HORN USA is proud to present the new 32T system for grooving and parting off on Swiss-type lathes and smaller fixed-head lathes. With a precision-sintered grooving insert and central clamping screw, the tool system offers high changeover accuracy for the cutting insert and direct entry into the insert seat of the tool carrier.
Additionally, there is no need for clamping elements, which may have a detrimental effect on chip flow. The screw head of the clamping bolt does not introduce interfering contours and therefore permits both grooving on a collar and parting off directly at the spindle.
The grooving insert can be used as a neutral insert, and as both a left-hand and a right-hand insert.
The 32T system completes HORN USA's portfolio of triple-edge cutting inserts by offering a solution for smaller-scale applications. By adding the new system to its range, the tool manufacturer is responding to customer requests for a triple-edge cutting insert system for Swiss-type lathes and other smaller turning machines, in particular in applications where space is at a premium.
The precision-sintered 32T insert is secured to the holder with a central screw, removing the need for additional exterior clamping components that negatively affect chip flow. Available in 2 and 2.5 mm (.079 and .098") widths with maximum depth of groove up to 4 mm (.157"). For grooving operations, the inserts are available with both straight and full-radius cutting edges.
HORN USA offers the indexable insert with a 15-degree chamfer for parting off. A cylindrically ground chip-breaker geometry makes for reliable chip removal.
The tool carrier is designed as a square shank measuring 10 x 10 mm or 12 x 12 mm. Both versions feature an internal coolant supply and are available in both left-hand and right-hand designs.
Case Study: E-Z Burr
Skyway Precision Inc. is a comprehensive CNC World Class Machining operation, located in Plymouth Michigan. It is Skyway’s commitment to provide their customers with experienced machining processes and quality products that are delivered on time with an industry competitive cost. Established in 1968, Skyway prides itself by making their mark on the preferred supplier list of many major global manufacturers and has forged a reputation as an industry leader in the production of machined components.
The Burring Problem:
After working with Skyway on several projects, they asked E-Z Burr to provide a solution to a deburring challenge to reach the backside of a large 80lb component. The Nodular Iron component is an 11.6 inch Hub with 22 holes, 10 @ .425 diameter and 12 @1.093 diameter.
Skyway was removing the 80lb hub from the Hyundai-Kia Hi-V50D machine, and placing it on the workbench to manually deburr the rear of the holes by using a countersinking tool in an air drill. This method proved to not only be cumbersome, but also time consuming and costly.
The weight of the hub required heavy lifting and positioning while performing this secondary operation by hand on the workbench. The extra handling required further man-hours and was a challenge in maneuvering.
In addition, the countersink tool was expensive, and the life of the tool was very limited. The tool would wear quickly and required re-sharpening or replacing often. This extra operation was an added cost to the machining process.
The E-Z Burr Carbide Series Tool offered Skyway a variety of options designed to do the rear of the holes while the hub was still in the machine.
“While we have a standard selection of diameters and lengths available off the shelf, we designed a special 9” long tool for this unique application. “The tool was tested at 550 RPM @ 8.8 IPM (1.087 hole), to accommodate their specifications”, says Robinson.
“This gives them the ability to deburr the backside of the hole efficiently while the hub remains in the machine.”
For the smaller holes on the hub, a standard length tool at 1750 RPM @ 11 IPM (.425 hole) is used to deburr both the top and bottom all in one economical pass. Skyway prefers to use the more aggressive E-Z Burr carbide insert that is also a standard option. The increased angles and positive cutting features provide just the right amount of pressure and engagement to produce the desired chamfer.
The introduction of the E-Z Burr Tool to the process eliminated the need to remove the part from the machine to do the rear of the holes. The danger and additional manpower was dramatically reduced with the new process.
In addition, the time spent using the countersinking tool and the cost associated with the tool were eliminated and resulted in more profit to the bottom line.
Eliminating the need to remove and transfer the part created a safer working condition for the machine operators and a better job quality allowing the operator to focus on performance while meeting production schedules.
This solution led to productivity, saving Skyway 15 to 20 minutes per part. While the countersinking tool would last a day or two, the E-Z Burr carbide insert proved to run a month before the need of replacement. The tool itself remained in the machine while the insert was being replaced adding to the ease of use and gained efficiency in manufacturing.
This process then led to further engineered improvements by using a short pilot drill to start the hole and chamfer the top of the large holes. The pilot hole eliminated the “walking” and breakage problems and prolonged the life of the expensive long drill to perform its function.
“E-Z Burr prides itself on more than just providing superior deburring tools. We get involved with our customers to solve production problems where deburring parts are an important measure in the final product,” says Robinson. “Problems should not be a roadblock and time is a precious commodity in production. We have the ability to accommodate tight timelines of days or weeks. The particular tool we customized for Skyway was designed and delivered in less than 2 weeks.”
Getting coolant through the toolholder and to your cutting tool can be accomplished in two ways with Parlec and Techniks toolholders. Coolant is delivered from the spindle by two methods:
Through-Flange/ DIN B Coolant Delivery
Combined with solid retention knobs "Through the Flange" holes go through the flange to deliver the coolant from the spindle.
This is sometimes referred to as "DIN B" or "Form B".
Through Flange/ Form B is an available standard for many tools and available as a standard modification for most toolholders.
Form B convertible or AD/B (BC) is available in many sizes. The AD/B (BC) style can be used as either through the spindle , as supplied, or converted to Form B, through the flange. Flange entry is enabled by removing two screws
When discussing Screw Threads, it may be helpful to understand a little of the history behind them.
Let’s start with helical forms. Records dating to around 250 BC establish that it was Greek mathematician Archimedes who explained the mechanical principle of the screw as a form of wedge. He went on to formulate the mathematical characteristics of a helix. This was a precursor to the invention of the “water screw”, which provided a means to move water for irrigation, and as a method for ships to evacuate bilge water.
It is apparent that other great civilizations contributed to the development and use of this tool, but the Greeks apparently had better people in the PR Department, as they get most of the historical credit. There is some evidence the water screw may have been used in Egypt before the time of Archimedes. The helical screw form was also used in presses by the Romans to make olive oil and wine, and later in printing presses like the first used by Gutenberg in the mid 1400’s.
As time went on the screw-form used as a wedge became an alternative to bindings and rivets as fasteners. Even though it offered the advantage of faster assembly and disassembly, manufacturing methods were primitive. Mating threads were matched to each other by hand, one at a time. Not until the 17th Century, with the development of lathe technology, did manufacture of precision threads become possible.
Even then, there were no standards for thread dimensions or form to assure performance and interchangeability of parts produced. Precision threads were being used in design of measuring instruments and manufacture of new technology. Railroads were being built and factories required new machines for mass production of goods. Increasing demand required a solution. Steps toward solving that problem would not come until the next century.
Joseph Whitworth and William Sellers - Two to Lead the Way
In 1841, a British engineer named Joseph Whitworth devised a set of standards for screw threads to address the need for uniformity and quality of performance in threaded parts. These standards prescribed a flank angle fixed at 55 degrees and standard thread pitches for given diameters.
In 1864, an American engineer named William Sellers presented another set of thread standards. Sellers proposed a 60-degree flank angle with flatted thread crests and roots. Like Whitworth’s standards, his proposal assigned standard thread pitches (threads per inch) for given diameters.
The British standards were accepted worldwide, including the United States, but Sellers thread-form was easier to manufacture. Measurement was also simpler, as the form was based on the angles of an equilateral triangle. Some would argue the absence of radius on the thread crest and root left a weaker thread. Years of use would prove Seller’s thread-form more than adequate for the vast majority of applications.
Even today, both of the thread-forms described above are in use. New standards have been assigned to address ever expanding uses. The addition of specialized forms like Acme, buttress, ballscrew, worm thread, and self-locking thread have been refined for function- specific use. There are threads for assembly of parts, fastening, creating motion, measurement devices, lifting, and fluid and gas sealing. The uses are almost endless.
There is a screwdriver in every house and business. Isn’t that a great indicator of the impact of screw threads on the world? Although most forms have been assigned standard specifications by governing bodies, there is no limit placed on the imaginations of engineers to fine-tune fit and function as well as to find new uses for the simple helical form developed centuries before.
At IMTS 2018, HORN USA presented two new developments in the area of whirling processes.
The JET Whirling System is the first whirling tool to feature an internal coolant supply. This whirling system offers optimized cooling directly at the cutting edge and was developed by HORN USA in conjunction with W&F Werkzeugtechnik.
Another innovation is the High-Speed Whirling Technology, which delivers high levels of productivity. In this process, the speeds have been specially adapted so that preturning and thread whirling can be carried out in parallel using a single work operation.
Through the JET Whirling process, HORN USA is demonstrating its expertise in the area of thread whirling. As part of a collaboration with W&F Werkzeugtechnik in Großbettlingen, experts from both companies have jointly developed a whirling system with an internal coolant supply.
By cooling the cutting edges directly, this system enables long tool life to be achieved. What’s more, when used in conjunction with the stable whirling unit, the system achieves better surface quality on the workpiece. Thanks to the patented W&F interface with its coordinated contact system for the tapered and planar surfaces, the whirling head boasts a high changeover accuracy and is easy to change with just three screws. The internal coolant supply reduces the risk of chip build-up between the cutting inserts.
It takes less than a minute to change the whirling head on the whirling unit interface. This interface offers a radial and axial run-out of 0.003 mm. The maximum speed is 8,000 rpm. The whirling heads are available with type S302 triple-edged indexable inserts or with type 271 double-edged inserts. The cutting edges are available with diameters of 6 mm, 9 mm and 12 mm. The interfaces for adapting the whirling unit are available for all standard Swiss-type lathes.
HORN USA is proud to present another new technique in the form of high-speed (HS) whirling. This technology is being exhibited in collaboration with machine manufacturer Index-Traub. High-Speed whirling boosts productivity significantly by performing the turning and whirling operations in parallel. With this technique, the speed is high enough for a turning process to be carried out prior to whirling.
The turning tool, which is located upstream of the whirling tool, reduces the volume of material that would otherwise have to be removed by the whirling tool. This enables longer tool life to be achieved and improves surface quality. The whirling heads are very similar to conventional ones. The only difference lies in the geometry of the cutting inserts. Single-start and multi-start threads can be produced using just one cutter unit.
Highly Productive Technique
Thread whirling is generally used in the production of bone screws. In this application, the whirling head rotates at high speed as it travels over the slowly rotating workpiece. The whirling head is set for the required lead angle of the screw. The workpiece is fed axially and as this happens the whirling tool cuts the thread.
Due to the high level of screw quality required, special attention must be paid to precision and surface quality when it comes to whirling tools. In addition, special materials are used for bone screws to ensure that the body is able to tolerate them when they are implanted. These include stainless steels, titanium, or cobalt-chromium alloys, although the disadvantage of these materials is that they are difficult to machine.
Therefore, expertise and experience are required if these materials are to be machined productively. For instance, the carbide substrates, coatings, and cutting edge geometries all have to be tailored to the application concerned.
HORN USA offers further whirling technologies in addition to its JET Whirling and High Speed Whirling solutions. Of these, the most universal technology is the standard whirling method. The whirling head can be connected to any whirling unit. For faster whirling head and insert changes outside of the machine, HORN USA has developed a modular whirling system.
Thanks to the precision interface, there is no need to readjust the whirling head once it has been removed from the machine. In addition, the spacer rings make it possible to adapt the whirling tool to different interfaces. With HORN USA Turbo-Whirling, high productivity is a sure thing. The cutting division between the roughing and finishing inserts reduces the load on the whirling tool’s profile cutting inserts. As a result, the system offers faster process times and lower tool costs.
Tech Tips: Decatur Diamond
CVD coated diamond tools are a perfect match for machining carbon fiber composites (CFC) such as carbon fiber reinforced polymer (CFRP). The very abrasive characteristics of composite materials severely limit the life of both carbide and PCD diamond tools. Tools with diamond on the surface wear longer and have a lower coefficient of friction. These characteristics provide substantial benefit to machining operations.
Because CVD diamond tools last 10-50 times longer than carbide tools, and 3-4 times PCD diamond tools they:
The low friction of CVD diamond tools permit using speeds higher than both carbide and PCD – again contributing to higher productivity – with no degradation of the surface quality or tool life. The consistently sharp edge and lower friction allows delicate, thin wall sections to be machined quickly and precisely.
The sharp and long wearing edge also puts lower stresses on the part, fixturing, and equipment. Since CVD diamond has no cobalt binder to break down or abrade away they offer the longest possible tool life.
Carbon fiber composites can be machined successfully with diamond coated endmills if resin melting and chip evacuation are carefully controlled. Observance of the following guidelines should yield tool lifetimes of approximately 10 times the equivalent carbide tool.
Speeds and feeds must be adjusted to avoid melting or softening the resin in composite materials. This means that feeds must be 0.001” ipt or greater with larger diameters and speeds should be kept at 400-500 sfm for most types of materials.
As the depth of cut increases the cutting speeds should be reduced to below 400 to minimize heat buildup in the chips. For shallow depths of cut, feeds can be up to 0.010” ipt for 1/2” diameter tools. Maximum feed rates are a function of the depth of cut and limited by the tool strength for a given diameter.
For slot depths exceeding more than 1/2 the diameter of the endmill the evacuations of chips from the slot becomes extremely important. Failure to adequately remove chips can cause breakage of the carbide under the diamond film on the flute edge and subsequent catastrophic failure of the tool.
The use of 2-flute tools and moderate-to-high feed rates is highly recommended to insure good chip flow. Air flow into the cut and vacuum evacuation of chips from the cutting area are also recommended. Additional life improvements can be obtained by using a corner radius or ball end tool for the initial cut and then following up with a square end tool with a much shallower cut to achieve the final dimensions.
For side cutting applications there is also an issue with chip evacuation if the radial depth of cut exceeds 1/4 of the tool diameter for a 4-flute tool or 2/3 the diameter for a 3-flute tool. Maximum tool life and production rates are generally achieved with 2-flute tools operated at high feed rates for most side cutting applications.
Sidecutting Machining Parameters:
Recommended parameters for sidecutting are listed in the following chart for various flute configurations. Recommendations are based on a cutting speed of 400-500 sfm and a diameter of the tool greater than or equal to the material thickness. Larger radial depth of cuts are possible if the material is substantially thinner than the tool diameter.
Slotting Machining Parameters:
The recommended parameters for slotting are listed in the following chart for various flute configurations. Recommendations are based on a cutting speed of 400-500 sfm and a full width slot which does not penetrate the full thickness of the material thickness.
See the sidecutting chart above for slots which penetrate the full material thickness.
Note: VDOC’s greater than 100% of the tool diameter are listed for informational purposes only and are not recommended for normal operation.
Tech Tips: Hannibal Carbide
If you are ordering a special drill, here is the nomenclature you should be familiar with when preparing to write your specifications.
A manufacturer of spinal implants and surgical instruments achieves immediate results in a switch from rotary broaching to hex broaching.
Small changes can make a big difference. Shopfloor personnel who have been in the business for a long time usually know this. A new CNC machine or a complete overhaul of procedures isn’t necessarily the only way to make a substantial impact on the shop’s output. And it’s a good thing. Sometimes a simple change in tooling can be just the ticket to the next level of success.
When a shop is a relative newcomer, resources might not yet be available to invest in additional machine tools, and processes are often still being established. But even when a shop is young, it’s still often the beneficiary of well-trained and even well-established operators and engineers, along with knowledgeable suppliers. And these individuals are the right people to look toward for instituting changes that will make a difference.
A Medical Upstart
Amendia (Marietta, Ga.) opened its doors in 2008 with a mission to design and build spinal implants and instrumentation in the spinal device market. The company designs and manufactures its own cervical and lumbar implant devices and markets them to its distributors and direct sales force, who service spine surgeons at hospitals or surgery centers.
The company currently has about 65 employees, all but two of them work the first shift. Those two employees work the second shift, and the third shift is totally lights-out. Unattended operations are continuous throughout the night, 6 days per week. The well-maintained shop floor has a lineup of Mazak Integrex and Multiplex machines that are used to manufacture implants such as interbody devices made from PEEK.
In the Swiss area of the shop floor, four Nexturn SA-20e Swiss machines, two SA-20b machines and one SA-32e crank out hundreds of lumbar and cervical screws per day, along with other components needed for the implant system. “Several things are going on to make up the entire system that is used in surgery,” Application Engineer Steve Selvia says. “You have a screw, a tulip, a saddle and a set screw. Cycle times and quantities vary, but we run these around the clock in the Swiss Department.” Horn USA supplies much of the tooling in this area.
All of the parts produced in the Swiss department are from implantable-grade titanium, which is strong and light, but also tends to be very unforgiving and tough to machine. And, of course, some parts present more challenges than others. According to Mr. Selvia, the most challenging parts are the pedicle screws.
“They’re a double-lead thread,” he says. “We have to whirl that thread, which requires a double-lead insert and is kind of tricky to make just right to produce the thread you need.” But the more remarkable part of the process, which Amendia recently adjusted, is broaching the hex form.
Originally, the parts were being produced with a full-form broach made from cobalt steel, which generated about 300 to 400 parts per tool. The process was not every predictable. The tool life was fair, but the unpredictable way the tools would break down was not very favorable. Mr. Selvia felt sure a better method was available.
About 3 months ago, Horn USA Application/Sales Engineer Michael Morgan was in the shop discussing tooling options in some other processes. Mr. Selvia happened to notice the N105 carbide broaching tool in the Horn catalog. “It was exactly what I thought we needed to make the hex,” he says.
This tool is not a full form, but rather a 60-degree form that pecks at the workpiece and creates the form one side at a time. The gradual forming process enables it to be more controllable, and the material is, therefore, more forgiving on the tool. “I’m now getting about 10 times the tool life from a tool that costs half as much as what we used before,” Mr. Selvia says.
Broaching a Hex
Mr. Selvia says the new broaching tool works better for Amedia because the entire tool form is not forcing itself into the titanium at one time. Instead, only a piece of the tool goes in and scrapes a small amount of material away with each pass.
“Imagine a shaper tool,” he says. “As it creates a hex hole, it’s only touching two of the six sides at a time. It removes material at about a thousandth at a time down to the right size, and then indexes 60 degrees. It pecks away at the material without too much pressure on six sides of the tool.”
Because only two sides of the hex are machined at a time, the process is considerably slower. But Amendia performs the broaching operation on the subspindle while the other machining takes place on the main spindle. Running simultaneously, the broaching is completed first anyway.
“This process doesn’t cost us any time,” Mr. Selvia says. “And it saves us money and increases our throughput.” The improved performance and longer tool life have enabled Amendia to run unattended through the night with more confidence, which has further increased the production capabilities. “With the previous process, the tool would break unpredictably,” Mr. Selvia says. “That’s no longer the case.”
The icing on the cake is that the quality of the finished parts seems to be better, as well. The improved surface finish can be partly attributed to more efficient and effective chip removal. With the full-form, six-sided tool, a large chip would be pushed down to the bottom of the hole and then often would need to be dug out with a drill.
The broaching process, by pecking away only a thousandth at a time with each pass, creates very small, fine chips that clear away without complication. Also, according to Mr. Morgan, the Horn broaching tools are sharper than a wobble broach or rotary broach, and by shaving the material away rather than pushing it, a smoother, shinier finish can be achieved.
The broaching system has led to other improvements in the process for Amendia, as well. Because only one corner of the hex shape is being cut at a time, the process has more adjustability. If the machine is misaligned, for instance, or if the hex is undersized, additional taper can be added or an additional pass can be added to the program. With rotary broaching, the operator has only one shot at getting it right. If the form is not right, the part is scrap.
Amendia has also realized significant savings in setup time. The broaching tools can utilize the same toolholder as any Horn USA boring bars or face grooving tools or any others from the 105 Series. The operator simply replaces one insert for another one, without any need for
Although it’s a completely different approach with a different tool, the process has fit in well at Amendia. “Everything about it has been an advantage over the old method—cost, speed and finish,” Mr. Selvia says. “We’re very pleased with it.”
With plenty of experience, he feels that learning how to best use the tool was pretty straightforward. He wrote a macro program to peck the hex out to the right size based on the variables that applied to each screw design.
“Just drill the hole to the right size and use the tool in a common sense way,” he says. “Anyone with some experience with CNC Swiss wouldn’t have a problem with it. It didn’t take us long at all to get it incorporated into our system.”
Amendia is regularly broaching on three of its Nexturn machines for anything with a hex in it. Currently that includes pedicle screws, cervical screws and set screws. The company also uses the Horn broaching tools for Torx work on a variety of cervical screws.
The hex and Torx tools bring the same advantages, but simply use a different form. With Torx, material removal is done one lobe at a time, as opposed to the hex doing one corner at a time. A common method for the Torx form is milling using a very small-diameter mill. While effective, this method can be time consuming because the small diameter end mill requires close attention all the way around the periphery of the form.
Overall, the company’s relationship with Horn has developed nicely, and Mr. Selvia is considering moving to Horn tooling for some other jobs as well. “We’re happy with the way Horn USA operates,” he says.
“Michael (Morgan) is knowledgeable and very available when we need him. Their network is very responsive and easy to work with. They don’t hesitate to adjust their stock if we need them to.”
And who can argue with a tool life increase of 10 times? Besides the obvious savings in tooling costs, it also carries over to better production rates, reducing the frequency of machines being stopped for tool breakage. With fewer broken tools that go unnoticed, scrap has been reduced, as well. And the door has been opened for successful lights-out machining.
So the results speak for themselves—a simple change in tooling has had a big impact on production savings.
We have had several inquiries regarding steep taper rotary toolholders specifications. Below you will find all of the technical reference information related to V-Flange Tolling Tapers and dimensions.
CAT V Flange Taper Specifications
About the ASME B5.50 – 2009 Standard
This Standard pertains to the standardization of a basic tool holder shank and retention knob for computer numerically-controlled machining centers with automatic tool changers. The requirements are intended to provide tool holder interchangeability between machining centers with automatic tool changers of various types.
The dimensions for cone-angle control are in accordance with the International Standard ISO-1947. This Standard will improve the understanding of the “CAT” toolholder, its associated components, and nominal operational values. It unifies the principle components of the basic machine tool holder interface—toolholders hank and spindle receiver geometry, pull stud, and conical taper information--into a single-source reference, providing instant access to information.
This new information also eliminates ambiguities and establishes absolutes for all aspects of the toolholder/spindle interface.Intended forthose involved in the design, manufacture, use, or maintenance of steep-taper (7:24) toolholders and their ancillary components.
BT Taper Specificationsƒ
BT-40 Shank is also known as: JMTBA MAS-403 "BT", JIS B 6339 - 1986, JIS B6339 - 1992, and ISO 7388/1 - 1983.
The spindle interface JIS B 6339 as the traditional interface for milling spindles distinguishes itself through it robust design. Its field of application ranges from fine machining to heavy duty roughing. The tool holder is pulled in the milling spindle with the help of an additional pull stud.
The centering takes place via the taper contact. Therefore, the JIS B 6339 interface is primarily suitable for applications with a spindle speed of up to 12,000 rpm in an unbalanced condition.
CASE STUDY: EZ Burr visits GM Romulus deburring internal ribs in a very long engine block.
The speed & feed is 1250 RPM @ 400 mm/min.; cycle time 12-15 seconds.
EZ Burr had to make an extra length tool that could handle these cutting conditions without adding any cycle time to the process. The insert had to produce a clean, smooth surface and run a consistent number of blocks each and every shift.
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