A combination of a robust design, thermal compensation and scales on axes in SNK’s Nissin HBM BHP130-3.5 series horizontal boring and milling machine is designed to produce high cutting accuracy.
The machine features a cast iron construction, scale feedback of the worm and wheel, and large worktables with nine T-slots to simplify work fixturing. Extra-wide solid box ways, finished with the company’s “mirror surface finish” BTA deep hole drilling inserts technology, accommodate large parts, and oversized ballscrews on all linear axes provide precise positioning in demanding machining conditions.
A 5.1"-diameter boring spindle performs at speeds ranging from 5 to 3,500 rpm and travels within a 7.08" milling spindle to provide a full 90.5" stroke. A built-in rotary table provides a fifth axis of operation and positioning control within 0.001 degree.
To further enhance precision, thermal growth sensors are positioned around the spindle casting and bearing to continually read temperatures (within microns) in five areas. This reduces the risk of false readings and ensures accurate Carbide Drilling Inserts compensation, the company says.
The machine’s 70.8" × 98.4" table can accommodate loads as heavy as 44,000 lbs. X-, Y-, Z- and W-axis stroke measures 138" × 98" × 63" × 27.5", respectively, and X-, Y-, Z- and B-axis scale feedback is standard. A 60-tool ATC features a pneumatic pedal to ease tool loading and unloading.
As part of what is arguably the most advanced fighting force the world has ever seen, U.S. troops depend on high-tech weaponry and equipment to complete their objectives while minimizing risk to themselves and civilians. However, while new missile systems, robots, unmanned aerial drones and other high-profile advances have changed the face of modern warfare, devices that may seem trivial by comparison can also make a big difference on the battlefield.
One such device has been saving lives in Iraq and Afghanistan for two years. The ATSS MKIII and MKIV sight and illumination mount systems allow soldiers to equip heavy, vehicle-mounted machine guns with the same optical sights and aiming devices used on their M4 rifles and other personal munitions. Rather than a big name in defense manufacturing, the mount was developed by a an entrepreneurial, husband-and-wife team with a good idea and a CAM package that allowed them to make the most of their single, veteran milling machine.
Lowell and Ardis Kenney are the owners of Eagle View Research Center, a Shelton, Washington-based prototype shop. Without the floorspace or budget to purchase a new machine, the couple turned to their CAM supplier, Surfware, to provide a solution that would allow their aged VMC to cut steel more efficiently. The software developer’s TrueMill CAM engine enabled the Kenneys to ramp up speeds, feeds and metal removal rates while avoiding tool breakage, leading to significant cost and cycle time savings. "I may be cutting my own throat, but I know people who adapt TrueMill technology will be able to compete better than those who don’t," Mr. Kenney says.
Eagle View was founded in 2001, when the couple purchased a 1992-model VMC along with the Surfcam 21/2D CAM package and began making aerospace parts from their home. When the terrorist attacks of Sept. 11 sent the airline industry into a tailspin, the Kenneys reestablished their business as a research and development shop. Dabbling in work ranging from outdoor recreation equipment to firearm components, the couple began to design prototypes, figure out the best way to machine them and contract with local machine shops when products were ready for full production.
The business took a decided change when the Kenneys’ oldest son returned from his first tour as an Army captain in Iraq. He brought with him a series of sketches he’d drawn on napkins depicting a mount designed to add high-tech sights and aiming devices to the Browning M2HB .50-caliber machine gun. Commonly mounted on vehicles such as the HMMWV, Cermet Inserts Bradley armored personnel carrier and Abrams M-1 tank, this weapon is effective against everything from infantry to light vehicles and even aircraft. The gun’s versatility has made it a mainstay in the U.S. armed forces that has seen service in every conflict since the early 1920s.
Mr. Kenney himself had used the M2HB during his service in the Vietnam War, when standard practice was to shoot in the general vicinity of the enemy and then "walk" the rounds into the target. However, the urban battlefields of Iraq and Afghanistan present challenges unlike those faced in most other conflicts, a fact Mr. Kenney’s son understood all too well. "Dad, we can’t range in the gun like you used to," he explained to his father. "We can’t ricochet bullets in the streets of Mosul or Baghdad and expect to win friends—we Coated Inserts need to be on target every time."
Once Mr. Kenney had machined a suitable prototype, his son challenged him to make the devices for the whole Army. That became the start of a new division that the Kenneys call Advanced Tactical Sighting Systems (ATSS). However, the shop’s VMC had difficulty cutting the large quantities of CR 1018 steel required to make enough prototypes to market the sight mount. Most machinists would consider that old workhorse to be a light production machine, even for cutting aluminum, Mr. Kenney says. "I was trying to push things as hard as possible, and I was breaking lots of tooling," he explains.
However, after asking Surfcam technical support for help with a programming problem, Mr. Kenney was introduced to a product that could push his old VMC to new limits. The applications engineer asked why the shop was not using TrueMill, a CAM engine designed to create more efficient tool paths. Mr. Kenney was skeptical—he had heard of the software before but thought it was designed primarily for big shops using fast new machines with large memories.
When Surfware provided some feeds and speeds for use with the program, Mr. Kenney set up a piece of 5/8-inch-thick steel used to produce one of the sight mount’s components, an A-frame-style tower that typically took between 17 and 20 minutes to cut. Mr. Kenney reprogrammed the VMC with TrueMill and set up a DNC drip feed so the machine’s limited memory could accommodate the part program. He was so sure he would break a tool that he left a worn cutter in the machine. With the coolant turned off and a hand hovering over the panic button, he started the machine and waited for the 1/2-inch, TiAlN-coated carbide end mill to break.
He soon realized that the cutting action had never sounded better, and long, thin chips poured from the cut. Sliding the door open and cleaning the pocket with an air nozzle revealed a smooth side wall cut to the full 0.625-inch depth. The spindle load meter had not gone above 25 percent, and Mr. Kenney says the cutting pattern was different than anything he had ever programmed. After a week of testing, he applied higher feeds and speeds. Although these more aggressive settings pushed the load meter to 50 percent at times, Mr. Kenney experienced no crashes or tool breakage and finished the part in about 9 minutes. "I wouldn’t have even cut aluminum like that a year ago—TrueMill just hums," he says.
Most CAM systems generate tool paths based on a given stepover value and the shape of the geometry being machined. However, with this method, the tool’s engagement with the material can radically and rapidly change when it encounters an inside corner, the developer says. This greatly increases the load on the tool and the tool’s temperature, either of which can result in chatter and other undesirable cutting conditions.
Rather than geometry, TrueMill tool paths are driven by engagement angles—that is, the portion of the cutter’s periphery in contact with the material. Thus, the shape of the geometry doesn’t dictate the flow of the tool path. Rather, each cut is conducted in a way that allows the next cut to proceed at the desired engagement angle. Though the part shape is ultimately produced, it doesn’t become apparent until the final passes of the tool.
TrueMill manages tool engagement by varying stepover according to the toolpath radius and in-process material boundary. In addition to ensuring that the tool is never over-engaged, the software ensures that spindle speed, feed rate and depth of cut stay at set, user-defined limits. According to the developer, keeping all four of these factors constant reduces variation in not only the tool’s load and temperature, but also chip thickness. This allows for more aggressive cutting parameters and a higher, more consistent metal removal rate.
Powering their Surfcam CAM software with TrueMill has enabled the Kenneys to increase depth of cut from 0.2 inch to 0.6255 inch, spindle speed from 2,000 to 6,000 rpm, and feed rate from 15 to 60 ipm. The resulting improvements in cycle time have significantly reduced costs—the aforementioned tower component now costs only $9.75 to produce, compared with $18.42 before TrueMill. "I’m cutting more steel faster and more accurately, and the results are better than ever," Mr. Kenney says.
Moreover, once they determine the best way to machine a part—whether a customer-requested design alteration to the ATSS sight mounts or an entirely new product—the Kenneys can provide TrueMill-generated programs to the job shops they use for mass production. The engagement-driven tool path’s benefits are amplified on these shops’ newer, more sophisticated machines, enabling Eagle View to demand more from its business partners and speed delivery to customers. As a result, the Kenneys are currently working to secure an order for as many as 20,000 sight mounts for the Department of Defense and are considering a shop expansion.
The oil and energy business continues to grow. To reach deep oil reserves, drilling companies use a series of 40-foot lengths of pipe connected by couplings. The ID, OD and threads of those machined couplings must be accurate so that the pipes don’t leak. Pipe leakage is especially problematic at significant depths.
Manufacturing couplings has traditionally been a manual process. Large companies that make couplings do so by manually loading pipe into older types of machining equipment. The heavy couplings are difficult to for operators to load and chip control during turning and threading operations is challenging.
Until recently, no one had developed an automated system dedicated to manufacturing couplings. Gayle Vollmer, Okuma director of technical resources, suggests the reason is because oil coupling producers are running at full capacity with their existing equipment and have little time for process development. “There’s also a substantial cost factor in putting together a production cell for research and development,” Mr. Vollmer says. “Partners in THINC has not only the products and cell design expertise, but also experience helping shops that serve the oil industry.”
In fact, Okuma and the Partners in THINC have created an automated coupling production cell that is scheduled to be available in August 2007.
The oil industry uses two primary types of couplings: “API” couplings for relatively shallow oil wells and “premium” couplings for deep wells (used mostly for off-shore Carbide Turning Inserts drilling). Demand for premium couplings has dramatically increased. After much research, Partners in THINC decided the time was right to develop a cell that offered a completely automated coupling production process to help meet that demand.
The cell was built and tested at the Partners in THINC facility in Charlotte, North Carolina. After experimenting with various tools, coolants, coolant pressures and machining practices, the Partners were able to solve the primary problem of chip accumulation during the turning and threading operations.
The automated manufacturing process begins with a FANUC overhead gantry robot that loads a double-length coupling blank in and out of the machines. This eliminates the need to have operators lift the heavy 9-5/8-inch-diameter workpieces. The gantry design also offers increased flexibility Helical Milling Inserts while saving valuable floor space. During machining, the blank is cut in half, eliminating a secondary sawing operation.
Using Kennametal, a Partners in THINC tooling partner, the roughing and finishing operations for coupling ID and OD are performed on a four-axis Okuma LOC-650 oil-country lathe. This lathe also performs the cutoff operation that separates the blank into two 10-inch-long coupling pieces. The pieces then move down a conveyor to an Okuma V80R vertical turning lathe (VTL). The vertical spindle orientation assists in evacuating chips during turning and threading operations. Both machines are fitted with a Schunk “oil country” chuck.
The chips produced during threading operations fall and flow away from the workpiece thanks to the V80R VTL’s modified tooling adapter and ChipBLASTER high-pressure, high-volume coolant system. Coolant flow from precisely directed nozzles helps break up the chips and flush them out of the machine. After the threading operation, the workpiece is conveyed out of the cell and delivered to a measuring station, where a Marposs gage inspects its threads and diameters. The cycle time to turn, thread and deliver a completed coupling out of the cell is only 11 minutes.
This cellular production method allows complete OD turning in one operation. This helps meet high-precision threading requirements by avoiding the undesirable blend line that occurs with a two-part operation. In addition to increasing production speed, the cell eliminates the need for a 2-minute sawing operation.
Considering the increase in oil drilling activity, this timely Partners in THINC solution for automated production of drill couplings will have far-reaching effects in the oil industry.
The Carbide Inserts Website: https://www.estoolcarbide.com/product/factory-wholesale-cnc-lathe-cutting-tools-solid-carbide-inserts-milling-inserts-bdmt11t308er-jt/
Autodesk’s PowerMill 2019 CAM software includes developments designed to enhance existing functionality for high-efficiency machining.
This version includes additive manufacturing strategies and simulation tools designed for hybrid machines. It generates safe and efficient tool paths to drive directed energy deposition (DED) processes that use wire-fed or powder-blown hardware. Specialized three- and five-axis programs enable building entire components from scratch. It can also apply localized features or surface Cutting Carbide Inserts coatings to repair or enhance existing parts.
For five-axis programming, the software includes improved collision avoidance tools. An automatic tool-axis tilting method simplifies programming, helping to generate smooth and safe five-axis motion for all model shapes and toolpath types.
Vortex, the high-efficiency roughing strategy, now includes a “from stock” option based on the company’s adaptive clearing technology. It creates tool paths with offsets based on both the shape of the part being produced and the stock being milled, resulting in efficient tool paths with shorter machining cycle times and fewer tool retractions.
For 2D machining, the software improves workflow for defining open-sided pockets and bosses. The existing 2D Carbide Drilling Inserts tool paths recognize these features, automatically positioning tool entry and exit points to avoid overloading cutting tools. It also enables users to create 2D features based on a selection of surface.
ViewMill, a stock simulation tool, now includes a “remaining material” shading mode. This helps programmers to identify areas of unmachined stock to ensure parts are fully machined before removal. The shading mode automatically identifies the maximum amount of stock left on a simulated part and provides dynamic slider bars to visualize the distribution of stock.
The software also includes a “setups” feature that enables programmers to better manage the synchronization between tool paths and NC programs. It also provides functionalities for parts with multiple fixture offsets.
Four years represents an eternity in the life of metalworking tools. In that time, TP Engineering (Bethel, Connecticut) has milled a mile of aluminum without changing the inserts on a Kennametal three-cartridge, 0-degree lead, 3-inch polycrystalline diamond (PCD)-tipped high-velocity face mill.
TP Engineering, a designer and manufacturer of Harley-Davidson aftermarket motorcycle engines and related components, is using PCD milling to finish engine cases, oil pumps, rocker boxes, inner and outer primary engine covers, and transmission cases and covers.
"We couldn’t be happier with the performance of PCD milling," says Tom Pirone, TP Engineering’s president and founder. "To this day, I find it amazing that we have never changed inserts."
In this application, TP is using PCD to work on 6061T6 aluminum and 356 aluminum, a difficult-to-machine material that it mills on a Mori-Seiki SH-400, a Mori-Seiki SH-403 and two Okuma MX 40 HA horizontal machining centers.
"The secret to the PCD face mill is in the design," says Gerry Dobrynski, the Kennametal field sales representative who services the TP Engineering account. "These lightweight but sturdy milling cutter bodies are engineered to best utilize the cutting power of the PCD adjustable cartridges that are secured to the cutter body with socket-head cap screws. Each cartridge is tipped with super-hard PCD (KD100 grade) that enables faster speeds, excellent tool life and superior surface finishes when compared to carbide or high speed steel (HSS) tools."
TP Engineering’s use of PCD high-velocity face mills is enabling the company to mill 10,000 sfm at 140 ipm.
Besides increased tool life and decreased cycle time on the engine case from 1 hour to 24 minutes, Mr. Pirone is also pleased with the mirror finish that results from a Kennametal PCD face mill. "The surfaces achieve a superior finish with a phenomenal consistency that I didn’t expect when I began using PCD, and I’m sure that it influences Harley-Davidson owners to buy our products."
TP Engineering replaced a carbide end mill 6 years ago with helical and router style Kennametal NGE-I end mills. The mills use six KC725M inserts for milling steel and six KC510M inserts to mill aluminum on a Mori-Seiki SH-400 horizontal machining center to perform profile milling on connecting rods, engine cases, inner and outer primary engine covers, oil pumps and rocker boxes.
The significant values for TP Engineering’s use of an NGE-I end mill are 10,000 sfm at 120 ipm for milling aluminum and 500 sfm at 20-40 ipm for milling steel. By using NGE-I, TP has tripled productivity and tool life while improving the smoothness of surface finishes by a factor of three.
"TP Engineering has realized those quantitative and qualitative improvements because the NGE-I offers positive chip forming geometry, which results in free cutting action and lower cutting forces," says Brian Hoefler, Kennametal’s NGE product manager.
"NGE end mills are versatile and can be used for machining shoulders, slots, contours and facing," Mr. Hoefler continues. "These features, combined with the latest Kennametal ‘M’ milling grades, give users productivity advantages that are crucial to the milling requirements of many jobs that require the production of high-quality parts in record time."
Adds Mr. Pirone, "By getting 40 parts per insert edge instead of 12 or 13, having each insert cost us $12 a piece instead of $60 and having such responsive customer application and field service support, Kennametal provides the kind of value we wish all of our suppliers could give us."
Mr. Pirone has also integrated Kennametal drilling tools with his company’s manufacturing operations. For the past 2 years, TP Engineering has been using KSEM APKT Insert Sculptured Edge High Performance modular drills on an Okuma MX-40 HA horizontal machining center to drill deep holes in rocker arms made of 4140 steel that has been heat treated, machined and then hardened to 32-36 HRC.
Using a drill body that is 5 inches long and a carbide blade in grade KC7215, TP is making 400 holes per blade that are 3.600 inches deep with a diameter of 0.630 inch.
"Because KSEM’s design propels the drill into the workpiece at a tremendous penetration rate, while breaking chips effectively and maintaining stability, the user is ensured of getting precise, close-tolerance holes faster," says Kennametal’s Mr. Dobrynski.
To make holes in the aluminum casting of the engine crankcase, TP is using a 5-inch drill body and a grade KC7235 blade to drill more than 2,000 holes (and counting) Face Milling Inserts at a depth of 2.01 inches with a diameter of 1.125 inches. Kennametal performs factory reconditioning of the blades.
TP Engineering’s use of Kennametal’s holemaking know-how extends to the Dynapoint Triple-Flute (TF), a solid carbide drill that TP is using to make small-diameter holes in engine and transmission cases made of 356 and 6061 aluminum. With Dynapoint, TP Engineering is making 24,800 holes per body at 0.51 second per hole. A tool that TP formerly used had an output of only 1,000 holes per drill body at 4 seconds per hole.
With three flutes, the sculptured edge drill point creates a smooth transition from the major cutting edge to the center of the drill, eliminating stress peaks and allowing the drill to actively cut metal over the entire cutting edge.
Compared to conventional drills, which are ground with flat chisel points that will push and tear the metal, the sculptured edge design is said to allow the user to handle increased chip loads for faster penetration rates and greater productivity.
Over the past 4 years, Kennametal has helped TP Engineering reduce its cost per part, decrease cycle times and increase tool life.
