Conditioning of the cutting edge, such as a honing or chamfering, to make it stronger and less susceptible to chipping. A chamfer is a bevel on the tool’s cutting edge; the angle is measured from the cutting face downward and generally varies from 25° to 45°. Honing is the process of rounding or blunting the cutting edge with abrasives, either manually or mechanically.

The H-Carb Seven Flute High Efficiency Endmill specializes in deep axial trochoidal and high-speed machining applications. Offered at various lengths of cut, the 7 flute design creates a superior finish to conventional 5 or 6 flute tools.

Cooling lubricants and cutting fluids can dramatically affect the reliability of grooving and parting-off processes. When applied correctly, cooling lubricants can reduce the temperature of the material being machined and improve chip removal. Keep in mind that no matter how much coolant is poured on an application, or how effective the coolant is, it will have little to no effect if it is not applied to the cutting edge.

Coolant supplied below the cutting edge will reduce the cutting zone temperature while minimizing flank wear. This also aids in chip removal. Reducing the temperature makes it possible to use tougher varieties of inserts while maintaining tool life and cutting parameters or, in some cases, increasing tool life and improving process reliability. This process also delivers the best results when engagement times are long and temperature is a limiting factor.

Editor’s Note: This article was developed from information presented during the Horn Technology Days 2017 event held at Paul Horn GmbH in Tübingen, Germany, May 10-12.

Turning application technology has come a long way from the time when you simply clamped a piece of tool steel in place for a turning application. Today the flexibility, simplicity, increased stability or rigidity, and improved accuracy are making modular grooving systems popular.

Hardness is a measure of the resistance of a material to surface indentation or abrasion. There is no absolute scale for hardness. In order to express hardness quantitatively, each type of test has its own scale, which defines hardness. Indentation hardness obtained through static methods is measured by Brinell, Rockwell, Vickers and Knoop tests. Hardness without indentation is measured by a dynamic method, known as the Scleroscope test.

We can’t talk about coolant delivery without talking about coolant pressure. With the right coolant pressure it is possible to influence chip formation in grooving and parting off. Coolant pressure as low as 5 bar (72 PSI) can start to reduce crater wear. As the pressure increases to 20 bar (290 PSI), it can reduce BUE. Coolant pressure of 40 bar (580 PSI) can influence chip control and direction. High pressure application of 80 bar (1,160 PSI) or more can aide in chipbreaking.

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Available tooling that can be marked as First Choice includes the 525-ball nose end mill (0.2 mm to 6.0 mm) and 570 bull nose copying end mill (0.4 mm to 6.0 mm) mold construction tools for HSC operation in steel material hardness’ from 52 to 65 HRC. They feature state-of-the-art cutting-edge geometries, stable release mechanisms with a balancing effect, defined edge preparation and optimized microgeometry ensure top performance, maximum precision and process reliability. Smooth, high-performance coatings such as VaroCon (525) or NanoCon (570) support rapid chip clearance.

With its First Choice Inovatools designations, the tooling specialist offers users the opportunity to identify tailor-made tools for a company’s specific cutting requirements. One example is machining stainless steel. First Choice can identify top tools in the Inovatools online shop or in its main catalog, including for tool and mold construction.

So what about cam machines that are 20 or 30 years old or older? Truth is, many companies still run older cam-style machines, and these machines aren’t being ignored. There are new options for them too.

Coolant applied through the toolholder is precisely directed to the cutting edge, where it will have the most impact on the cutting process.

Another search function is the InoCut cutting data program. The program allows users to search for tools by the application and specified cutting values. In the complete catalog, the tools are marked as ‘First Choice’ accordingly.

The curve segment milling technology also opens up production options. For example, undercuts, freeform surfaces and variable setting angles can be reliably created. In addition, complex contours can be pre-finished and finished, even on narrow inside radii.

Inovatools has copying and ball nose end mills featuring the Dia-Dur coating in its range for machining graphite electrodes. The excellent adhesion properties of CVD high-performance Dia-Dur coating gives the Diamond edition tools similarly good physical and chemical properties to that of natural diamond. The tools feature extreme hardness and smoothness, high chemical resistance, excellent thermal conductivity and abrasion resistance.

Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.

Coolant can be supplied by an external or internal means. When external coolant is supplied via nozzles spraying on the toolholders, only a small amount of the coolant actually gets to the cutting edge so it has less of an effect on the cutting application than coolant delivered using a through-coolant toolholder delivery system. This is especially true when machining deep grooves and working with materials that are easily work-hardened, such as superalloys and stainless steels.

The CurveMax has a special geometry that permits bigger path distances and line jumps during pre-finishing and finishing. Although the working radius is larger than that of a traditional full-radius mill, the tool still has the same diameter, which leads to a reduction in process times. The larger engagement width means the cutting edge does not suffer from wear at any point. Combined with the extremely smooth, high-performance VaroCon coating, this helps to increase the tool’s service life. The larger and flatter overlap reduces roughness and ensures surface finishes even better than those created by traditional full-radius mills. Inovatools offers the CSC-CurveMax mills in conical and tangential form as four-edged cutters for finishing in different sizes and radii.

Chip control ensures that chips will not cause problems during the machining process. The goal is to produce short helical, spiral, comma, or tear chips (shaped like 6s and 9s). These types of chips are more likely to provide stability in the grooving and parting-off process.

The pre-plumbed systems simply bolt on to accommodate many coolant delivery options that offer quick changeover without the need to hook up coolant lines. Many of the modular systems also allow for center height adjustability that can be especially helpful when cutting difficult materials. A large number of combinations are possible with a relatively small number of components, which enables standard tool systems to be used throughout an entire production process regardless of the machine interface.

The solid carbide curve segment cutting (CSC) mills in the CurveMax series are an example of Inovatools tool technology with adapted process technology for copy milling. In tool and mold construction, the solid carbide curve segment mills in tangential and conical form shorten the process times required for finishing complex, freeform surfaces in a wide variety of materials.

Space provided behind a tool’s land or relief to prevent rubbing and subsequent premature deterioration of the tool. See land; relief.

Grooving and parting-off applications present unique challenges. Unlike a longitudinal turning application that allows chips to move in three directions without restrictions, during grooving and parting-off processes you are machining between flanks, which confine chip movement to just two directions.

According to Kline, “HSC machining of graphite electrodes, for example, using diamond-coated tools is the method of choice in tool and mold construction. Only using high-quality, robust tools can cutters comply with narrow tolerance zones while milling materials quickly and cost-effectively.”

Steel containing specified quantities of alloying elements (other than carbon and the commonly accepted amounts of manganese, sulfur and phosphorus) added to cause changes in the metal’s mechanical and/or physical properties. Principal alloying elements are nickel, chromium, molybdenum and silicon. Some grades of alloy steels contain one or more of these elements: vanadium, boron, lead and copper.

Through-coolant holders eliminate the need to adjust coolant lines and always direct the coolant to the tool’s cutting edge. External coolant lines can be bumped out of alignment while operators are changing tools or loading parts, which can cause process variation or premature tool failure.

Materials are changing, and they are generally not getting easier to machine. Challenging materials such as heat-resistant superalloys, stainless steels, and lead-free alloys such as brass pose new challenges that demand modern machining strategies.

Substance used for grinding, honing, lapping, superfinishing and polishing. Examples include garnet, emery, corundum, silicon carbide, cubic boron nitride and diamond in various grit sizes.

With the Diamond edition, Inovatools highlights its comprehensive expertise in this area. For example, the end mills (tolerance H5) with radius tolerances of ±0.003 mm are ground with extreme precision, and the concentricity of the full and corner radius end mills is 0.005 mm. Selected carbide grades are essential to ensure consistently high quality.

Runs endmills and arbor-mounted milling cutters. Features include a head with a spindle that drives the cutters; a column, knee and table that provide motion in the three Cartesian axes; and a base that supports the components and houses the cutting-fluid pump and reservoir. The work is mounted on the table and fed into the rotating cutter or endmill to accomplish the milling steps; vertical milling machines also feed endmills into the work by means of a spindle-mounted quill. Models range from small manual machines to big bed-type and duplex mills. All take one of three basic forms: vertical, horizontal or convertible horizontal/vertical. Vertical machines may be knee-type (the table is mounted on a knee that can be elevated) or bed-type (the table is securely supported and only moves horizontally). In general, horizontal machines are bigger and more powerful, while vertical machines are lighter but more versatile and easier to set up and operate.

The P-style blades have many options with indexable blades that are designed to fit in existing tool blocks. Solid-carbide options allow for direct replacement of these blades for groove and cutoff applications.

Coolant from above can greatly improve chip control, which is a key to longer tool life. It can also reduce built-up edges (BUE).

High-temperature (1,000° C or higher), atmosphere-controlled process in which a chemical reaction is induced for the purpose of depositing a coating 2µm to 12µm thick on a tool’s surface. See coated tools; PVD, physical vapor deposition.

“Our special range of mill products is designed for the most varied of applications in this machining segment,” said Douglas Kline, managing director of Inovatools USA LLC. “The tools have been adapted for the relevant applications and materials in terms of substrate, geometry, chip control and coating.”

The tools include universal, roughing, finishing and special mill series’ such as mini-shank, copying and full-radius end mills in an array of designs and dimensions and featuring application-optimized high-performance coatings.

Consider two key points to avoid problems. One is chip forming and the other is chip control. Good chip forming ensures that the material is plastically deformed by the tooling so the chips are narrower than the width of the cutting insert to avoid damage to the groove flanks. An example is a 5-mm-wide groove insert that creates a chip that is 4.85 mm wide.

In tool and mold construction, highly abrasive graphite materials and extremely hard materials such as alloy steels of up to 65 HRC or more are dominating the industry. The cost-effective creation of 3D contours and shaped elements impose demanding requirements on the mills and on process management.

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Let’s use a lead-free brass alloy as an example of a challenging material. Brass is known for its good machinability properties. A leaded, free-machining brass is particularly popular in the production of turned parts. Tools used to machine free-machining brass have a negative chipping angle that produces small, short chips. With new laws that regulate the use of hazardous materials such as lead, new grades of lead-free brass have emerged that require a change in machining processes.

Keep up to date with the latest news, events, and technology for all things metal from our pair of monthly magazines written specifically for Canadian manufacturers!

It is important to consider the economics of parting off. Since parting off is often the final operation in manufacturing a component, reliability is crucial.

New modular tools make it possible to produce assemblies that are tailored for specific applications while being made up of completely standard components. This can reduce the need for special tools. These systems provide a stable structure, while their modular design gives you flexibility and a large variety of tool configuration options.

When internal coolant is supplied directly through the toolholder, it is directed precisely to the cutting edge, enabling a much more reliable process. Internal coolant, or through-coolant, holders are available in many variations. Some direct the coolant to immediately above the insert, some to immediately below.

For steel processing, Inovatools offers the FightMax and FightMax INOX mill series (for stainless steels). With a high-performance coating that provides a high resistance to heat, FightMax mills can withstand high levels of tool wear over very long periods, even at high feed rates and cutting speeds.

The narrowest indexable inserts should be used in the parting-off process as this can factor into significant material cost savings. These savings multiply exponentially when you are machining alloys that have a substantially higher material cost, such as high-temp superalloys.

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The negative chip angle that works so well in free-machining brass does not work nearly the same in the lead-free version. Machining trials have shown that lead-free brass is best machined with geometries more suited for steel. For the best process capability it is important to apply the correct geometries and grades for the material you are machining. Not all brass is the same.

Inovatools USA LLC, a Germany-based company with U.S. offices in Hartland, Michigan, offers a broad product range of high-performance solid carbide mills that meet the exacting requirements in mold, fixture and die manufacturing.