Frequently Asked Questions
    Milling in General
  • What is a cutting edge angle and what is a lead angle?
    There are various international and national standards that specify the active geometry of cutting tools very precisely. The “cutting edge angle” is the angle between the main cutting edge of a milling cutter and the plane containing the direction of feed motion. "Lead angle" (or “approach angle”) is the angle complementary to the cutting edge angle, i.e. the sum of these both angles is 90°. For example, for a typical face milling cutter the cutting angle is the angle between the cutting edge and the plane, which the cutter generates. If this angle is 60°, then the lead angle will be 30°. The cutting edge angle and the lead angle are equal only for 45° milling cutters. The term "lead angle" is more commonly employed in the U.S., while "approach angle" is often used in Europe.
  • What is the difference between "face mill" and "shell mill"?
    These two terms relate to different and complementary features of milling cutters. They are not interchangeable. Milling cutters are classified according to the following main factors:
    • Machine surface type: plane, shoulder, 3D-surface, etc.
    • Cutter mounting method: on mandrel or arbor, in holder, directly in spindle
    • Structure: monolithic; assembled
    • Cutting part material: high speed steel, tungsten carbide, ceramics, etc.)
    "Face mill" characterizes a main field of application - milling flats by the cutting face of a mill. "Shell mill" refers to the design configuration of a mill: the mill has a central bore for mounting on arbor. This configuration is typical for face mills.
  • What is the difference between heavy and heavy-duty milling?
    Sometimes the terms “heavy” and “heavy-duty” are used mistakenly as synonyms. In principle, “heavy milling” (and “heavy machining") relates to milling large-sized and heavy-weight workpieces on powerful machine tools and refers more to the dimensions and mass of a workpiece. “Heavy-duty” specifies a degree of tool loading and mainly characterizes a mode of milling.
  • Which cutting conditions are considered as unfavorable and which are unstable?
    Unfavorable cutting conditions include:
    • workpiece with skin (siliceous or slag, for example)
    • significantly variable machining allowance
    • considerable impact load due to non-uniform machined surface
    • surface with high-abrasive inclusions
    Unstable cutting conditions refer to the low stability of a complete system (machine tool, workpiece holding fixture, cutting tool, workpiece) due to:
    • poor tool and workpiece holding
    • high tool overhang
    • non-rigid machine tools
    • thin-walled workpiece
    The terms "unfavorable" and "unstable" are not interchangeable.
  • How is average chip thickness measured?
    In milling, the thickness of chips is not constant and varies during cutting, depending on several factors. The average chip thickness (hm) is a virtual parameter that characterizes mechanical load on a milling cutter and a machine tool. There are different methods for calculating hm. The most common method is to compute it in relation to the half of an angle of engagement, where the latter is the central angle that corresponds to the arc of a contact between a milling cutter and a workpiece.
  • What is high pressure coolant (HPC) and ultra high pressure coolant (UHPC)?
    There are no strict definitions of high and ultra high pressure coolant (HPC and UHPC correspondingly). Traditionally, machine tools feature coolant supply at pressure 10-15 bar (145-217 psi). This level is now considered as low pressure.
    Various modern machining centers have the option to supply coolant at rates of 70-80 bar (1000-1200 psi), which is considered as high pressure coolant. Ultra high pressure coolant relates to pressure values of 100-200 bar (1450-2900 psi) and even higher.
    Some producers of CNC machine tool equipment manufacture what are known as “medium pressure” pumps; these have values of up to 50 bar (725 psi).
  • What are the benefits of milling with high pressure coolant (HPC)?
    Heat generation is a permanent feature of machining, particularly, milling. If heat generation is intensive, the conventional low pressure coolant forms a vapor layer on the surfaces of a tool and a workpiece. This layer acts as heat sealing, producing an insulating barrier and making heat transfer harder, which significantly shortens tool life.
    Pinpointed high pressure coolant penetrates the barrier and helps to overcome the problem. HPC chills chips quickly, making them hard and brittle. The chips become thinner and smaller, and they break away from the workpiece more easily. High-velocity coolant flow removes the chips. This significantly improves chip evacuation and prevents chip re-cutting.
    HPC improves tool life of a cutting edge due to reducing oxidation and adhesion wear and increasing crack strength. HPC improves chip evacuation because the chips diminish in size, and the high-velocity coolant flow takes them away easily. It allows the design of cutters with smaller chip gullet, leading to a higher number of cutter teeth. Effective cooling reduces the temperature in the cutting zone, ensuring an increased width of cut.
    Overall, HPC provides a good solution for increasing cutting speed and feed rate for boosting productivity.
  • What is the difference between milling with high pressure coolant (HPC) supply through a tool body and turning with HPC?
    In turning, a tool has one cutting edge, while a milling tool features several cutting teeth. The number of coolant outlets in the milling tool is greater. An indexable extended flute cutter, where the teeth are produced by sets of replaceable inserts, will require many more outlets.
    There is a specific relationship between pressure, velocity and flow rate for fluid, e.g. for coolant. In milling, HPC supply through the tool body demands appropriate characteristics of an HPC pump to ensure correct flow volume (flow rate) and not only to meet pressure requirements.
  • Does ISCAR provides indexable cutters for high pressure coolant milling in the standard product line?
    Yes, ISCAR provides these tools in the families of milling cutters for machining titanium and high temperature superalloys (HTSA).
  • Why are nozzles used as coolant outlets in HPC indexable milling cutters?
    There are two reasons for using nozzles as coolant outlets: technological and applicative. HPC supply through the body of a cutter requires small-diameter outlets (as well as demands regarding the shape). As manufacture of the outlets via drilling hard steel tools would encounter technological difficulties, screw-in nozzles represent a more practical option.
    If a depth of cut is smaller than the maximum cutting length of an indexable extended flute milling tool, there is no need to supply coolant to the inserts that are not involved in cutting. To improve performance, you can easy unscrew the appropriate nozzles from their holes, and then close the hole by a plug or a standard set screw.
  • Why are a significant number of HPC milling cutters special (tailor-made)?
    The main consumers of HPC milling cutters are manufacturers working with hard-to-cut materials, for example titanium alloys. In many cases, producing parts from the materials requires a high volume of metal removal. To boost productivity, manufacturers often use unique machine tools, and, to reach maximum operational rigidity, they prefer integral tools with direct adaptation to the spindle of a machine - without intermediate tooling such as arbours or holders. Specific tool diameters, cutting lengths, and overhang, as well as adaptations that vary from one manufacturer to another, demand tailor-made HPC milling cutters.
  • Which families are included in ISCAR’s indexable milling line?
    The indexable milling line consists of cutters intended for the main types of milling operations: milling right shoulders, milling open faces, milling edges (edging) and deep shoulders, milling 3-D surfaces (profile milling), milling slots and grooves, milling chamfers, etc. Separate families of cutters have been developed to handle fast feed milling (a specific machining technique).
  • The logos of various ISCAR’s indexable milling families start with the wording “HELI” (a derivative from “helix”), and phrases such as “helical cutting edge” and “helical milling” are often emphasized as benefits in technical information. Why?
    In the early 1990’s, ISCAR introduced the HELIMILL – a family of milling tools carrying indexable inserts with a helical cutting edge. The highly effective edge was generated by the intersection of the shaped insert top (rake) face and the helical insert side (relief) surface. The design of the HELIMILL tools formed a constant positive rake and a constant relief along all cutting lengths. This feature immediately caused a significant reduction in power consumption and ensured a smooth cut. The HELIMILL heralded a new design approach that is considered today as the acknowledged format in indexable milling, and positioned the shaped surfaces of an insert into the forefront. The wording “HELI” reflects the helical cutting edge as a significant factor in the advancement of these indexable milling families.
  • Does ISCAR provide indexable milling cutters for machining aluminum?
    Yes. ISCAR has developed an entire comprehensive range of indexable milling cutters, designed specifically for the efficient machining of aluminum. Each family of these high-quality cutters features integral or lightweight body designs, unique principles of carbide insert clamping, structures with adjustable cartridges, various ground and polished inserts with different corner radii and, most popular in aluminum machining, inserts with polycrystalline diamond (PCD) tips. The vast majority of the cutters have inner channels for coolant supply through the body. The ISCAR HELIALU line of indexable milling tools enables efficient high speed machining (HSM) of aluminum, ensuring powerful metal removal rates (MRR).
  • The term “high positive” is often used when speaking about indexable milling cutters. What does it mean?
    Generally, this term relates to rake angles of an indexable milling cutter. Advances in powder metallurgy have resulted in the production of helical-cutting-edge inserts with a rake face that is “aggressively” inclined with respect to the insert cutting edge. This causes a significant increase in the positive rake angles (normal and axial) of a cutter carrying the inserts. The definition “high positive” emphasizes this feature. Note: This definition reflects the current state of the art. As the production of tools with cemented carbide inserts does not deplete its own resources, we may assume that the “high positive" of today will be considered as “normal” tomorrow.
  • Cemented carbide is a main cutting material for indexable inserts. ISCAR provides a rich variety of carbide grades. Where can I find basic information about the properties of a grade, recommended cutting speeds and application range?
    ISCAR offers a range of electronic and printed catalogues to reference guides that contain this information and specify the structure of a grade (substrate type, coating), the application range in accordance with ISO standards and the range of cutting speeds. Contact ISCAR representatives in your region for details and assistance.
  • Do the indexable milling cutters have internal channels for coolant supply?
    Most of the indexable milling cutters introduced recently feature an inner channel for coolant supply to each insert directly through the cutter body.
  • There are face shell mills that do not have these channels. If an internal coolant supply is necessary, how I can modify the mills?
    In most cases, this modification is not needed. Instead, ISCAR proposes clamping screws with adjustable nozzles to provide a simple solution to the problem. The screws not only secure the shell mills on arbors but provide effective coolant supply directly in the cutting zone and improve chip evacuation. A nozzle, the movable part of the screw, allows easy adjustment of coolant supply depending on the depth of a mill countersink depth, insert sizes or application needs.
  • How I can guarantee applying correct torque for tightening clamping screws that secure inserts in the milling cutters?
    In indexable milling lines, ISCAR provides two types of torque keys: with adjustable and fixed torque value. The first type allows the user to set torque within an available range, while the second type features a fixed torque value that is already preset. Information about which torque is necessary for tightening screws, which secure the inserts, can be found in catalogues, technical guides and leaflets. In addition, this data is now printed on the milling cutter body as a mark detail.
  • What is better for control productivity – varying the feed or the depth of cut within acceptable limits?
    It should be noted that the question has no unambiguous answer and depends on several factors. However, in general, under the same MRR, increasing the feed coupled with reduced depth of cut is more favorable than the opposite combination (lesser feed with deeper cut) because it normally results in greater tool life.
  • How can I find a more efficient indexable milling cutter for my applications?
    If you know the application parameters, ITA (ISCAR Tool Advisor), a computer-aided search engine, can be a very effective tool. This software is free and it may be installed even on your smartphone. If your question relates to more broad issues and considerations about selecting a suitable family of cutters, we have specific recommendations regarding priorities – please contact our representatives for assistance.
  • What is turn-milling?
    Turn-milling is a process whereby a milling cutter machines a rotating workpiece. This method combines milling and turning techniques and has many advantages.
  • What are the advantages of turn-milling comparing with classical turning?
    • In turning, machining non-continuous surfaces features interrupted cutting that results in unwanted impact load, poor surface finish and early tool wear. In turn-milling, the tool is a milling cutter that is intended exactly for interrupted cuts with cyclic load.
    • When turning materials with long chips, chip disposal is difficult and identifying the correct chipbreaking geometry of a cutting tool is not simple. The milling cutter used in turn-milling generates a short chip that considerably improves swarf handling.
    • In turning eccentric areas of rotating components (crankshafts, camshafts, etc.), off-center masses of the components cause unbalanced forces that adversely affect performance. Turn-milling with its low rotary velocity of a workpiece significantly diminishes and even prevents this negative effect.
    • In turning, the rotation of heavy-weight parts, which defines the cutting speed, is limited by the characteristics of the main drive. If the drive does not allow rotation of large masses with required velocity, then the cutting speed will be far from the optimal range; and will resulut in low turning performance. Turn-milling provides a way to overcome the above difficulties effectively.
  • How I can calculate cutting data for turn-milling?
    The calculation method is shown in the March 2017 issue of “Welcome to ISCAR’s World”, a collection of articles. The electronic version of the issue can be found also on ISCAR’s site catalogs. If necessary, please contact our local representatives in your area – they will be glad to help with this issue.
  • What is the difference between radial chip thinning and axial chip thinning?
    Chip thinning refers to decreasing maximum chip thickness hmax compared to feed per tooth fz.
    Two factors cause this decrease:
    • Cutting geometry of a milling tool, specifically the tool cutting edge angle χr when it is less than 90° ("axial chip thinning"). Good examples of axial chip thinning are fast feed milling and machining 3-D surfaces at shallow depth of cut by ball nose or toroidal-shape milling tools.
    • Influence of width of cut ae. If ae in peripheral milling and face milling is smaller than the radius of the milling tool, hmax becomes lower than fz. This effect is known as “radial chip thinning”. Understanding chip thinning is very important. Maintaining necessary chip thickness requires appropriate increase of feed per tooth and is a key element for correctly programmed fz.
  • What is a slab mill?
    A slab mill is a type of a cylindrical (plain) milling cutter – a milling tool with helical cutting teeth on its cylindrical periphery. Slab mills generally feature large sizes and have a central bore for arbor mounting, mainly in horizontal milling machine tools. Slab mill length is considerably greater than its diameter. These mills are intended for machining an open surface (mostly plane) of a workpiece when the surface width is less than the mill length. Slab mills were very common in the past but today they are used quite rarely.
  • What is “roll-in entering” a machined workpiece in milling?
    Roll-in entering (or, simply, rolling in) is a method of approaching a material in milling. In rolling in, a milling cutter enters the material by arc that causes a gradual growth of mechanical and thermal load on a cutting edge. This approach cut significantly contributes to machining stability and improves tool life. Rolling in is contrary to the traditional straight entering, when the load suddenly increases.
  • What are the advantages and disadvantages of clamping inserts in milling cutters by wedge?
    The main advantages of clamping indexable inserts in a milling cutter by wedge are quick and easy insert replacement or changing a worn cutting edge of the insert (the insert indexing). Clamping by wedge is more common for indexable face mills, especially large-sized. These mills usually work in tough conditions and often become hot. Machine operators prefer the wedge clamping design for such mills.
    However, the wedge, an additional part above the insert in the cutter structure, produces an obstacle for chip flow in the cutter chip gullet, which worsens chip evacuation and reduces cutter performance. This is a major disadvantage of wedge clamping. Intensive contact between the chips and the wedge results in the detrition wear of the latter and shortens its tool life.
    Profile Milling
  • What is the difference between profile milling, milling contoured surfaces and form milling?
    Generally, these definitions mean the same thing and relate to milling 3-D surfaces. Such kind of machining is often named in shop talk as simply profiling.
  • Which industrial sectors are characterized by a great number of profile milling operations?
    First, it is the Die and Mold industry, then Aerospace but almost every branch requires profile milling tools in a varying degree, too.
  • Which types of tools are the most popular for profile milling?
    In rough milling for “pre-shaping” further 3-D surfaces, process planners use different tools and even general-duty 90° milling cutters. Fast Feed milling cutters* are very efficient means for high-efficiency roughing. However, most of profile milling operations relate to toroidal and ball nose milling cutters because they ensure correct generation of a needed shape in every direction.

    * refer to the appropriate section in FAQ session
  • Are inserts with chip splitting action in ISCAR’s profile milling products?
    Yes. Moreover, exactly from MILLSHRED, a family of indexable milling cutters with round inserts, the serrated cutting edge of ISCAR milling inserts was started its way.
  • What is the effective cutting diameter of a profile milling tool?
    In profile milling, sue to the shaped, non-straight form of the tool, a cutting diameter is a function of a depth of cut; and it is not the same for different areas of the tool cutting edge that is involved in milling. The effective diameter is the largest true cutting diameter: maximum of the cutting diameters of these areas. In calculating cutting data, it is very important to consider the effective diameter, because the real cutting speed relates to the effective diameter, while the spindle speed refers to the nominal diameter of a tool.
  • Which types of profile milling tools ISCAR provides?
    ISCAR line of profile milling tools comprises Fast Feed*, toroidal, and ball nose cutters in the following design configurations:
    • tools with indexable inserts
    • solid carbide endmills
    • replaceable milling heads with MULTI-MASTER* adaptation

    * refer to the appropriate section in FAQ session
  • What is restmilling?
    Productive milling proposes applying more durable and rigid tools for high metal removal rate. In many cases the form and the dimensions of the tools do not allow for a cut in some area; for example, the corners of a die cavity. The remainder of the material in the areas is removed by restmilling – a method under a technological process where a tool of smaller diameter cuts the areas with residual stock.
    Solid Carbide Endmills (SCEM)
  • Does ISCAR provide solid carbide endmills for machining all groups of engineering materials?
    ISCAR’s SOLIDMILL line consists of various families of solid carbide endmills that are intended for machining different materials: steel, stainless steel, cast iron, etc. The line offers a rich variety of tools covering all application groups under ISO classifications P, M, K, N, S and H.
  • Which types of solid carbide endmills does ISCAR offer as standard products?
    ISCAR’s standard solid carbide endmill products include 90° endmills, ball nose cutters, and tools for high feed (fast feed) milling, chamfering, and deburring. ISCAR also offers families of endmills designed specifically for high speed machining that apply trochoidal milling techniques.
  • What are the advantages of the trochoidal milling method?
    Usually, trochoidal milling is applied to machining slots and pockets. In trochoidal milling, a fast-rotating tool moves along an arc and “slices” a thin but wide layer of material. When the layer is removed, the cutter advances deeper into the material radially and then repeats the slicing. This method ensures uniform tool engagement and stable average chip thickness. The tool experiences constant load, causing uniform wear and predictable tool life. The small thickness of sliced material significantly reduces heat impact on the tool and ensures an increase in the number of tool teeth. This method results in a very high metal removal rate with considerably decreased power consumption and improved tool life.
  • What is a "trochoid"?
    "Trochoid", or "trochoidal curve", is a general name for a curve described by a fixed point on a circle as it rolls along a straight line or curves without slipping.
  • What is the secret of CHATTERFREE geometry?
    CHATTERFREE represents a design utilized in several ISCAR solid carbide endmill families. The main CHATTERFREE features are unequal angular pitch of cutter teeth and variable helix angle. This concept results in substantially reducing or even eliminating vibrations during cutting, which significantly improves performance and tool life.
  • What is a variable helix?
    The term "variable helix" refers to the helix angle in vibration-free designs of solid carbide endmills (SCEM), as are found in ISCAR CHATTERFREE products. A typical SCEM features helical teeth and the helix angle determines the cutting edge inclination of a tooth. In traditionally designed endmills, the helix angle is the same for all flutes, but it varies in vibration-free configurations.
    The term “variable helix” is commonly understood to represent two design features: 1) Combining flutes with unequal helix angles where the angles are constant along every flute.
    2) Helix angle varies along the flute.
    However, the term “variable helix” is correct only in relation to design feature 1 and the term “different helix” should be used to specify design feature 2.
  • Why are FINISHRED endmills often referred to as “Two in One”?
    FINISHRED endmills feature four flutes, two serrated teeth and two continuous teeth. This facilitates the integration of two cutting geometries into a single tool: rough (serrated teeth with chip splitting action) and finish (continuous teeth), so gaining the “two in one” appellation. By running at rough machining parameters, semi-finish or even finish surface quality can be achieved. One such tool can replace two rough and finish endmills, reducing cutting time and power consumption while increasing productivity.
  • Does ISCAR provide instructions for regrinding solid carbide endmills?
    Yes. All catalogues, as well as relevant technical leaflets and brochures, contain instructions for regrinding solid carbide endmills, and ISCAR local representatives are available to advise on this issue.
  • What is a length series?
    Solid carbide endmills of the same type and the same diameter often vary in overall length within a family. According to the length gradation, there are short, medium and long series. Additional series such as extra-short or extra-long can also be applied. As a general rule, short-length endmills ensure highest strength and rigidity whereas extra-long solid carbide endmills are intended for long-reach applications.
  • What is a slot drill?
    “Slot drill” is a name of an endmill that can cut straight down. Slot drills have at least one center cutting tooth and are used mainly to form key slots. Slot drills are typically two-flute mills, but they can have three and even four flutes.
  • ISCAR ball nose solid carbide endmills have two or four flutes (teeth). How should the correct number of flutes for a ball nose endmill be chosen?
    The all-purpose four flute ball nose solid carbide endmills provide a universal and robust production solution for various applications, especially for semi-finish and finish operations. Two flute endmills have a larger chip gullet, which makes them more suitable for rough machining as they ensure better chip evacuation. Two flute tools are also considered to be a workable method for fine finishing due to a lower accumulated error, which depends on the number of teeth. When milling with shallow depth of cut, calculating feed per tooth should take into consideration only 2 effective teeth; as the advantages of a multi-flute design are diminished.
  • Does the ISCAR solid carbide endmill line include miniature endmills?
    ISCAR solid carbide endmill lines include endmills with diameters of tenths of mm. For example, the standard ball nose endmills, which are intended for processing ribs for hard materials, start from a minimal diameter of 0.1 mm.
    MULTI-MASTER
  • How is a head mounted into a shank?
    A head has two surfaces: a short taper and a rear non-cutting face that determines the head location in a shank. The taper ensures high concentricity and the face – a face contact. The thread is intended for securing the head. Therefore the rear (tail) part of the head has two areas: tapered and threaded.
    During mounting, the head is initially rotated by hand and then is tightened by means of a key. The head has flats for applying a key.
  • What are the advantages of the face contact?
    First of all, the face contact considerably increases the stiffness of an assembled tool comprising a shank and a head and its ability to withstand impact loading so common in milling. This factor allows for stable cutting, minimizes vibrations, and reduces power consumption.
    Secondly, the face contact ensures high repeatability of the head overhang with respect to the shank. As a result, there is no need for an additional adjustment after replacing the head - no setup time – and an operator can change the head without removing the shank from a machine tool spindle.
  • What does “the initial gap” mean?
    When tightening a head, an operator starts by rotating the head by hand. The head then stops at some point and a small gap remains between the contact faces of the head and the shank. From this moment, further head tightening is possible only with the use of the key. Tightening of the head causes elastic deformation of the adjoining contact area of the shank section, in a radial direction. The above-mentioned gap is called "initial" and it is an important feature of the MULTI-MASTER connection. The gap value is several tenths of a millimeter, depending on the thread size.
  • Why does the MULTI-MASTER thread have a special profile?
    The MULTI-MASTER heads are produced from tungsten carbide. Although this is an extremely hard and heat-resistant material, it has lowered impact strength against, for example, high speed steel (HSS). Therefore, in designing a threaded tungsten carbide part, minimizing stress concentrators is one of the main problems to be solved.
    Additionally, the MULTI-MASTER thread connection has relatively small dimensions: the nominal diameters of the threads lay approximately within 4-15 mm. These sizes and the necessity to meet the strength requirements for the operational loads, can possibly limit the height of the thread profile.
    The above points make it problematic to use the standard threads and strongly dictate a special thread shape that will comply with specifications of the connection. That is why ISCAR designed the special-profile thread, which has been designated as “T-thread”.
  • What types of MULTI-MASTER heads does ISCAR offer?
    • End milling heads of various shapes – 90°, 45°, 60°, etc.
    • Profile milling heads having ball nose, toroidal, concave radii and other shapes
    • Heads for high-feed milling
    • Slot and groove milling heads for milling grooves for retaining or O-rings, T-slots, etc.
    • Thread milling heads
    • Center and spot drilling heads
    • Engraving heads
    The milling heads have various numbers of teeth (flutes), helix angles, and degrees of accuracy, as well as cutting geometry for effective machining of various engineering materials.
  • What is an economy-type end milling head?
    There are two types of MULTI-MASTER end milling heads.
    The first type of MULTI-MASTER end milling head is the same as the ISCAR standard solid carbide endmills but differs in overall and cutting edge lengths. A major advantage of this type of end milling heads is that there is a large variety to choose from (practically all the standard line of the solid mills). In finishing and milling hard materials, increasing the number of flutes makes cutting more stable and productive. The heads of the first type are produced from stepped cylindrical blanks by grinding.
    The second type of MULTI-MASTER end milling heads is the economy version; it is shaped beforehand by pressing and sintering with a small oversize. Further grinding defines the final shape of a head and its accuracy. The heads of this type have a high-strength tooth that makes it possible to substantially increase the feed per tooth in comparison with the heads of the first type. Pressing technology enables production of different complicated shapes; although making these from the stepped blanks is problematic. The economy-type heads have only two teeth.
  • Why do the MULTI-MASTER keys have two openings?
    Due to the design features of the heads, one of the openings, similar to openings of ordinary engineering wrenches, is intended for the multi-flute heads of the first type of MULTI-MASTER end milling head (see above) and the appropriate cylindrical blanks. The second shaped opening is designed for the economy-type heads.
  • Does the MULTI-MASTER family include hole making tools?
    Yes, it does. The family has 45°, 30° and 60° heads that are not intended only for chamfering, but also for spot drilling and countersinking. In addition, there are center drilling heads.
  • Is a center drilling head that is made from solid carbide, really a reasonable solution? There are various low-cost double-sided standard combined center drills and countersinks produced from HSS.
    When compared to the above-mentioned HSS combined drills and countersinks, the center drilling heads allow for a considerable increase in tool life. The heads are operated under higher cutting data and thus lead to higher productivity. Therefore, we advise checking the current production cost and then making a decision, taking all relevant factors into account.
  • What is the accuracy of the heads?
    The nominal diameter of the normal accuracy end milling heads has the following tolerance limits: e8 for multi-flute heads produced from blanks and h9 for the economy- type heads. The precise heads for finish profiling are made with tolerance limits for diameter h7 and the heads for milling aluminum – h6. The diametric tolerance for the cylindrical cutting area of the heads for chamfering, spot drilling and countersinking is h10.
  • What is the repeatability tolerance of MULTI-MASTER heads?
    As mentioned in the answer to question 2, one of the main advantages of the face contact is high repeatability, which ensures closed tolerance for the head overhang with respect to the contact face of a shank. The overhang limits are ±0.01 mm for the majority of the end milling heads.
  • Does ISCAR offer MULTI-MASTER heads intended for milling hardened steel?
    Yes. These heads are made from a high-strength and wear-resistant submicron carbide grade; and they have tight dimensional tolerances.
  • What are the main types of shanks and for which purpose should they be used?
    The shanks are available in different versions: smooth cylindrical and with a neck. The neck can be straight or conical.
    The smooth shanks and the shanks with a straight neck, called Type A shanks in MULTI-MASTER’s designation system, are general purpose shanks and are used for a variety of applications. There is also a reinforced version, intended mainly for milling keyways or high-feed milling (HFM). It is distinguished by flats on a shank body that make it suitable for clamping in Weldon-type adapters.
    Type B is a reinforced shank with a relatively short conical neck which has a taper angle of 5° on the side. It is characterized by increased strength of the durable body that defines its main application: heavy-duty machining.
    For long-reach machining at high overhang, the Type D shank with a long conical neck can offer a good solution. It has a taper angle of 1° on the side and is designed primarily for milling deep pockets and cavities, high steep walls, etc. This shank should not be used in heavy-load conditions.
    For short-reach applications, the MULTI-MASTER family offers shanks with a collet adaptation. These are mounted directly into a collet chuck instead of the spring collet. The direct mounting increases rigidity and accuracy, and reduces the overall overhang relative to the datum face of a machine tool spindle.
    The MULTI-MASTER family also includes smooth steel cylindrical shanks of considerable overall length (at least 10 diameters of the shank). These are intended primarily for producing specially tailored tools of various configurations by additional machining of the shanks in order to form the required shape. Such machining can be performed even directly by the customer. In fact, they are the blanks with an internal T-thread. For the convenience of additional machining operations (turning, sometimes external grinding, etc.), the shanks are provided with a center hole in the rear face.
    The MULTI-MASTER family contains a variety of extensions and reducers for connecting with other ISCAR systems of modular tooling (for example, FLEXFIT).
  • From what materials are the shanks made? How should the correct material be chosen?
    The shanks are produced from the following materials: steel, tungsten carbide and heavy metal (an alloy containing 90% and more of tungsten).
    In the context of functionality, a steel shank is the most versatile. Due to the considerable stiffness of tungsten carbide, a carbide shank is intended primarily for finishing and semi-finishing, machining at high overhang and milling internal circumferential grooves. In case of unstable cutting, applying a heavy metal shank can give good results because of the vibration-proof properties of heavy metal. However, heavy metal shanks are not recommended for heavy-duty machining.
  • Are the MULTI-MASTER tools suitable for coolant supply directly through the tool body?
    Yes, there is a design of the shanks with holes for internal coolant supply.
  • Can the MULTI-MASTER shanks be held in heat shrink chucks and collets?
    The carbide or heavy metal shanks (see the answer to question 14) are suitable for toolholding by the heat shrink method. As for the steel shanks, clamping them into heat shrink chucks and collets is not recommended.
  • Is it necessary to lubricate T-threads when mounting the heads into a shank?
    No. Do not apply lubricants to the MULTI-MASTER T-thread connection!
    Fast Feed Milling
  • For which type of fast feed milling cutters does ISCAR manufacture tools?
    ISCAR’s line of fast feed milling cutters comprises tools carrying indexable inserts, Multi-Master tools and solid carbide end mills.
  • Which milling operation is more effective for applying FF milling cutters?
    The most effective applications for FF milling cutters are rough milling planes, pockets and cavities.
  • What is the meaning of the “Triple F” or "FFF" that is often mentioned in ISCAR technical editions and presentations?
    "FFF" refers to fast feed face milling or fast feed facing. Rough milling planes is one of most the efficient and widespread applications for FF cutters. The operation usually relates to face milling, so the FFF acronym refers usually to fast feed face milling. FFF can also mean fast feed facing, as milling plane operations are often known as facing.
  • Fast feed milling is considered as a high-efficiency metal removal technique when machined workpieces are made from steel or cast iron. Can FF milling cutters be applied to machining difficult-to-cut materials like titanium or high temperature alloys?
    FF milling cutters may be used in machining difficult-to-cut materials. The cutting geometry in this case differs from the geometry of general-duty FF milling tools that are intended for steel and cast iron. In addition, feed per tooth is significantly smaller compared to machining steel and cast iron; however it is much higher than the feed values that are recommended for traditional methods.
  • What are MF milling tools?
    MF means “moderate feed”: moderate comparing with “fast” in FF milling but faster than the standard in traditional milling. The MF method is intended for increasing productivity when using slow low-power machines, milling heavy workpieces, etc.
  • The LOGIQ campaign introduced new families of indexable FF milling cutters with a diameter range typically covered by solid carbide endmills. Can these new cutters successfully compete with the solid carbide design concept?
    Yes. The design of the cutters ensures a multi-teeth tool configuration. Let’s consider the NAN3FEED mill family as an example. They have 2 and 3 teeth for nominal diameters 8 and 10 mm (.315 and .394”) correspondingly. In a cutter carrying replaceable inserts, only the insert - a small part of the cutter - is made from cemented carbide. This means that the indexable design consumes far less of this expensive material than a solid carbide solution. The NAN3FEED insert with its 3 cutting edges ensures triple edge indexing, which is also cost-effectiveness. As the insert is small, it is placed simply in a pocket via a key with a magnetic boss on the key handle. The economical efficiency and ease of use make the family competitive with solid carbide tools.
    Milling Slots and Grooves
  • Which tools are used for milling slots?
    Generally speaking, milling tools of different types – side milling cutters, endmills, extended flite (long-edge) milling cutters and even face mills – are suitable for milling slots and grooves. However, only the side milling cutters with teeth on face and periphery are designed especially for machining slots and grooves, while the others are intended for various milling operations. ISCAR’s line of slot milling tools comprises the side milling cutters.
  • What is the difference between “slot” and “groove”?
    The words “slot” and “groove” are often synonymous. But if “slot” usually relates to a narrow, comparatively long, mainly longitudinal opening that is usually open-ended (at least from one side); “groove”, as a rule, means a circular (called “undercut”) or helical channel. It is been said that “a slot is an open-ended groove”.
  • Slot milling tools are often referenced as slotting tools. Is this correct?
    The word “slotting”, commonly known as “slot milling”, is widespread in shop talk but the two actions are not identical or interchangeable. Slotting refers specifically to a stage in planning or shaping – a machining process where a single-point cutting tool moves linearly and piston wise, and a workpiece is fixed or moves only linearly concurrent with the tool.
  • Why are slot milling cutters called side and face milling cutters?
    A slot milling cutter has teeth on its face and periphery, and features a cutting face and sides for the simultaneous machining of three surfaces: the bottom and the two sidewalls of a slot.
  • What are the main types of slot milling cutters?
    The slot milling cutters differ in their adaptation (mounting methods). They have either arbor hole or shank-type configurations or, alternatively, interchangeable cutting heads for modularly assembled tools.
  • What is ISCAR’s program for slot milling cutters?
    ISCAR is engaged in developing slot milling cutters in various fields:
    - Cutters carrying indexable inserts
    - Assembled Multi-Master slot milling tools with replaceable heads
    - Assembled T-SLOT milling cutters with replaceable solid carbide cutting heads
  • Which slot is defined as narrow?
    The term “narrow slot” generally defines a deep slot of small width. A more rigorous but empirical rule considers a “narrow slot” to be the slot with a width less than 5 mm and a depth of at least 2.5 times the width.
    Extended Flute Cutters
  • Why “extended flute” cutters?
    The cutting blade of an extended flute cutter consists of a set of indexable inserts that are placed gradually with a mutual offset of one another. Compared to an ordinary indexable mill whose length of cut is limited by the cutting edge of its insert, the cutting length of the extended flute cutter is significantly larger – it is “extended” due to the set of inserts.
  • What are the other technical terms for extended flute cutters?
    Extended flute cutters are also referred to as long-edge cutters and porcupine cutters (known as “porkies” in shop talk).
  • What are the main applications for extended flute cutters?
    Extended flute cutters are designed for high-performance rough milling: milling deep shoulders (known as “deep shouldering” in shoptalk), deep pockets and cavities (“pocketing”), and wide edges (“edging”).
  • Can extended flute cutters be applied to semi-finish operations?
    Yes. There are solutions that ensure this type of machining. For example, ISCAR HELITANG FIN LNK cutters carrying tangentially clamped peripherally ground inserts were designed especially for semi-finish milling.
  • Why do many types of indexable inserts for extended flute cutters feature a chip splitting design?
    Extended flute cutters work in heavy-load conditions. The following factors considerably improve cutter performance, which is why a chip splitting geometry is often integrated into the extended flute cutters’ design:
    • Chip splitting results in a wide chip being divided into small segments, which improves chip evacuation and chip handling.
    • The action of chip splitting strengthens vibration dampening of a cutter.
    • In many cases, chip splitting reduces cutting forces and power consumption, and leads to less heat generation during milling.
    • The small segments have fewer tendencies to be re-cut; this greatly improves rough milling of deep cavities and increases tool life.
  • What are the design configurations of ISCAR’s extended flute cutters?
    The ISCAR standard line of extended flute cutters comprises various designs:
    • Shell mills
    • Mills with cylindrical shanks (smooth or with flats, known as “Weldon-type”)
    • Mills with tapered shanks (7:24, HSK)
    • CAMFIX polygonal taper shank and replaceable cutting heads with a FLEXFIT connection
  • Can ISCAR’s extended flute cutters incorporate internal coolant supply channels?
    Most of ISCAR’s extended flute cutters have an internal channel for coolant supply through the body of the cutter.
  • Does ISCAR recommend extended flute cutters for milling titanium?
    Yes. Milling titanium usually involves removing considerable machining stock. It is a process with a significant buy-to-fly ratio and a large amount of metal needs to be removed. Extended flute cutters possess significant performance advantages in this area and their use can dramatically cut cycle time.
    Milling Gears and Splines
  • Does ISCAR provide tools for milling gears and splines?
    ISCAR’s current tool program, for milling spur gears with straight teeth and splines, has been developed to include three types of cutter:
    • cutters with indexable inserts
    • cutters with replaceable cutting heads based on the T-SLOT concept
    • cutters with replaceable MULTI-MASTER cutting heads
  • For which method of generating teeth are ISCAR’s milling tools intended?
    At present, ISCAR produces tools to generate tooth profiles by form milling.
  • When talking about generating a tooth profile, what is meant by “form milling”?
    Form milling is one of the methods for generating tooth profiles. In form milling, a milling cutter with a working shape like the contour of a tooth space, machines every tooth individually; and a workpiece is indexed through a pitch after generating one space.
  • Are there other methods of generating tooth profiles, apart from form milling?
    The principal methods (in addition to form milling) include gear hobbing, which uses a hob, a cutter with a set of teeth along a helix that mills the workpiece and that rotates together with the workpiece in a similar way to a worm-wheel drive; gear shaping with the use of a gear-shaping cutter, a rotating tool that visually resembles a mill; and by power skiving - a technique that combines gear milling and gear shaping. There are also other methods of generating teeth profiles, such as gear broaching, gear grinding, and gear rolling.
  • Is milling gear teeth the final operation of a gear-making process?
    In general, milling gear teeth is not the final operation in the gear-making process. After this operation, it is necessary to remove burrs and then the sharp edges of the teeth should be rounded or chamfered, for better engagement. Gear rounding, and gear chamfering operations are necessary to avoid quenching gears with sharp edges, which may cause various micro cracks that affect gear life. In addition, milling teeth ensures parameters that feature only gears of relatively low accuracy. As manufacturing precise gears demands tougher characteristics of accuracy and surface finish, other processes such as gear shaving, gear grinding, gear honing, etc., are also applied.
  • Usually, form gear milling relates mainly to individual and low-batch production. Why do manufacturers of general-purpose cutting tools, including ISCAR, include form gear milling cutters in their program for standard lines?
    With batch manufacturing, milling gear teeth is made on specific gear hobbing machines as gear hobbing productivity is substantially higher. However, advanced multifunctional machine tools increasingly widen the range of machining operations that can be performed. Technological processes developed for these machines are oriented to maximize machining operation for one-setup manufacturing, creating a new source for more accurate and productive manufacturing. Milling gears and splines is one of the operations suitable for performing on the new machines.
    These new machines require appropriate tooling and manufacturers of general-purpose cutting tools are reconsidering the role of gear-milling cutters in their programs for standard product lines.
  • What is the module in gearing?
    The module (modulus) is one of the main basic parameters of a gear in metric system. It is measured in mm. The module m of a gear with pitch diameter d and number of teeth z is the ratio of the pitch diameter to the number of teeth (d/z).
  • Does the inch (Imperial) system of gearing also use the module as a basic parameter in gearing?
    The inch (Imperial) system operates another basic parameter: the diametral pitch. This is the number of gear teeth per one inch of the pitch diameter. If a gear has N teeth and it features pitch diameter D (in inches), diametral pitch P is calculated as N/D. Sometimes, when specifying gears in inch units, the so-called English module is used. In principle, this module has the same meaning as the module in the metric system, e.g. the ratio of the pitch diameter and the number of teeth; however, the pitch diameter should be taken in inches and not in millimeters like in the metric system.
  • What is the difference between gear and splines?
    Gears in a gear train are intended for transmitting rotational movement between 2 shafts (while the axes of the shafts are not always parallel) and, in most cases, this transmission is combined with changing torque and rotational speed. The gears are used also for transforming rotational movement into linear movement. A splined joint is a demounted connection of two parts to transfer the torque from one to another. The torque is not changed here.
  • What is the difference between splines and serrations?
    Within this context, serrations represent a type of spline. The serrations feature V-shaped space between teeth. They are commonly used in small-size connections.
    Grooving
  • What is the first choice for Heavy Duty Grooving?
    • For Groove Only applications, use the DOVEIQGRIP TIGER insert that comes in widths of 10 - 20 mm
    • For Groove-Turn applications, use the SUMO-GRIP TAGB insert that comes in widths of 6 - 14 mm
  • What is the best chip former to machine ductile/gummy materials?
    Use the "N" chip former. It is offered in 3 - 8 mm widths for external GIMN inserts and 2 -5 mm widths for internal GEMI/GINI inserts.
  • What are the recommended grades to use on ISO-M / ISO-P materials?
    • The first choice for many applications is IC808
    • If you need a harder grade with more wear resistance use IC807
    • If you need a tougher grade with more impact resistance (Interrupted cuts) use IC830
  • What is the best grade to machine ISO-S (high temperature alloys)?
    • Use IC806 is to machine high temperature alloys as your first choice.
    • For harder ISO-S materials (HRC>35) use IC804
  • What grooving tool-holders should I use on Swiss-Type machines?
    Use our unique Side-Lock GEHSR/GHSR tools, which provide both front and back access that is much easier for Swiss-Type machines (as opposed to the conventional top clamping).
  • What are the most recommended grades/geometries for grooving/groove-turning cast iron?
    Use the TGMA/GIA inserts that feature a K-Land combined with grades IC5010 or IC428
  • What are the most recommended grades/geometries for grooving/groove-turning aluminum?
    • Use the GIPA/GIDA/FSPA inserts that feature a very sharp and positive cutting edge and a polished top rake combined with IC20 carbide grade or ID5 PCD
    • For widths of 6 – 8 mm, FSPA round inserts are the best choice due to their superior clamping method
  • What tools/inserts should I use for internal grooving in small diameter bores?
    • Bore diameter 2 – 10 mm: use PICCO inserts on PICCO ACE tools
    • Bore diameter 8 – 20 mm: use GIQR inserts on MGCH tools
    • Bore diameter 12 – 25 mm: use GEMI/GEPI inserts on GEHIR tools
  • How can I reduce vibrations?
    • Use the minimum possible overhang
    • Work with constant RPM
    • Reduce the RPM if needed
    • Reduce the insert width in order to decrease the cutting force
    • For widths of 6 and 8 mm, use WHISPERLINE Anti-Vibration blades
  • In what cases do you recommend the use of JETCUT tools with internal coolant?
    JETCUT tools are recommended for all coolant pressure levels (10 – 340 Bar) and all applications, as they deliver a repetitive and reliable coolant supply directly to the cutting edge at the exact point where it is needed, improving tool life and chip control
    Parting
  • What are ISCAR’s priorities for PARTING OFF?
    • For general applications up to 38mm part diameter, use DO-GRIP style double-ended inserts
    • Above 38mm: Use TANG GRIP style –single ended insert
    • Up to 40mm diameter: Use PENTA IQ , a highly economical insert with 5 cutting edges
  • What is the best grade for machining steel (ISO P)?
    • IC808/908
    What is the best grade for machining stainless steel (ISO M)?
    • C830/5400
  • What is the best insert geometry / chipformer for machining steel?
    • Use "C" geometry, for example DGN 3102C
    What is the best insert geometry / chipformer for machining stainless steel?
    • Use "J" geometry, for example DGN 3102J
  • What are the most recommended tools and inserts for machining miniature parts?
    • First choice is ISCAR DO-GRIP style (double-ended inserts) which has positive geometry, for example DGN 3102J & DGN 3000P
      * Use tools with Short Head dimensions, for example DGTR 12B-1.4D24SH
    • Second choice is to use ISCAR PENTA CUT, an economical insert with 5 cutting edges, for example :
      * PENTA 24N200J020 IC1008 (insert)
      * PCHR 12-24 (tool)
  • What is the best tool for heavy duty applications?
    • Use ISCAR TANG GRIP (single ended) insert – choose width according to part diameter
    • For heavy duty applications ISCAR offers 5-12.7mm insert widths
    • IC830 is the most suitable grade
    • Recommended insert geometry /chipformer is "C" type
  • How to reduce the bur on the part?
    • Use an R or L style of insert - these inserts have a lead angle, so the cutting edge is not straight
    • Also use a positive cutting rake, for example: DGR -3102J-6D (6D =6 degrees lead angle)
    • It is highly recommended to reduce the feed by 50% at the final cut
  • How to improve insert lifespan?
    Analyze the failure phenomena and choose grade accordingly:
    Wear: use a harder grade such as IC808 or 807
    Breakages: choose a harder grade such as IC830
  • Which is the best insert for an interrupted cut?
    Use a negative cutting rake, "C" chipformer and IC830 grade
  • How to improve chip control when long chips appear?
    • Select the correct chipformer and cutting parameters in order to obtain good chip formation
    • Choose a more aggressive chipformer
    • To increase feed, please refer to ISCAR user guide
  • How to improve part straightness and surface?
    • Use neutral insert and a stable tool with the minimum overhang needed
    • Adjust the cutting parameters
    Drilling
  • What is the recommended coolant flow rate?
    Depends on diameter. For example, the minimal flow rate for 6 mm SUMOCHAM is 5 liters per minute. For 20 mm, the minimal flow rate require is 18 liters per minute. For more information, please refer to SUMOCHAM user guide in our catalogue, page 491.
  • What is the recommended coolant pressure?
    Depends on diameter and tool length. For example, the minimal pressure for 6 mm SUMOCHAM on 8xD is 12 bar. For 25 mm SUMOCHAM on 12xD, the minimal pressure required is 4.5 bar. For more information, please refer to SUMOCHAM user guide in our catalogue, page 491.
  • What straightness can be achieved with the SUMOCHAM line?
    With a stable set-up, deviation may vary from 0.03 mm to 0.05 mm for each 100 mm of drilling depth. Important: Achieved results may vary due to machine, fixture, adaptation, etc.
  • What is the correct deep drilling cycle with the pre-hole and the next tool?
    In order to avoid mistakes, it is best to prepare the pre-hole with the same geometry that you intend to use for the subsequent deep drilling operation. For a more detailed explanation, please refer to our catalogue, page 492.
  • Is it possible to make boring operation with SUMOCHAM?
    No, the SUMOCHAM family is not designed for boring operations. Failure of the tool and insert may occur.
  • What is the recommended geometry for titanium?
    The first choice is ICG. The second choice is ICP.
  • Is it possible to regrind SUMOCHAM heads?
    Yes, ICP/ICK/ICM/ICN geometries can be reground up to three times. Please see a detailed explanation on pages 502-504 in our catalogue. Note: FCP/HCP/ICG/ICH geometries can be reground only at TEFEN.
  • What is the maximum permitted run-out for SUMOCHAM?
    To achieve best performance and tool life, radial and axial run-out should not exceed 0.02 mm. A detailed user guide can be found in our catalogue, starting on page 490.
  • Is it possible to use SUMOCHAM for interrupted cut operations?
    SUMOCHAM cannot withstand interrupted cut operations. Loss of clamping force of the tool may happen, eventually leading to falling out of the insert.
  • What solution does ISCAR recommend for hard materials?
    For hard materials we recommend our SCD-AH solid carbide drills made from IC903 grade, or a semi-standard option for SUMOCHAM line, the ICH heads.
  • What type of adapter is recommended?
    The recommended adapter is the one that is most suited for the tool's shank. For example, if the shank is round, the most accurate adapter would be of the HYDRO type. Please refer to page 829 in our catalogue.
  • What should be the maximum exit be for the SUMOCHAM exit hole?
    The exit for the materials should not be more than 2-3 mm less than the diameter edge of the insert.
  • What is your recommended solution for aluminum machining?
    Answer: Depends on the application. SUMOCHAM line has ICN inserts, which offer a dedicated solution for rilling non-ferrous materials.
  • What are the criteria to look for to indicate when SUMOCHAM heads are worn out?
    It is best to measure wear on a microscope. Additional indicators for wear are illustrated on page 493 in our catalogue.
  • Which hole is considered as "short" and which as "deep"?
    Commonly used terms “short” and “deep” holes do not have a strict definition. It is widely accepted that drilling a hole of diameter d and (10…12)×d or higher in depth relates to deep drilling, while holes having depth up to 5×d, are short.
    In the terminology used by ISCAR, only a drilling depth of 12×d and higher is considered as deep. Consequently, the holes with shallower depths are short.
  • What is a cutting length series of drills?
    The drills vary in their cutting length. In general, tool manufacturers normalize the drills by cutting length series (short, regular, etc.), according to the ratio "cutting length/drill diameter". At ISCAR, drills intended for machining short holes are usually divided into the following length series: short (up to 3×d), long (4×d and 5×d) and extra-long (8×d and 12×d).
  • Why is a center drill referred to as a "countersink" and even as a "spot drill"?
    A center drill is needed for forming a conical hole in workpieces. This hole is used for supporting the workpieces by the centers of machine tools. One of the methods for forming conical holes is countersinking - machining by a specially designed cutter, a countersink. In fact, the center drill performs a combination of two operations simultaneously: drilling and countersinking. Therefore, the center drill is often referenced as a “combined countersink”. Sometimes, a center drill is considered a spot drill; however this specification is not strictly correct. A spot drill only drills but a center drill performs two operations: drilling and countersinking, therefore “spot a hole” and “drill a center hole” are not the same.
  • In center drilling, does a Multi-Master replaceable solid carbide head offer a real alternative to reversible high-speed steel (HSS) drill bits?
    Reversible HSS center drill bits are the most popular tools for center drilling: they are simple, always available for purchase, and feature low prices. The Multi-Master replaceable solid carbide head enables significant increases in cutting speed and feed, resulting in higher productivity and reduced machining costs, especially in cases of machining difficult-to-cut material. In addition, the tool life of the head is much longer. A brief economical calculation will show the preferred alternative for each case.
  • Is a chip-splitting cutting geometry suitable for drills of a relatively small diameter?
    A chip-splitting cutting geometry may be used in drilling tools. There are different drill cutting edge designs with chip splitting grooves, for example the SUMOCHAM ICG heads. Splitting chips into small segments improves chip evacuation and cutting speed. Under the same cutting conditions, a straight-style edge ensures better surface finish. Therefore, chip-splitting geometry is suitable mainly for rough drilling operations.
    Reaming
  • When is a reaming operation required?
    A reaming operation is needed when the tolerance or/and surface finish requirements are tight and can't be achieved by drilling or boring.
  • For what tolerance field are the standard reamers suitable?
    Standard ISCAR reamers are suitable for IT7 field.
  • Are the standard reamers suitable for all materials?
    Standard reamers are suitable for most materials, but for the ISO N and ISO S material groups, it is preferable to consult the technical department for the most suitable solution.
  • What is the average tool life for a reamer?
    Since there are many different factors that affect its tool life (such as material, coolant, tolerance, runout etc.), it is difficult to estimate tool life and each case should be investigated individually.
  • Is it possible to ream without any coolant?
    No. It is impossible to ream without coolant; the most optimal situation is working with internal coolant but reaming with external coolant is also an option.
  • What recommended stock material should be left over before reaming?
    The recommended stock material depends on the machined material, reamer diameter and the tool used for hole preparation. In general, it can range from 0.15 to 0.4 mm per diameter.
  • What is the highest spindle runout possible for a reaming operation?
    In general, the highest spindle runout possible for reaming is around 0.01mm, but this also depends on the size and tolerance requirement. Above 0.01mm, the customer should use an ADJ system for runout compensation and adjustment.
    ISO
  • How to increase productivity for super alloys and Ni-based materials with ISCAR Ceramic Grades?
    ISCAR has a wide range of ceramic grades, such as the IW7, for machining super alloys and Ni-based materials.
    Our ceramic grades have the ability to work ten times faster in cutting speed - from 150M/min up to 450M/min - which is ten times higher than any conventional carbide inserts. This dramatically increases productivity.
  • What is ISCAR’s first choice in chip formers for steel machining?
    ISCAR introduces three new chipformers for finishing medium and rough turning of steel: F3P, M3P and R3P.
    The chipformers, combined with ISCAR’s SUMO TEC grades, deliver higher productivity, longer tool life, improved workpiece quality, and more reliable performance. The new chipformers generate less heat and avoid the problem of chips attaching themselves to cutting tools and components. Chips are broken down into smaller pieces, preventing them from tangling around the workpiece and enabling more efficient removal from conveyor belts.
  • How to improve chip control with the CBN insert?
    CBN inserts are mainly used for machining hard materials with high hardness levels from 55 and up to 62 RC . Conventional CBN inserts offer a wide range of brazed and flat tips that produce long and curled chips during the turning/machining of hard steel. The result is long chips that scratch the work piece and damage the surface quality. The ISCAR solution is a new CBN insert with grinded chip breaker on the cutting edge, providing excellent chip control in medium to finishing applications with high surface quality.
  • How to reduce vibrations on a boring bar with a high overhang of more than 4xBD?
    Throughout the world, machinists have to deal with the presence of problematic vibrations on a daily basis. To help solve these difficulties, ISCAR’s Research and Development division has produced an anti-vibration boring bar which contains the dampening mechanism inside the body. This reduces and even eliminates vibrations when using boring bars with a high overhang. The new anti-vibration line is called WHISPERLINE.
  • How to increase productivity in gray cast iron machining with ISCAR Ceramic Grades?
    Gray cast iron is recognized as the most popular material in the automotive industry. For machining gray cast iron, ISCAR offers a wide range of ceramic grades such as IS6 SiAlON inserts.
    The IS6 grade was developed in order to increase productivity in gray cast iron machining. The main advantage of our IS6 SiAlON ceramic grades is the ability to work three to four times faster in cutting speed, from 400M/min and up to 1200M/min, which is three times higher than any conventional carbide inserts. This increases productivity dramatically.
  • What is ISCAR’s first choice in chip formers for stainless steel?
    ISCAR is introducing 3 new chipformers: F3M, M3M and R3M for finishing, medium and rough turning stainless steel which, together with the most advanced SUMOTEC grades, provide higher productivity, tool life and performance reliability.
    The F3M chipformer has positive rake angles for smooth cutting, reduced cutting forces and insert wear, leading to dramatically increased tool life.
    The M3M chipformer is for medium machining of stainless steel with reinforced cutting edge and positive rake angle to reduce cutting forces and for smooth cutting.
    The R3M chipformer for chip breakers is for rough machining of stainless steel with reinforced cutting edge and positive rake angle to reduce cutting forces.
  • What is the effect of high-pressure coolant?
    The main advantage of the JETCUT tools is the ability to supply the coolant directly into the cutting zone to ensure high coolant efficiency in order to improve chip control, reduce heat and extend insert life.
    The high pressure coolant effect is mainly achieved in the machining of sticky and gummy materials such as super alloys, stainless steel, titanium etc…
    Ceramic Grades & Inserts
  • How to increase productivity of Ni-based and other superalloys with ISCAR ceramic grades?
    ISCAR has a wide range of ceramic grades, for example IW7, for machining Ni-based and other superalloys. Our ceramic grades have the ability to work 10 times faster in cutting speed, starting from 150M/min and going up to 450M/min which is 10 times higher than any conventional carbide inserts. This increases productivity dramatically.
  • Which chip formers does ISCAR recommend for steel machining?
    ISCAR has introduced three new chip formers for finishing medium and rough turning of steel: F3P, M3P and R3P. Combined with ISCAR’s SUMO TEC grades, the chip formers offer higher productivity, longer tool life, improved workpiece quality and more reliable performance. The new chip formers generate less heat and avoid the problem of chips attaching themselves to cutting tools and components. Chips are broken down into smaller pieces, preventing them from tangling around the workpiece and enabling more efficient removal from conveyor belts.
  • How to improve chip control with CBN inserts?
    CBN inserts are mainly for machining hard materials with high hardness - from 55 and up to 62 RC materials. Conventional CBN inserts offer a wide range of brazed and flat tips that produce long and curled chips during the turning machining of hard steel, resulting in long chips that scratch the work piece and damaging the surface quality. The ISCAR solution is a new CBN insert with grinded chip breaker on the cutting edge, which provides excellent chip control in medium to finishing applications with high surface quality.
  • How to reduce vibrations on boring bars with a high overhang of more than 4xBD?
    Throughout the world, machinists deal daily with problematic vibrations. ISCAR’s Research and Development department has designed and developed the WHISPERLINE range of anti-vibration tools to resolve this issue, including a boring bar with the dampening mechanism inside the body that eliminates and reduces vibrations when using bars with a high overhang.
  • How to increase productivity of gray cast iron with ISCAR ceramic grades?
    The most popular material in the automotive industry is gray cast iron. For machining gray cast iron, ISCAR offers a wide range of ceramic grades including IS6 SIALON inserts. Developed especially to increase productivity in gray cast iron, the IS6 SAILON grade can work 3 or 4 times faster in cutting speed - from 400M/min and up to 1200M/min which is 3 times higher than any conventional carbide inserts. This increases productivity dramatically.
  • What is ISCAR’s first choice in chip formers for stainless steel?
    ISCAR has introduced three new chip formers: F3M, M3M and R3M for finishing, medium and rough turning stainless steel. Combined with the most advanced SUMOTEC grades, the chip formers provide higher productivity, tool life and performance reliability. The F3M Chipformer has positive rake angles for smooth cutting, reduced cutting forces and insert wear, leading to dramatically increased tool life. The M3M Chipformer is designed for medium machining of stainless steel with reinforced cutting edge and Positive rake angle, to reduce cutting forces and ensure smooth cutting. The R3M Chipformer for chip breakers is designed for rough machining of stainless steel with reinforced cutting edge and positive rake angle, to reduce cutting forces.
  • What is the effect of high-pressure coolant?
    JETCUT tools have the ability to supply coolant directly into the cutting zone, ensuring high coolant efficiency, improved chip control, reduced heat and longer insert life. The high pressure coolant effect is applied to the machining of sticky and gummy materials such as super alloys, stainless steel, titanium etc.
    Threading
  • What is the most suitable grade for machining stainless steel?
    IC1007
  • What is the most suitable grade for machining HTA?
    IC806
  • What is the most suitable grade for low speed and unstable machines?
    IC228
  • What is the smallest recommended pass for thread profile?
    Bigger than honing size
  • Why doesn’t the chip breaker function?
    Apparently the depth of cut is too small, so the chip breaker is inefficient
  • How we can improve chip control?
    Improve chip control by selecting the correct infeed type:
    • Radial infeed
    • Flank infeed
    • Alternating flank infeed
  • How we can shorten process time?
    Use with multi tooth threading inserts (2M, 3M)
    Using two or three teeth combinations allow fewer passes and shorter cutting times. These are available for the most common profiles and pitches and are a good choice for economic threading in mass production.
  • What is the difference between partial to full profile insert?
    Partial profile:
    • Performs different thread standards and is suitable for a wide range of pitches that have a common angle (60º or 55º)
    • Inserts with a small root-corner radius suitable for the smallest pitch of the range
    • Additional operations to complete the outer/internal diameter is necessary
    • Not recommended for mass production
    • Eliminates the need for different inserts
    Full profile:
    • Performs complete thread profile
    • Root corner radius is only
    • Suitable for the relevant pitch
    • Recommended for mass production
    • Suitable for one profile only
  • How to select the correct anvil?
    Anvils for positive inclination angle are applicable when turning RH thread with RH holders or LH thread with LH tool holders.
    Anvils for negative inclination are used when turning RH thread with LH holder or LH thread with RH tool holder.
    Use AE Anvils for EX-RH and IN-LH Tool holders.
    Use Al Anvils for IN-RH and EX-LH Tool holders.
    Tool Material Grades
  • What is a tool material?
    In cutting tools, a tool material is the material from which the active (cutting) part of a tool is produced. This is the material that directly cuts the workpiece during machining.
  • How does ISCAR designate its tool materials?
    ISCAR’s system of designating tool material grades uses letters and numbers. The letters indicate the material group:
    IB – cubic boron nitride (CBN)
    IC – cemented carbide and cermet
    ID – polycrystalline diamond (PCD)
    IS – ceramics
    DT – cemented carbide with dual (CVD+PVD) coating
  • What is a carbide grade?
    A combination of cemented carbide, coating and post-coating treatment produces a carbide grade. Only one of these components - the cemented carbide - is the necessary element of the grade. The others are optional. Cemented carbide is a composite material comprising hard carbide particles that are cemented by binding metal (mainly cobalt).
    Most cemented carbides used for producing cutting tools integrate wear-resistant coating and are known as “coated cemented carbides”. There are also various treatment processes that are applied to already coated cemented carbide (for example, the rake surface of an indexable insert). “Cemented carbide” can refer both to the substrate of a coated grade and to an uncoated grade.
  • How does ISCAR classify carbide grades?
    The international standard ISO 513 classifies hard cutting material based on their reasonable applicability with respect to the materials. ISCAR adopted this standard and uses the same approach in tool development. Cemented carbides are very hard materials and therefore they can cut most engineering materials, which are softer. Some carbide grades demonstrate better performance than others in cutting tools applied to machining a specific class of materials.
  • The groups of application of carbide grades in accordance with ISO 513 include letters and numbers after the letter. What do they mean?
    The letters in the group of application define a class of engineering materials, to which a tool that is produced from a specific grade, can be applied successfully. The classification numbers show hardness-toughness ratio of the grade in an arbitrary scale. Higher numbers indicate an increase in grade toughness, while lower numbers indicate an increase in grade hardness.
  • What is SUMO TEC technology?
    SUMO TEC is a specific post-coating treatment process developed by ISCAR. The treatment has the effect of making coated surfaces even and uniform, minimizing inner stresses and droplets in coating. In CVD coatings, due to the difference in thermal expansion coefficients between the substrate and the coating layers, internal tensile stresses are produced. Also, PVD coatings feature surface droplets. These factors negatively affect a coating and therefore shorten insert tool life.
    Applying SUMOTEC post-coating technologies considerably reduces and even removes these unwanted defects and results in increasing tool life and greater productivity.
  • Why are PVD nano layered coatings considered so efficient and progressive?
    PVD coatings were introduced during the late 1980’s. With the use of advanced nanotechnology, PVD coatings performed a gigantic step in overcoming complex problems that were impeding progress in the field.
    Developments in science and technology brought a new class of wear-resistant nano layered coatings. These coatings are a combination of layers having a thickness of up to 50 nm (nanometers) and demonstrate significant increases in the strength of the coating compared to conventional methods.
  • The designation of ISCAR’s carbide grades usually starts from letters “IC”. Why is grade DT7150 (DO-TEC) designated differently?
    Coating technology features two principal directions - Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD). Technology development allows both methods – CVD and PVD – to be combined for insert coatings, as a means of controlling coating properties.
    ISCAR’s carbide grade DT7150 features a tough substrate and a dual MT CVD (Medium Temperature CVD) and TiAlN PVD coating. The grade was originally developed to improve the productive machining of special-purpose hard cast iron.
  • Why are several of ISCAR’s carbide grades referred to by customers as “sun tan” grades?
    Some PVD coated (like IC840 or IC882) and CVD coated (IC5820, for example) carbide grades, originally developed for machining ISO S and ISO M materials, feature a bronze chocolate color. The “sunbathed” appearance of the inserts produced from these grades resulted in the shop talk definition “sun tan” grade.
    Engineering Materials
  • When giving recommendations about cutting data, how does ISCAR classify engineering materials?
    ISCAR material groups are organized in accordance with international standard ISO 513 Classification and application of hard cutting materials for metal removal with defined cutting edges — Designation of the main groups and groups of application and technical guides VDI 3323 Anwendungseignung von Harten Schneidstoffen (English: Information on applicability of hard cutting materials for machining by chip removal). VDI (Verein Deutscher Ingenieure) is the Association of German Engineers.
  • The ISO 513 standard specifies cutting tools intended for machining stainless steel as the tools that apply to Group M. Is this correct?
    In ISO 513, Group M (yellow identification color) relates to the tools for machining stainless steel of austenitic and austenitic/ferritic (duplex) structure. Ferritic and martensitic stainless steel belong to Group P (blue color) and starting cutting data should be set accordingly.
  • Is machining titanium like machining austenitic stainless steel?
    Commercially pure titanium and, with some applications, α- or α-β- titanium alloys may be machined like austenitic stainless steel but not treated β- and near-β- alloys.
  • What is “titanium beta”?
    “Titanium beta” is an expression that occurs in aerospace industry lingo/shop talk. It can refer to two different materials - a β-annealed α-β- titanium alloy or, rarely, a β-alloy. Therefore the expression should be exactly specified before using it, or even avoided to prevent possible misunderstanding.
  • Why is the machinability of materials from ISO M and S groups considered together?
    These materials are difficult-to-cut materials and have common features that affect machinability: low thermal conductivity and high specific cutting force.
  • Does cast iron relate to ISO Group K?
    The majority of cast iron grades (grey, nodular, malleable) relate to Group K.
    When machining hardened or chilled cast iron, appropriate cutting tools (and corresponding cutting data) should be chosen as recommended for Group H.
    Austempered ductile iron (ADI) in its soft condition is connected with Group P.
    Austempered ductile iron (ADI) in its hardened condition is connected to Group H.
  • Which steel is pre-hardened and which is hard?
    Steel producers supply steels in different delivery conditions: annealed, pre-hardened, hardened. The loosely defined term "pre-hardened steel" relates to steel that is hardened and tempered to a hardness that is not too high - generally this is less than HRC 45. The terms "pre-hardened" and "hard steel" are allied to cutting tool development and the ability of the tools to cut material. Commonly, the steels can be divided into the following conditional groups depending on their hardness:
    • Soft (annealed to hardness up to HB 250)
    • Pre-hardened to two ranges:
      - HRC 30-37
      - HRC 38-44
    • Hardened to three ranges:
      - HRC 45-49
      - HRC 50-55
      - HRC 56-63 and more

    As for "hard steel", usually it refers to steel hardened to HRC 60 and more.
  • What is Ebonite and how to machine this material?
    Ebonite is a hard vulcanized rubber containing a high percentage of sulfur. For the purpose of identifying a suitable tool and appropriate cutting data, Ebonite is characterized by ISCAR material group 30 (ISO N application class). To machine Ebonite effectively, we advise following ISCAR’s recommendations for this group.
  • Are hard metal and heavy metal the same?
    No.
    In metalworking, "hard metal" is a commonly used name for cemented carbide, which is a sintered hard material based on wolfram (tungsten) carbide. Cemented carbide is often referred as simply tungsten carbide. It is the main cutting tool material used today.
    Heavy metals are metals with high atomic weight or density. In the metalworking industry, the term “heavy metal” usually refers to heavy metal alloys, which are sintered composite materials containing 90% or more tungsten.
  • What is the difference between duplex and super duplex stainless steels?
    Duplex stainless steel has a two-phase metallurgical structure: austenitic-ferritic, approximately in equal shares.
    Super duplex stainless steel is a type of duplex stainless steel that contains an increased percentage of chromium and molybdenum for better corrosion resistance.
    From a machinability point of view, these steels are hard-to-cut.
    Shop Talk (Professional slang)
  • Metal cutting, like other fields of industrial activity, has its own professional jargon that is often used in shop talk. We decided to devote a separate section to more common jargon, even though they may appear already in the other FAQ sections.

    Ball mill – a ball-nose milling cutter. The correct meaning of “ball mill” is a grinding device for grinding materials into powder.

    Bull-nose – a milling cutter, a replaceable milling head or insert of toroidal cutting profile.

    Cubic – metal removal rate (MRR) in cubic mm, cm or inches.

    Feed mill – a fast feed (high feed) milling cutter.

    Grade –a specific type of cutting tool material. In particular, “carbide grade” relates to a type of cemented carbide.

    High positive – a feature of cutting geometry that relates mainly to the rake angle of a tool. For tools with high positive geometry, the rake angle is significantly greater than common values.

    Inconel – Inconel is the trade name for a group of more than 20 metal alloys made by Special Metals Corporation. When followed by a number (e.g. Inconel 625), it is a specific material from a family of nickel-chromium-based high temperature alloys. Without a number following, Inconel often refers to a whole group of nickel-based superalloys.

    Nirosta – stainless steel, normally austenitic.

    Plunger – a plunge milling cutter.

    Porky (porcupine) – an extended flute (long-edge) indexable milling cutter

    Positive insert – this may relate to two different features of an indexable insert:

    1. Insert where the insert bottom face is smaller than the insert top face.

    2. Inclination of the insert cutting edge that generates a positive axial rake of a tool, when the insert is mounted in the tool.

    This dual meaning sometimes causes serious misunderstandings.

    Slocombe (Slocomb) drill – a center drill.

    Slotter – in milling, this term defines slot milling cutter; however it normally refers to a type of planing machine tool.

    Slotting – Originally, this term defined a machining process where a single-point cutting tool moves linearly and piston wise, and a workpiece is fixed or moves only in linear direction. However, today this term relates more to slot milling.

    Slotting cutter – Slot milling cutter (see above)

    Titanium beta (β) – in most cases it is a beta-annealed α-β-titanium alloy, although sometimes it means a β-titanium alloy.

    Whiskers - whisker-reinforced ceramic.

    Tool Holding
  • What is a tool holder?
    A tool holder is a device (a tool arrangement) for mounting a cutting tool in a machine tool. One of the tool holder ends carries the cutting tool while the other ends is clamped into the machine tool. Therefore the tool holder acts as an interface between the machine tool and the cutting tool.
  • Are the terms “tool holding” and “tooling” synonymous?
    “Tool holding” is also referred to as “toolholding” and usually relates to tool holding systems that comprise various tool holders, such as arbors, chucks or adaptors, and their accessories (extensions, reducers, rings, sleeves, etc).
    “Tooling” is a much broader definition. “Tooling” can refer to cutting tools together with tool- and work holding arrangements that are intended for a machine tool. “Tooling” relates sometimes to tool management and in certain circumstances it refers to tool holding systems.
  • Does ISCAR supply work holding devices?
    No, ISCAR does not supply work holding devices. ISCAR’s products are cutting tools, tool holding, and tool management systems.
  • Does ISCAR provide tool holders with polygonal taper shank?
    Yes. These tool holders are represented by ISCAR’s CAMFIX family.
  • What are the advantages of thermal (heat) shrink holders?
    The advantages of tool holding, based on clamping tools with cylindrical shanks with the use of heat shrink fitting, are as follows:
    • High accuracy
    • High rigidity
    • Excellent repeatability
    • Reaches deep cavities due to slim holder design
    • Balanced design and assembly’s symmetrical shape eliminate the production of centrifugal forces at high rotational speeds
  • Are ISCAR’s thermal shrink holders suitable for tools with steel shanks?
    Yes. ISCAR’s SRKIN thermal shrink holders are intended for clamping tools with shanks made from cemented carbide, high speed steel (HSS) and steel. The SRKIN product line is fitted DIN69882-8, which is the shrink holder market standard.
    ISCAR also produces SRK slim design shrink holders. SRK holders can be used for steel shanks but we recommend using them for carbide shanks.
  • Does ISCAR produce heating units for mounting cutting tools in thermal shrink holders?
    Yes, ISCAR produces the induction heating unit for thermal shrink tool holding. In addition to this unit, ISCAR provides its simplified, “starter” version, which was designed to help the end-user purchase the shrink holding technology in a low cost device.
  • What are the main design features of X-STREAM SHRINKIN products? In which field would applying these products be the most effective?
    X-STREAM SHRINKIN is a family of thermal shrink chucks with coolant jet channels along the shank bore. The family utilizes a patented design for holding tools with shanks, made from cemented carbide, steel or high-speed steel (HSS). The new chucks combine the advantages of high-precision heat shrink clamping with coolant flow, directed to cutting edges. X-STREAM SHRINKIN has already shown excellent performance in milling aerospace parts, particularly titanium blades and blisks (bladed discs), and especially in high speed milling. In machining deep cavities, the efficient cooling provided by the new chucks substantially improves chip evacuation and diminishes chip re-cutting.
  • What are the SPINJET products and where they are used?
    ISCAR’s SPINJET is a family of coolant-driven compact high speed spindles for small diameter tools. It is a type of “booster” for upgrading existing machines to high speed performers. Depending on pressure and coolant flow rate, the spindles maintain a rotational speed of up to 55000 rpm. The versatile SPINJET products have been successfully integrated in tooling solutions for milling, drilling, thread milling, engraving, chamfering, deburring, and even fine radial grinding. The SPINJET spindles are recommended for tools up to 7 mm (.275 in) in diameter, however the optimal diameter range is 0.5-4 mm (.020-.157 in).
  • Does ISCAR deliver tool holders with identification chips?
    ISCAR’s tool holders with HSK shanks incorporate holes for radio-frequency identification chips (RFID). ISCAR’s CAMFIX tool holders with polygonal taper shank of nominal size C4 (32 as specified by ISO 26623-1) and more are produced with this hole.
    ISCAR can provide RFID chip mounting for all types of tool holder by special request.
    Note: It is essential to adjust the tool holder after mounting an RFID chip.
  • Does ISCAR supply boring heads with digital displays?
    Yes. ISCAR’s ITSBORE family contains adjustable boring heads with digital displays. These heads feature high adjusting accuracy and a simple adjusting process. A clear digital display with a mm/inch value display selection helps to prevent human errors.
  • What is the difference between mandrel and arbor?
    There is no fundamental difference - both terms refer to a bar, usually rotating, that is used for mounting a machined workpiece or a cutting tool.
  • Does ISCAR supply tool holding devices for tapping?
    Yes. Tool holding products for tapping include quick-change ER-type collets, holders with straight shanks and with 7:24 taper shanks, for example:
    • GTI toolholders and straight shanks with floating compression/tension mechanism
    • GTIN compact product line for tappng based on ER collets
    • TCS/TCC quick-change system (part of the ITSBORE modular system)