Featuring a small footprint aand one-piece cast iron bed, Hurco’s?TM8 lathe has a slant-bed design, 10 standard tools?and a?maximum cutting diameter of 12". Its three-jaw, 8" chuck can acommodate workpieces as long as 18.8" with diameters ranging to 2". With XZ axis travels of 8" × 20", the lathe features a 19-hp spindle that can reach speeds as fast as 4,800 rpm. Rapid traverse rates are 750 ipm in the X axis and 945 ipm in the Z axis. Poisitioning accuracy is ± 0.0002", and repeatability is ±0.0001".
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The lathe?is equipped?with the company’s Max control, which accepts both conversational Tungsten Steel Inserts and Lathe Inserts NC programming.?Verification graphics with 3D solid rendering allow users to see cuts graphically before they are made.? According to the company, this saves time and money by avoiding mistakes on real stock.?
Rapidac Machine, a Rochester, New York, contract manufacturer of molding and process equipment for the plastics industry, found itself in a difficult situation attempting to machine a mold from H13 tool steel with a Rockwell C hardness of 56 plus. The customer specified the original mold was to be machined from hardened material so as to be assured the technology was developed for two reconditions of the mold, allowed for in the mold design.
Chuck Day, general manager of Rapidac, called in Tom Schaefer of Harrison Industrial Supply for his recommendations of cutting tools capable of effectively machining hardened H13.Tungsten Carbide Inserts Mr. Day had already tried several manufacturers of cutting tools but was impressed with the Harroun Enterprises tooling that Mr. Schaefer recommended. The Harroun tooling provided the highest metal removal rates and the longest tool life. The remaining obstacle to overcome was surface finish.
Mr. Day went back to Mr. Schaefer and requested his recommendations for improving surface finish without a reduction in tool life or material removal. Mr. Schaefer had recently attended a seminar put on by Richmill USA (Santa Fe Springs, California) on its new High Bred Toolholder. Based upon the data presented at the seminar, he felt this was a good opportunity for Rapidac to test the new High Bred simultaneous face and taper contact design.
Conventional taper shank toolholders fit into the spindle of a CNC milling machine with taper-to-taper contact. Ideally the amount of contact is 95 percent plus, with any mismatch in the small end of the taper. The toolholder is positioned in the spindle with an automatic tool change arm and secured in the spindle with spring pressure furnished through a stack up of Bellville Washers in the center of the spindle. The Richmill toolholder has this same taper-to-taper contact and a pressurized contact with the face of the spindle. Until now, to have dual contact with the taper and spindle face required HSK or custom designed spindles. The Richmill design adapts to any standard 40 or 50 taper spindle. The simultaneous taper and face contact is said to increase the rigidity of the connection between toolholder and spindle by more than 30 percent.
Mr. Day measured the surface finish of his mold prior to using the Richmill holder. The Harroun HIBF cutting tool was yielding a surface finish of 36 microns with acceptable tool life and material removal rates. Once the Harroun ball mill was installed and run in the new toolholder, the surface finish was improved to 24 microns. A minimal amount of hand polishing took the mold to customer specifications. Additionally, tool life was increased from 4 hours to 6 hours per edge.
Mr. Day commented that at first he was concerned the balance design and toolholder design caused a longer tool projection than normal. Once he inspected the surface finish and saw the reduction, he was confident the new design would perform as Cutting Insertsadvertised.
Richmill USA is a subsidiary of Richmill Manufacture Ltd. of Osaka, Japan. Richmill has been supplying workholding and toolholding solutions to automotive manufacturers for more than 40 years.
The Carbide Inserts Website: https://www.estoolcarbide.com/
GWS Tool Group has acquired North American Tool Corp. (NATC), the second bar peeling inserts such add-on acquisition in 2020 for GWS. With the addition of NATC, GWS says it strengthens its reputation as a multi-disciplinary manufacturer of high-performance custom cutting tools.
Located in Northern Illinois, North American Tool is a supplier of special taps, dies and gages. From solid carbide threadmills to high-speed steel taps and thread gages, North American Tool delivers specialized threading tools for applications across multiple industries, including automotive, aerospace, medical and general engineering.
“NATC is an exciting add for us,” says Rick McIntyre, CEO of GWS. “Their customer service model is one of the best in the business.”
“North American Tool is very excited to be joining GWS Tool Group, a company that embodies the attributes that have long made CNMG Insert us successful,” says Curt Lansbery, president and CEO of NATC. “We have no doubt that this move to join GWS will be positive for our associates and will ensure the continued growth of the legacy that we have worked to develop.”
The team at NATC will continue to operate from the Illinois facility as a manufacturing arm of GWS Tool Group, and the company expresses intent toward continued investment in the facility, machinery and equipment, and human resources. Customers of NATC are said to expect continuity of the NATC offering and customer service disposition under GWS ownership.
The Carbide Inserts Website: https://www.cuttinginsert.com/product/16ir-insert/
To accommodate a design change in an automotive part, Machine Tool and Gear (MT&G) of Owosso, Michigan, needed to find a cost-effective way to machine a feature at 90 degrees from other operations. The company soon found that not all tooling could withstand the demands of the application or provide the desired surface finish. However, after purchasing a new cutting tool from Horn USA (Franklin, Tennessee), MT&G was able to cut the part and achieve the desired surface finish without investing in a more expensive solution.
MT&G manufactures more than 112,000 truck shafts each year, among other automotive parts, in its 70,000-square-foot facility. These shafts are produced in a work cell built around a Mori Seiki NH 4000 horizontal machining center. Recently, the design of one of these shafts changed to include a difficult-to-access feature—a flat area that needed to be machined at 90 degrees from other operations.
Manufacturing Engineer Jeff Ochodnicky’s first thought was to use another machine to mill the flats, but that was a major expense the company wanted to avoid. The new machine would need to be located elsewhere in the plant because there would be no room within the existing work cell, and reconfiguring the cell would be a major undertaking. Also, taking the part out of the current cell and moving it to a new machine would require downtime and new fixturing along with additional labor costs to move setup and run the new program.
Instead, MT&G decided to use two 90-degree milling heads to machine the flats. Soon, however, the company realized the tool inserts showed excessive wear and produced an unacceptable surface finish. Working with the insert supplier, the company tried different depths of cut, inserts, spindle speeds and feed rates without TNMG Insert success. The inserts simply couldn’t mill a 1.500-inch-long flat 0.060-inch deep on a shaft using a 0.854-inch-diameter cutter hanging more than 10 inches out of the spindle.
Finally, Mr. Ochodnicky asked for help. He called Phil Horn from local distributor PF Markey, who brought in Brett Kischnick, an application/sales engineer from Horn USA.
According to Mr. Kischnick, the task wasn’t easy, but he was confident he could accomplish it using the right tool. Instead of the staggered-flute-design cutter MT&G was attempting to use, which caused a pushing and pulling during the cut, he suggested using a Mini Mill insert from Horn USA. The Mini Mill would apply all cutting forces downward and free up the cut by using a positive axial helix.
Another hurdle to overcome was achieving a 30-microinch Ra surface TCGT Insert finish without an additional step between two passes—a critical issue for this process. Mr. Kischnick addressed this challenge by eliminating even more cutting pressure by reducing the teeth in the cut from six to three, increasing the surface feet per minute, and making a rough cut first—leaving 0.002 inch for a finish pass. He also moved the finish pass away from the 0.060-inch-tall side wall left from the rough pass. Because multidirectional tool pressure causes a poor surface finish, relieving the side pressure by just a few thousandths of an inch frees up the cut, which provides a better finish, he says. These adjustments produced a 15- to 20-microinch Ra finish without adding a step between passes.
In the end, Mr. Kischnick settled on the final running parameters of 715 surface feet per minute, 0.058-inch depth of cut for roughing and 0.002 inch for finishing, and 0.004-inch IPT for roughing and 0.002-inch IPT for finishing.
“I believed in the 90-degree milling head approach, but I must admit I was beginning to question myself until Mr. Kischnick showed up,” Mr. Ochodnicky says. “It took a while to dial in, but he kept fine-tuning until we achieved the goal. I’d never worked with Horn USA before, but I was very impressed with their knowledge and how they took the time to help solve the problem. As a result, we’ve saved the expense of buying another machine tool and kept additional labor costs out of our process.”
The Carbide Inserts Website: https://www.cuttinginsert.com/product/scmt-insert/
Team Penske is one of the country’s most successful professional automobile racing teams. Dating back to its first race in 1966’s 24 Hours of Daytona, cars owned and prepared by Team Penske have produced more than 420 major race wins, more than 480 pole positions and 28 national championships in open-wheel, stock-car and sports-car racing competition.
Its machining facility in Mooresville, North Carolina, is not a job shop. However, it functions similarly in that it doesn’t produce parts in high volumes, but instead machines small batches (even one-offs) of new race car components that the team’s engineering department has designed to improve performance, such as new suspension, chassis, and steering or brake system components. The shop also machines parts for fixtures and pit equipment, as well as wind-tunnel models, and molds and patterns for composites parts.
Component materials are wide-ranging, too, including aluminum alloys, low-carbon and alloy steels, stainless steels, titanium, epoxy tooling board, and plastics such as nylon and Delrin. The shop uses a range of Mazak equipment, including VMCs, five-axis machines, live-tooling lathes and multitasking Integrex turn-mills.
“Vehicle tungsten carbide inserts weight is critical,” says Matthew Gimbel, production manager for Team Penske. “Over the years, we’ve gone from simple, laser-cut parts to fully machined and pocketed components to minimize overall part weight. It’s also critical to position the weight as low as possible on a car to improve performance. So it’s beneficial whenever we’re able to remove weight from a component installed high on the car and add weight to the weight boxes low on the car.”
Effective roughing operations are key to speed the machining of these parts, because in some cases as much as 95 percent of a billet of material is removed to complete the part. To that end, Team Penske has found that the Tungaloy DoFeed high-feed cutters and TungMeister end mills with exchangeable heads offer key design elements to TNMG Insert perform aggressive roughing operations, thereby speeding the production of new components. In fact, Tungaloy America is a preferred supplier as well as a technical partner for the team’s NASCAR and Indycar racing programs, providing tooling advice to enhance efficiency and accelerate machining for the team’s various manufacturing processes.
According to Tungaloy, the DoFeed’s effective roughing capability is due in part to its geometry that applies the chip-thinning concept. Chip thinning depends on the lead angle of a milling cutter, as is shown in the image in the slideshow at the top of this article. A cutter with a 90-degree lead angle has no benefit of chip thinning, because a feed per tooth of 0.0078 inch (0.2 mm) delivers the same 0.0078 inch (0.2 mm) of chip thickness. For a cutter with a 45-degree lead angle, a feed per tooth of 0.0098 inch (0.25 mm) creates a chip thickness of 0.007 inch (0.178 mm), which enables the feed rate to be increased to reduce cycle time. However, a DoFeed cutter running at a feed per tooth of 0.05 inch (1.27 mm) provides chip thickness of only 0.007 inch (0.178 mm), further reducing cycle time.
DoFeed cutters are also said to offer lower cutting forces. Because a cutter’s lead angle determines the direction of the cutting force, the direction of the cutting force for a 90-degree tool is perpendicular to the spindle, putting increased pressure on the tool. The cutting force for a 45-degree tool is directed toward the spindle, but at a 45-degree angle. DoFeed cutters direct the cutting force nearly parallel and back toward the spindle due to their acute lead angle, which means less pressure is exerted on the tool.
Mr. Gimbel points to a few examples of how the shop benefits from these particular Tungaloy tools. One is a rear suspension panhard bar slider, in which 95 percent of a steel billet is machined away. Roughing time for this component using a DoFeed 1-inch, five-flute tool with multi-purpose grade AH725 inserts, followed by a TungMeister 0.5-inch, two-flute with AH725 inserts, is 36 minutes. The DoFeed cutters produce 10 parts per insert edge and the TungMeister produces five parts per insert edge.
A second is a brake caliper mount machined from 17-4 stainless steel, in which 90 percent of material is machined away. After switching to the previously mentioned TungMeister tool, overall cycle time was reduced by 50 percent, because it saved 20 minutes of roughing time per part. In addition, the tool provided effective chip control when machining deep pockets to eliminate chip packing. “Even with deep pockets, we have the confidence to run these parts unattended, because we know that the tools will last,” Mr. Gimbel says. “These tools also enable faster cutting-tool changes, because only the cutting head is replaced, not the entire tool.”
Another unattended machining example is a steel engine mount in which 82 percent of a billet of material is removed. This part has a unique geometry in that no exterior surfaces are orthogonal or parallel to one another, and its five holes are kept within 0.003 inch of each other. Although five-axis machining is the most efficient way to maintain the hole-location tolerances and remove the majority of the material, cutting speeds were a concern because of long tool lengths needed. Fortunately, the low cutting forces generated by the DoFeed tools (2-inch, five-flute and 5/8-inch, two-flute DoFeeds with AH725 inserts) enabled the shop to maintain cutting speed during the roughing cycles, even with extended toolholders. “In addition, tool durability, and predictable and consistent tool wear again enables us to run our shop lights-out.” Mr. Gimbel says. “We’re confident that we can leave the machines running after hours.”
Team Penske benefits from other Tungaloy tools, too. “Tungaloy offers a better range of boring bar sizes in its Mini Force turning line, so we were able to expand our solid carbide coolant-through boring bar selection while reducing the number of inserts in inventory, since the boring bars used the same type,” Mr. Gimbel explains. “Plus, the cost per cutting edge is 7 percent less than the four-sided inserts that we were previously using.”
The Carbide Inserts Website: https://www.cuttinginsert.com/product/sngx-insert/
