting all your graphic views, and helps us see how we’re going to approach each compound angled hole. You could never do this without a CAD/CAM system. It would just be impossible. It is also an excellent surface modeler that helps when building on extra workholding and masking,” he explains.
For engine-related parts, Taylor-Kightley never sees the easy jobs. Many of the five-axis jobs require machining undercut areas with solid-carbide ball end mills, which means it’s essential for the tool shank to be contained to avoid collision.
With Mastercam Version 9, the shop saves time with its most commonly used toolpath: flowline five-axis cutting with the tool shank contained along a straight-line chain. Before Version 9, users had to post the NCI file of a five-axis flowline, and then use the Focus five-axis C-Hook to convert the NCI to one that contained the tool shank through focus points. Now programming time is saved because this multi-stage process is self-contained in a single operation that can be easily changed and regenerated.
Kightley points out that another “nice feature of Mastercam is that we can put a profile on a tool shank, and basically use a fixed point on it instead of having a single focus point. We can actually focus the tool down a line, shape, or profile. This allows us to get the most optimum position, and change that position with the tool shank as it travels down the profile, which is really quite useful.
”The company also uses Mastercam to simulate machining. This gives them an idea on how long it will take to machine a part and how much to charge for it.
Tooling Cuts Cycle Time in Half
Often, improvements made in the roughing cycle of a job have the greatest impact on the efficiency of the entire project.
This was the case for T3 Energy Services Inc. (Houma, LA), a producer of valve trim for the valve repair industry.
Initially, T3 Energy Services started out with 10 employees manufacturing valve trim for the valve repair industry. Then in the early 1990s the company expanded to offer valve repair and new valve manufacturing. Today, T3 Energy Services employs 75 people and also produces new and remanufactured blowout preventers.
T3 Energy Services needed a tool to increase metal removal rates and reduce the overall cycle time on a project. In the beginning, the cycle time of this operation was 1 hr 18 min. It was the goal of T3 Energy Services to reduce this time and increase its efficiency.
To reduce cycle time on the project, T3 Energy Services contacted its Iscar Metals Inc. (Arlington, TX) representative. A horizontal milling machine and a tool with round inserts were being used to cut the 4340 RC 35 material. The first solution, the Chammill, also had round inserts, and produced good results. T3 still felt increased removal rates were possible. The next test was with Iscar’s Feedmill, an arbor-style milling cutter specially designed for fast metal removal (F. M. R. ). A combination of minimal setup time, increased tool life, and the ability to run at high feed rates made the Feedmill well-suited for roughing applications.
The shape of the Feedmill insert creates a large-radius cutting-edge configuration that allows the tool to be run at high feeds while carrying a large amount of chip load per tooth. The cutter’s trigon-shaped insert enables it to carry up to a 0. 138" (3. 5 mm) per tooth load.
In addition, the insert is designed with a cylinder on the bottom that is seated in a matching hole in the pocket. This enables the inserts to bear higher cutting forces, allowing it to run at higher than normal feed rates.
With this design, the insert is rigidly clamped, relieving most of the stresses that are normally placed on the clamping screw. The cutting forces are directed axially toward the spindle, providing stability while machining. These design features make it possible to remove metal at high rates and increase the overall efficiency of the project.
With Feedmill in place, T3 Energy Services was able to produce the parts needed to complete the job efficiently. Previously, its cutter ran at 550 fpm (167. 6 m/min) taking a 0. 04" (1. 02 mm/min) DOC. The table feed was 33. 6 ipm (0. 85 m/min), producing a 0. 008" (0. 02 mm) per-tooth load.
With the Feedmill, the job was run at 529 fpm (161. 2 m/min) taking a 0. 06" (1. 52 mm) DOC. This produced a 0. 0372" (0. 95 mm) per-tooth load while running at a table feed of 150 ipm. The table feed quadrupled, going from 33. 6 ipm (0. 85 m/min) to 150 ipm (3. 81 m/min) even with the increased DOC. Overall, the machine cycle time dropped from 1 hr 18 min to 36 min.
As an added benefit, tool life also increased from 20 min to 49 min. T3 Energy Services was now able to produce two pieces per cutting edge instead of the half piece per cutting edge it had experienced previously. This added benefit helped to reduce the number of times a tool needed to be changed throughout the day, as well as to reduce tooling costs.
With the newly tooled machine, T3 Energy Services was now able to produce the quality parts the company had become known for while meeting the deadlines required by its customers.
TPM Drives Unmanned Toolmaking
A Total Process Management (TPM) program is driving process improvement and measuring its success in unmanned automated production of toolholders at Seco-Carboloy’s Lenoir City, TN, plant.
The TPM concept, which has been in effect for about 18 months, affects the entire factory, and marshals all the production resources needed to utilize 100% of unmanned time available while maintaining rigorous quality standards.
"Our goal is to create more capacity for volume, and our success is measured in unmanned hours,” explains Randy Jenkins, TPM coordinator.
Seco-Carboloy management understood the potential of automated production for reaching its production goals, and sought a flexible approach to realizing it.
“Because we produce a whole range of cutting toolholders for both machining centers and turning centers, we require a system that is exceptionally flexible and capable of being expanded in the future,” explains Hans Rydvall, manager of engineering and standard production.
After an extensive evaluation process, the Seco-Carboloy team decided that their needs for manufacturing toolholders would be best met with an automation cell consisting of a Hermle C 30 U 5-axis machining center (Hermle Machine Co, Franklin, WI) with storage for 119 tools combined with an Erowa Robot Easy Pallet storage system (Erowa Technology Inc, Arlington Heights, IL) that can hold up to 24 parts.
“We selected the Hermle machine based on its precision and stability,” explains Dave Perry, manager-facility/quality/maintenance. “The heavy-duty trunnion design and the ease of setup and operation enable us to maintain high tolerances in hard materials, and changeover is no problem,” he says.
The Erowa unit offers convenient loading and can be expanded quickly, if needed.
Once the system was in place, the Seco-Carboloy team devised a protocol for preliminary testing. “We selected three different jobs for which we had proved programs, then loaded 24 pallets with eight each of the three parts,” Rydvall recalls.
“We ran the parts during the dayshift without any operator interference. The system performed very well, and we replicated the entire production run at night. Even now, in exceptional cases, if we are running a job toward the end of the dayshift, we load the machine and complete the work on the second shift,” Rydvall explains.
The system is currently running a full 8-hr unmanned shift. After a 3-hr gap in which the Erowa is reloaded and tools replaced on the Hermle machining center, it runs unmanned for another 10-hr shift.
Seco-Carboloy currently runs 22 different parts in batch sizes from 30 to 100 parts, and is adding others. New parts are continuously being integrated as the Lenoir City facility produces both standard toolholders as well as specials.
“Along with the advantages of automation, the system has saved Seco-Carboloy valuable production time,” says Perry. “We’ve cut machining time on some tooling from 7 to 5 min per operation with better tolerances held.”
As might be expected of a toolmaker, Seco-Carboloy paid special attention to the tooling used on the system.
Perry explains: “One of the real advantages of this system is increased tool life. Tool management is critical to unmanned production and, after experimenting, we found that shrink-fit holders combined with the rigidity of the Hermle machining center result in improved tool life. Our own EPB tooling, which is matched to the spindle specifications, is well-suited for these applications.
”Engineering manager Rydvall is similarly enthusiastic about the tool management capability of the system. “The machine organizes all the tooling. When specific programs come up, the tools are grouped closer together to optimize tool change time. Also, when the program is in process, we can measure tool diam and length even when the spindle is in rotation. Any necessary recalibrations are calculated and fed back to the control,” Rydvall says.
Redundancy of tooling is also important. The expanded toolholding capacity of the system ensures that worn or broken tools are immediately replaced. The success of the Hermle/Erowa automation cell in producing toolholders for machining operations has prompted management to define a similar system for indexable drills and turning tools. “Even though we went through an exhaustive selection process before deciding on the present system, we wanted to test it here before committing to a further unit,” says Rydvall.
“The longer we use the system, the more impressed we are with it,” Rydvall says. “In our applications, rotation is key to success as that is how the tool pockets are made. In the Hermle machine, the rotation point is in the center, and the trunnion design guarantees the precision we need.
”TPM goals and quality standards are being met. “We hold tolerances of 0. 02 mm and all quality standards have been met,” says TPM manager Randy Jenkins. “Thanks in part to the new system, we’re at 84% of our Total Process Management goal right now, and expect to be at 100% by the end of the year. ”
Gaging Puts Pedal to Testing Metal
The Custom Engineering (CE) department at Instron Corp. (Norwood, MA) is used to challenging assignments that call for integrating the company’s advanced materials testing equipment for the most demanding customer applications.
Instron systems are used for a wide variety of industries, materials, and applications in R&D, engineering, and production environments. Customers use Instron systems to test everything from the tensile strength of fragile filaments, to the Rockwell hardness of advanced alloys and plastics.
Suzanne de Lemos-Williams, senior mechanical engineer, and her colleagues in the 12-person CE department were enlisted to design and build an automated tensile-testing application for measuring the thickness and width of steel samples in a steel plant, one of the most hostile manufacturing environments.
The solution involved designing a horizontal specimen measuring device (SMD) that would be robust and reliable enough to handle hundreds of large steel parts a day with extreme precision. To avoid extensive user training, the SMD had to be easily integrated into Instron’s automation software to facilitate 24/7 lights-out operations.
“Based on experience with similar systems, we knew that by utilizing high-precision robotics, we could reduce operating costs and avoid human error, a problem brought on by the customer’s old manual inspection process,” de Lemos-Williams explains.
The Gage-Chek, a gage amplifier system from Metronics Inc. (Bedford, NH), was selected for its accuracy, dependability, and affordability. “The Gage-Chek truly became a key piece of the puzzle this application had become,” says de Lemos-Williams. “It delivered +/-5-µm accuracy, real-time go/no-go gaging, a flexible, intuitive user interface, and direct output for SPC.
“And the Gage-Chek gives us four probe inputs-actually half its full eight-probe capacity-enabling the system to handle four measurement probe inputs at once. The eight-probe capability could come into play in future applications, particularly if we need to combine Heidenhain Gages, LVDTs, and HBTs” she adds.
Though the gaging station would become a single element of a highly technical, robotic tensile-testing application, the CE engineers quickly recognized the engineering challenges this SMD presented.
The team faced a number of design decisions, including holding and centering the part to be measured, capturing readings and downloading them automatically to a PC, and building flexibility in to handle the breadth of specimens likely to be tested.
Automated gaging setups such as the SMD require versatile and intelligent features. The Gage Chek actually functions like a microprocessor and provides operators with instant, simplified measurement feedback. Results can be displayed numerically or graphically and archived for process studies such as statistical process control (SPC).
“The four-probe Gage-Chek system fit our gaging, fixturing, reliability, and materials- handling needs,” says de Lemos-Williams.
Here’s how the Metronics Gage-Chek Amplifier works in the Instron-engineered SMD robotic installation. Bar-coded steel specimens are held in a storage rack. A barcode reader determines the proper handling and gaging routine for each specimen, whose dimensions and fixturing requirements can differ widely.
A Fanuc LR-mate 100ib robot picks up the specimen and places it in a pneumatic workstation. The system automatically centers the specimen. Then an anodized aluminum clamp moves in to hold the part in place for measuring. The table indexes to move the specimen to obtain the three required ASTM measuring positions.
The Gage-Chek then goes into action, measuring thickness and width. Next, it automatically computes the values and downloads them to a PC.
The piece is automatically unclamped from the table. In the next sequence, the robot picks up the piece and places it in a universal testing frame, which conducts destructive tensile-testing.
Using Gage-Chek, the entire steel inspection and tensile-testing process now takes about two min vs. the steel company’s former process of handling each part, using a digital caliper to take six measurements for width and thickness, and recording the values manually. In the former scenario, the human error factor alone could seriously compromise quality control.
“Now each rack of 66 specimens can be fully tested in 120-130 min, enabling the company to gage about 300 specimens in an 8-hr shift,” says de Lemos-Williams. “Previously, with the manual process, even on a good day each shift could test up to only about 100 pieces. ”
This article was first published in the January 2006 edition of Manufacturing Engineering magazine.