Fullerton Tool Co. (Saginaw, Michigan), a manufacturer of solid carbide cutting tools, has hired Justin Verburg as National Sales Manager. In this position, Mr. Verburg will be overseeing the company’s direct regional sales managers and outside sales rep agencies.
Mr. Verburg joined Fullerton’s sales team in early October 2017 and is based out of Fullerton’s headquarters in Saginaw. He has experience in both the manufacturing and cutting tool industries and has held a diverse range of roles including product management, general manager, and director of sales and marketing.
“Justin brings a well-rounded, family-oriented perspective to WCMT Insert Fullerton Tool,” says Mat Machining Inserts Curry, Vice President of Sales and Marketing. “Justin’s passion and experience will provide valuable insight to Fullerton and will help guide our sales team to provide the best total solutions to our customers.”
The Carbide Inserts Website: https://www.estoolcarbide.com/machining-inserts/
Imagine the sound of a 55-gallon drum filling to the brim in minutes flat with a steady stream of coins dropped unceremoniously from high above. That is how Anthony Fettig, CEO of machine tool builder Unisig, described what it’s like to witness the company’s largest, most powerful deep-hole-drilling machines in action during a recent press event.
With more than 300 horsepower behind the tool, holes can be drilled to extreme diameters and depths (20 inches and 32 feet, respectively) in even the most difficult-to-machine materials, including Inconel and other nickel-based alloys. Automatic toolchangers can accommodate shanks as long as 24 inches on some models, and the machines’ beds can be large enough to require shipping in separate sections, each measuring as long as 25 feet, for precision assembly later.
Unisig’s line of deep-hole-drilling machines is not limited to these behemoths. On the other end of the spectrum are machines designed for holes measuring less than 1-inch deep and no broader than 0.04 inch in diameter.
The most important consideration in drilling, Mr. Fettig says, isn’t necessarily the depth or the diameter of the hole: It’s more about the ratio between the two. “We perk up and get happy,” Mr. Fettig says about being presented with depth-to-diameter ratios ranging to 300:1. “We know we can take (customers’) problems away.”
While the company is known for deep-hole drilling, the term itself does not do justice to the breadth of these machines’ capabilities, nor to the breadth of the company’s engineering expertise. With the typical application defined by more than just challenging hole-making operations, he believes “deep-hole machining” is a better descriptor.
In an era when manufacturers of all stripes seek to consolidate operations on fewer pieces of equipment, Unisig has taken the position that a gundrill does not have to be just a gundrill. Indeed, much of the builder’s equipment demonstrates a focus on external workpiece features as well as internal ones.
Although stock delivery machines are available, a significant proportion of Unisig machines are made to order from modular platforms. One example of such a platform is the USC-M line, which combines powerful hole-making with all the general machining capability of a five-axis mill. This machine is particularly useful for plastic-injection moldmakers that annot afford spending too much time drilling deep water-cooling lines. Unisig machines are designed to perform these operations in the same setup as the complex contouring required for exterior features, Mr. Fettig says. Although the machines trend large, workpieces don’t have to be, he continues, explaining that table rigidity and overall volumetric precision eliminate the need to ensure that smaller workpieces (or features of those large enough to overhang the table) are located in a specific “sweet spot.”
Five-axis capability is a function of this rotary table as well as a dedicated, 50-taper, tilting milling spindle mounted parallel to the machine’s drilling spindle. Machining is said to be just as precise—that is, volumetric accuracy is the same—regardless of the tilting spindle’s angle and position within the workzone. “Performance and accuracy aren’t compromised in seemingly less rigid headstock positions,” he says. “Compound angles are effortless.”
He attributes this precision to scale feedback and finely tuned, high-performance servo drives that facilitate precise interpolation. He also credits the company’s strategy of building machines “from the ground up” at the Milwaukee factory. Even CNC engineering is performed in house, including the defining of kinematics and other associated tasks, with components sourced directly from such manufacturers as Siemens, Heidenhain and FANUC.
Other platforms are similarly configured for work ranging from oil and gas components to aircraft landing gear and various hydraulic systems. Each machine is made to order, with automation systems in particular differing widely from customer to customer. Beyond robot-tending and mulit-machine cells of multi-spindle drilling machines, automation systems range from pallet changers to complex conveyors, roller steadies and other systems involving in-process gaging and even extra servo-driven axes of motion dedicated to streamlining setup and unloading alike.
Mr. Fettig emphasizes that the reason why “deep-hole drilling” is inadequate to describe what Unisig does has as much to do with what goes on inside a hole as what goes on outside of it. Beyond basic drilling, reaming, tapping and so forth, potential operations include counterboring, slotting and trepanning. Profiling is common as well, including stepped diameters, precisely curved internal radii, sculpted contours and requirements for specific levels of surface finish.
When it comes to this kind of internal machining, cutting tools literally take the initiative. “The majority of deep-hole tools and processes are based around the idea of the tool guiding itself close to the cutting edge,” he says. Standard deep-hole drilling tools come in two basic varieties: gundrills and Boring and Trepanning Association (BTA) drills.
The tools most commonly associated with extreme length-to-diameter ratios, gundrills are available with single-effective geometry. This means the cutting action is all on one side, a contrast with the double-effective geometry that characterizes most conventional drills. This construction provides the necessary clearance for chips and coolant. Typically, wear pads on the periphery help keep the tool in place and provide a burnishing action that smooths the workpiece surface. Point angle and location influence cutting thrust and radial force on the tool at a given set of parameters. The most precise hole making is achieved when tool and workpiece rotate together, he adds, and rotating the workpiece by itself typically produces better results than rotating the tool by itself.
Solid-carbide gundrills are particularly rigid. These tools offer the advantage of resharpening, but they are effective only at diameters smaller than about 300 mm. After that point, they tend to become expensive and/or and fragile, Mr. Fettig says. For larger diameters, tools are available with steel shanks and brazed carbide tips, with “V” notches rolled into the steel for chip evacuation. Alternatively, indexable-insert models eliminate the need to discard the entire tool when worn. That said, these Carbide Threading Inserts models might not be as precise as brazed-tip tools because each insert-tool connection is subject to variance.
Whereas a gundrill is designed for internal coolant delivery and external chip exhaust, BTA drilling routines involve evacuating chips and coolant through the center of the tool itself, in the opposite direction of the feed. As a result, holes should be at least a certain size—about ½ inch—before considering this tooling, Mr. Fettig says. As is the case with gundrills, BTA tools are available with both brazed and indexable cutting edges. These tools also come in spade-tip geometries, which Mr. Fettig says are particularly useful for cross-holes (such as those typical of the water-cooling lines in the aforementioned moldmaking applications). Although he emphasizes that the gap is closing, BTA drills generally offer higher feed rates, greater rigidity turning inserts for aluminum and improved chip control.
Beyond these basic tool types, many applications involve custom form tools for imparting more complex profiles. Generalities are difficult to draw about these widely varied offerings; suffice it to say that even familiar-looking geometries require manufacturing for a specific size bore, at the least. For example, bottle-boring tools use CNC-actuated axes to drive cutting edges away from and back into the shank as needed to create internal profiles. Without precise sizing, such action would be impossible. “Given that these tools have to guide themselves, careful planning is critical,” Mr. Fettig says. The same could be said of applications that require integrating that hole-making process with complex outside machining as well.
When a shop runs at full capacity, it must make efficiency gains any way possible. A few years ago, one such shop, Kennebec Tool & Die, embarked on a lean manufacturing program to eliminate waste and improve productivity. With 70 employees working in three shifts around the clock seven days a week, the Augusta, Maine-based company needed to standardize processes, equipment and tools in order to streamline its operations. One of the changes the shop made in order to meet its goals was to invest in a machining center equipped with through-spindle coolant.
However, the shop faced a persistent problem in its attempts to use the new machine and corresponding tooling for an important job—producing 700 assemblies per year for the semi-conductor industry. The shop was still on a learning curve for the new machine and tools, and cycle time issues on a particularly problematic component of the seven-part assembly reduced productivity.
Made of 17-4 heat-treated stainless steel, the raw stock for the component arrives as a 4-inch-diameter bar that is cut to a rough length of 8.5 inches. After rough and finish turning, the component requires drilling of a 5-inch-deep internal bore with a tight tolerance. "Our turning operations were running pretty standard; it was really the drilling that was taking a long time," says Harvey Smith, vice president of operations.
Paul Owen, tooling room supervisor, says the source of the drilling operation’s lengthy cycle time could be traced to problems with consistent tool life. "Chips were wrapping around the drill, destroying the tool and/or scrapping the part," he explains. "We might get five parts from one insert and then six or eight from another."
Kennebec tried to work through the problem, but had to slow down the entire process in order to clean out the chips, further impacting productivity. The shop knew it needed to upgrade its drilling tools. However, in keeping with its lean manufacturing program, it sought to do so with the goal of not only addressing this specific application, but also reducing its total number of drill styles by finding a product that would work in a variety of situations. Soon, it had narrowed the vendors down to Seco Tools (Troy, Michigan) and a competitor.
To make a decision, Mr. Smith issued a challenge to Seco technical specialist Bryan Daniels: "If you can make this particular operation work, then I’m changing over to Seco."
Mr. Daniels delivered. He suggested a 1.187-inch-diameter, 5×D Perfomax indexable drill for the troublesome assembly component application. The Perfomax drill features two coolant holes and large chip flutes with a flute angle that is said to promote efficient coolant flow and effective removal of coolant and chips. This flute and the tool’s coated body and inserts are designed to allow high feeds and speeds while avoiding deflection, poor tool life and quality, even with long lengths and deep-hole drilling applications. Unlike many other indexable drills, the Perfomax can use two different insert grades. A tougher grade is located in the inboard position, while a more wear-resistant grade is mounted in the periphery pocket. Inserts are square to provide a strong 90-degree corner and the economy of four cutting edges.
RCGT Insert"The operation was pretty much nailed as soon as we tried it," Mr. Owen says. "Bryan suggested the feeds and speeds, and we had no problems. He worked with us and optimized the parameters until we got a good average of parts per insert."
The drill ended up producing about 20 parts per edge—a threefold improvement in tool life compared with the shop’s previous drill. Additionally, the tool reduced cycle time from 1.21 to 0.53 seconds. While this might not seem significant, Mr. Smith explains that the actual cycle time savings are greater than the numbers show because the shop previously changed tools every five to eight parts. The drill’s longer tool life provided cost benefits, as well. While the Seco inserts cost more than competitive inserts, the increased tool life achieved with Perfomax actually reduced WCMT Insert the comparative cost by $1.05 per produced part, Mr. Smith says.
Now, Kennebec uses Perfomax for almost all of its standard drilling applications. In fact, the drill has worked well enough to prompt the company to give Mr. Daniels a chance to prove Seco’s worth in other areas, including an 8,000-part aerospace order that requires a combination of turning and milling operations. "After (Mr. Daniels’) dedication on this last process and the success we achieved, we will certainly at least give Seco a try," Mr. Smith says.
The Carbide Inserts Website: https://www.estoolcarbide.com/product/togt-deep-drilling-inserts-cnc-lathe-cutting-indexable-carbide-drill-insert-p-1207/
It seems that in many corners of the metalworking world one sees trends away from the specialized and toward the more generalized. In automotive manufacturing, for example, the big, dedicated, transfer-lines are giving way in many applications to flexible, modular units that can be effectively used for families of similar parts and then re-used for a whole new family of components.
Then there’s the idea of machines that turn/mill or, depending on your perspective, mill/turn, which is helping general metalworking job shops and production shops to complete in one setup what took many operations across different tools to machine. And of course there’Cutting Insertss the machining center, which combines several independent machining operations such as milling, drilling and tapping into a single, one-stop processing center.
Likewise in the cut itself, where the work of metalcutting actually gets done, there have been advances in multiple operation capability from cutting tool builders as well. An example of this is the grooving cutter for turning.
In this article we’ll look at how the application scope for these cutters has expanded beyond just grooving and cut-off. We’ll also look at the milling cutter equivalent—slotting tools—and discuss how these tools are being applied in new and different ways.
To find out what these tools can and cannot do, we talked to Horn, USA (Franklin, Tennessee) about how to use grooving and slotting tools in turning inserts for aluminum applications that fall outside of what has been their traditional niches.
The advent of the indexable insert grooving-tool has delivered huge benefits to shops that use them. Advances in carbide pressing technology allow chip breakers and various geometric configurations to be imparted onto even very small width cutters.
The payoff for shops has been better quality both in size and surface finish, not to mention significant increases in cutting speeds resulting in faster cycle times.
During virtually any plunge feed grooving operation, tremendous cutting forces in the form of heat and stress are generated at the tip of the insert. Insert design goals are directed to overcoming these factors. Increased tool life, accurate dimensional repeatability and better surface quality are the results.
The relative contact area between the grooving tool and the workpiece is very narrow. Grooves down to 0.010 inch can be cut with indexable insert tools. Grooves can also be large. In some applications, groove widths of 1.75 inches are plunge cut using an insert with the same width.
Regardless of the groove width, all plunge-grooving operations basically operate in the same way. A Z-axis feed creates axial forces that are directed into the insert edge. The edge is supported (Horn’s holder supports 80 percent of the insert’s length) by the tool holder body which, in turn, is held in the turning center tool turret. Ultimately, the forces, which on plunge cuts are pretty much straight-line, get channeled into the machine tool base.
There are many standard and special insert sizes, shapes, coatings and substrate combinations available for grooving. Cutting toolmakers have covered plunge grooving well.
However, many shops are extending the use of grooving cutters by performing some turning operations, which is side cutting, with the grooving insert. Moving from a single axis plunge feed to an X-Z axis combination is where shops really see some production gains by extending the versatility of grooving inserts. But there are some process considerations to examine before ripping a contour or turning a face with a grooving tool.
Unlike plunge grooving, which works to the mechanical strength of the insert and holder, turning along the workpiece axis has the opposite affect. Turning exerts radial or side forces on the insert and holder that are trying to bend or deflect the tool. The relatively thin cross section of the grooving tool provides little mass to offset this tendency toward deflection.
Horn and other grooving toolmakers have designed inserts and holders that allow for the deflection from turning without a loss of precision or performance. This is done in several ways.
On combination grooving and turning inserts, geometry is designed and then pressed into the blank creating free cutting in both axial and radial directions. Relief angles on the side of the insert allow chip clearance during side cutting operations. Free cutting geometry reduces cutting forces. Reduced cutting forces reduce deflection.
In most applications where these inserts are applied, the job requires cutting between shoulders. Usually when the distance between shoulders is too large for a single grooving insert to be plunged, turning passes between the shoulders are necessary. Side turning also produces better surface finishes on the sides and bottom of the cut than plunge cutting.
In these cases, Horn recommends a minimum grooving insert width between 0.098 and 0.400 inches. Wider is better for side cutting with a grooving insert. And even with a stiff tool setup, there are some programming considerations for side cutting as well (see box).
By its nature, the grooving insert is a tricky shape to grab. This is especially true in smaller widths. It’s long and narrow because the cutter is used to plunge deep between relatively narrow shoulders. This shape, unlike a triangle, square or round insert, doesn’t provide a large surface area on which to clamp.
Even in plunge cuts, forces are trying to twist the insert out of its seat in the tool holder. Side cutting puts even more demand on the tool holder’s ability to hang on to the insert.
To help overcome the side cutting forces, Horn presses a prism shape in the top and bottom longitudinal axes of the insert. This prism fits a corresponding slot in the toolholder clamp. An insert, without some sort interlock shape between it and the holder, will tend to shift or possibly loosen under cutting conditions.
Under clamp pressure, the prism and its receiver on the tool holder secure the insert top and bottom over the full length. This clamping system helps the insert resist deflection from side cutting forces while at the same time maintaining a rigid connection between the insert, holder and machine turret. A rigid connection between the tool holder and insert is a critical consideration for shops that want to side cut with grooving inserts.
Milling operations too can take advantage of multiple operations using one cutter. An example is the slot-milling cutter. Usually its specialty includes cutting keyways and T-slots. Generally cutting a slot or key involves feeding the X or Y axis while the Z axis is fixed at the programmed depth.
With the advent of circular and helical interpolation on machining centers, the versatility of these typically dedicated cutters has been expanded. Horn and other cutter makers produce indexable insert cutters that can face mill, clean up a bore, scribe a thread, groove, or step inside the bore, all with a single tool. But without interpolation, these operations would require dedicated cutters to perform them.
An impetus for shops to get more operations from a given cutting tool is the relatively small tool capacity of most turning center turrets. The ability to load a sufficient number of tools for more than a couple of jobs is often restricted by turret capacity. This extends setup time from job to job.
If a shop can use a grooving tool for two or more operations that would traditionally take individual cutters, it saves those valuable tool pockets for other tools or redundant tools. This extends to the tool room as well, with less insert and cutting tool inventory to stock and maintain.
Using grooving tools for side turning is not suggested as a replacement for general purpose turning tools. Likewise, slot-milling cutters cannot perform face milling and boring as well as tools specifically designed for these functions.
However, in an application where turning between shoulders and facing operations or, ID boring with internal grooves are called for, using one tool for several is a good option. In a milling application, the ability to face a surface then interpolate a bore and cut a spiral groove or O-ring slot with one cutter saves cycle time.
The idea behind using one tool for more than one operation is to help shops save cycle time and reduce complexity in some of their processes. Advances in insert pressing and grinding technology along with better substrates and coatings allow inserts to be used in innovative ways. And, when combined with the versatility of the modern CNC machine tool, the cutting tool and machine applied together can help get the job done better, cheaper and faster.
The Carbide Inserts Website: https://www.estoolcarbide.com/coated-inserts/dnmg-insert/
Iscar’s Dove IQ Grip tooling system Deep Hole Drilling Inserts features a locking mechanism to accommodate wide inserts measuring 10, 12 and 14 mm, and mounted on a 53-mm blade. The tools consist of turning inserts for aluminum blade-carrying cartridges attached by a rigid dovetail connection. The system is designed so that the cartridge absorbs damage in case of a crash during machining. According to the company, this capability, combined with the cartridge system’s compatibility with specials and exchangeable heads, provides savings on tool cost.
Iscar says the system’s frontal locking mechanism needs only a half-turn to lock the insert and its lack of an upper clamp or jaw promotes unobstructed chip flow. Additionally, there is no risk of falling parts because there is no need to fully extract the screw. A bottom frontal coolant K-type system (high pressure possible), is said to prolong tool life and improve chip formation, especially in deep, wide and heavy grooving operations.
The Carbide Inserts Website: https://www.estoolcarbide.com/coated-inserts/dcmt-insert/
