1. What is the most important and decisive factor in selecting tool steel?
Answer: Forming method - there are two basic material types to choose from.
A) Hot working tool steels, which can withstand the relatively high temperatures of die casting, forging and extrusion.
B) Cold working tool steels, which are used for blanking and shearing, cold forming, cold extrusion, cold forging and powder pressing.
Plastics - Some plastics produce corrosive byproducts, such as PVC plastics. Factors such as condensation caused by long downtime, corrosive gases, acids, cooling/heating, water or storage conditions can also cause corrosion. In these cases, stainless steel is recommended.
Tool size - Pre-hardened steels are often used for large-sized tools. Through-hardened steels are often used for small-sized tools.
Number of tool use - Tools that are used for long periods of time (> 1 000 000 times) should use high-hardness steels with a hardness of 48-65 HRC. Molds that are used for medium to long periods of time (100,000 to 1,000,000 cycles) should use pre-hardened steel with a hardness of 30-45 HRC. Molds that are used for short periods of time (<100,000 cycles) should use soft steel with a hardness of 160-250 HB.
Surface finish - Many plastic mold manufacturers are interested in good surface finish. When sulfur is added to improve metal cutting performance, the surface quality is reduced. Steels with high sulfur content also become more brittle.
2. What is the primary factor affecting the machinability of a material?
Answer: The chemical composition of the steel is important. The higher the alloy content of the steel, the more difficult it is to machine. As the carbon content increases, the metal cutting performance decreases.
The structure of the steel is also very important to the metal cutting performance. Different structures include: forged, cast, extruded, rolled and machined. Forgings and castings have very difficult to machine surfaces.
Hardness is an important factor affecting metal cutting performance. Mold Master WeChat: 1828765339 The general rule is that the harder the steel, the harder it is to process. High-speed steel (HSS) can be used to process materials with a hardness of up to 330-400 HB; high-speed steel + titanium nitride (TiN) coating can process materials with a hardness of up to 45 HRC; and for materials with a hardness of 65-70 HRC, cemented carbide, ceramics, cermets and cubic boron nitride (CBN) must be used.
Non-metallic inclusions generally have an adverse effect on tool life. For example, Al2O3 (aluminum oxide), which is pure ceramic, is highly abrasive.
The last one is residual stress, which can cause metal cutting performance problems. It is often recommended to perform a stress release process after rough machining.
3. What are the components of the production cost of mold manufacturing?
A: Roughly speaking, the costs are distributed as follows:
Cutting 65%
Workpiece material 20%
Heat treatment 5%
Assembly/adjustment 10%
This also shows very clearly the importance of good metal cutting performance and a good overall cutting solution for the economic production of molds.
4. What are the cutting characteristics of cast iron?
A: Generally speaking, it is:
The higher the hardness and strength of the cast iron, the lower the metal cutting performance and the lower the life that can be expected from the blade and tool. Cast iron used for metal cutting production generally has good metal cutting performance for most types. Metal cutting performance is related to structure, and harder pearlitic cast irons are more difficult to machine. Flake graphite cast iron and malleable cast iron have excellent cutting properties, while ductile cast iron is quite poor.
The main types of wear encountered when machining cast iron are: abrasive, adhesive and diffusion wear. Abrasive wear is mainly caused by carbides, sand inclusions and hard casting skin. Adhesive wear with built-up edge occurs under low cutting temperature and cutting speed conditions. The ferrite portion of cast iron is most susceptible to welding to the insert, but this can be overcome by increasing the cutting speed and temperature.
Diffusion wear, on the other hand, is temperature-dependent and occurs at high cutting speeds, especially when using high-strength cast iron grades. These grades have a high resistance to deformation, resulting in high temperatures. This wear is related to the interaction between the cast iron and the tool, which requires some cast irons to be machined at high speeds with ceramic or cubic boron nitride (CBN) tools to obtain good tool life and surface quality.
Typical tool properties required for machining cast iron are: high thermal hardness and chemical stability, but also related to the process, workpiece and cutting conditions; cutting edge toughness, thermal fatigue wear resistance and edge strength are required. Satisfactory cutting of cast iron depends on how the wear of the cutting edge develops: rapid blunting means premature cutting edge fracture due to thermal cracks and notches, workpiece damage, poor surface quality, excessive waviness, etc. Normal flank wear, balanced and sharp cutting edges are what is generally strived for.
5. What are the main and common machining processes in mold manufacturing?
Answer: All mold manufacturing processes go through a cutting process, which should be divided into at least three types of processes: Roughing, semi-finishing and finishing, and sometimes even super-finishing (mostly high-speed cutting applications). Residual milling is of course a preparation for finishing after the semi-finishing process. It is very important to strive to leave evenly distributed allowances for the next process in each process. If the direction of the tool path and the workload rarely change rapidly, the life of the tool may be extended and more predictable. If possible, the finishing process should be performed on a dedicated machine tool. This will improve the geometric accuracy and quality of the mold with shorter debugging and assembly time. 6. What kind of tools should be mainly used in these different processes? Answer: Roughing process: round blade milling cutter, ball nose end mill and end mill with large tip arc radius. Semi-finishing process: round blade milling cutter (round blade milling cutter with a diameter range of 10-25 mm), ball nose end mill. Finishing process: round blade milling cutter, ball nose end mill. Residual milling operations: round insert milling cutter, ball end mill, vertical end mill.
It is very important to optimize the cutting process by selecting a specific combination of tool size, groove shape and grade, as well as cutting parameters and appropriate milling strategies.
For the high-productivity tools that can be used, see the mold manufacturing sample C-1102:1
7. Is there a most important factor in the cutting process?
Answer: One of the most important goals in the cutting process is to create evenly distributed machining allowances for each tool in each operation. This means that tools of different diameters (from large to small) must be used, especially in roughing and semi-finishing operations. The main criterion at all times should be to get as close as possible to the final shape of the mold in each operation.
Providing evenly distributed machining allowances for each tool ensures constant and high productivity and a safe cutting process. When ap/ae (axial cutting depth/radial cutting depth) remains unchanged, the cutting speed and feed rate can also be kept constantly at a high level. In this way, the mechanical action and workload on the cutting edge vary less, so less heat and fatigue are generated, thereby increasing tool life. If the subsequent operations are some semi-finishing operations, especially all finishing operations, unmanned or partially unmanned processing can be carried out. Constant material processing allowance is also a basic criterion for high-speed cutting applications.
Another favorable effect of constant processing allowance is that it has little adverse effect on the machine tool - guideways, ball screws and spindle bearings.
8. Why are round blade milling cutters most often used as the first choice for mold roughing tools?
Answer: If a square shoulder milling cutter is used for rough milling of the cavity, a large amount of step-shaped cutting allowance must be removed in semi-finishing. This will cause the cutting force to change and the tool to bend. The result is that uneven processing allowance is left for finishing, which affects the geometric accuracy of the mold. If a square shoulder milling cutter with weaker tip strength (with triangular blades) is used, unpredictable cutting effects will occur. Triangular or diamond blades also produce greater radial cutting forces, and because the number of blade cutting edges is small, they are less economical roughing tools.
On the other hand, round inserts can be used for milling in a variety of materials and in all directions. If used, they can provide smoother transitions between adjacent tool paths and can also leave smaller and more uniform machining allowances for semi-finishing. One of the characteristics of round inserts is that the chip thickness they produce is variable. This allows them to be used at higher feed rates than most other inserts. The main rake angle of the round insert changes from almost zero (very shallow cutting) to 90 degrees, and the cutting action is very smooth. At the maximum depth of cutting, the main rake angle is 45 degrees, and when cutting along a straight wall with an outer circle, the main rake angle is 90 degrees. This also explains why round insert tools are strong - the cutting load is gradually increased. Roughing and semi-roughing should always be preferred to round insert milling cutters, such as CoroMill 200 (see mold manufacturing sample C-1102:1). In 5-axis cutting, round inserts are very suitable, especially since it has no restrictions.
With good programming, round insert milling cutters can largely replace ball end mills. Round inserts with low run-out combined with finely ground, positive rake angles and light cutting geometries can also be used for semi-finishing and some finishing operations.
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9. What is the effective cutting speed (ve) and why is it so important for high productivity?
Answer: The basic calculation of the effective cutting speed on the actual or effective diameter is always very important in cutting. Since the table feed depends on the rotational speed at a certain cutting speed, if the effective speed is not calculated, the table feed will be calculated incorrectly.
If the nominal diameter value (Dc) of the tool is used when calculating the cutting speed, the effective or actual cutting speed is much lower than the calculated speed when the cutting depth is shallow. Tools such as round insert CoroMill 200 tools (especially in the small diameter range), ball nose end mills, large nose radius end mills and CoroMill 390 end mills (for these tools, see Sandvik Coromant's mold making catalog C-1102:1). As a result, the calculated feed rate is also much lower, which seriously reduces productivity. More importantly, the cutting conditions of the tool are lower than its capabilities and recommended application range.
When 3D cutting is performed, the diameter of the cut varies, which is related to the geometry of the mold. One solution to this problem is to define steep wall areas of the mold and shallow part areas with shallow geometry. If a dedicated CAM program and cutting parameters are compiled for each area, a good compromise and result can be achieved.
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10. What are the important application parameters for successful milling of hardened mold steel?
Answer: When finishing hardened mold steel with high-speed milling, a major factor to be observed is shallow cutting. The cutting depth should not exceed 0.2/0.2 mm (ap/ae: axial cutting depth/radial cutting depth). This is to avoid excessive bending of the tool holder/cutting tool and to maintain small tolerances and high precision of the machined mold.
It is also very important to choose a very rigid clamping system and tool. When using solid carbide tools, it is important to use tools with the largest core diameter (maximum bending rigidity). A rule of thumb is that if the diameter of the tool is increased by 20%, for example from 10 mm to 12 mm, the bending of the tool will be reduced by 50%. It can also be said that if the tool overhang/protrusion is shortened by 20%, the tool bending will be reduced by 50%. Large diameter and tapered toolholders further increase rigidity. When using ball-end end mills with indexable inserts (see mold manufacturing sample C-1102:1), the bending rigidity can be increased by 3-4 times if the toolholder is made of solid carbide.
When finishing hardened mold steel with high-speed milling, it is also very important to choose a special groove shape and grade. It is also very important to choose a coating with high thermal hardness such as TiAlN.
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11. When should down milling be used and when should reverse milling be used?
Answer: The main recommendation is: use down milling as much as possible.
In down milling, the chip thickness reaches its maximum value when the cutting edge is just cutting. In reverse milling, it is the minimum value. Generally speaking, tool life is shorter in reverse milling than in down milling, because the heat generated in reverse milling is significantly higher than in down milling. In up-cut milling, as the chip thickness increases from zero to maximum, more heat is generated because the friction on the cutting edge is greater than in down-cut milling. The radial forces are also significantly higher in up-cut milling, which has an adverse effect on the spindle bearings.
In down-cut milling, the cutting edge is mainly subjected to compressive stresses, which have a much more favorable effect on the carbide insert or solid carbide tool than the tensile forces generated in up-cut milling. There are exceptions, of course. When side milling (finishing) is performed with a solid carbide end mill (see tool in Die Sample C-1102:1), especially in hardened materials, up-cut milling is the first choice. It is easier to achieve tighter tolerance wall straightness and better 90-degree angles. The kerf is also very small if there is any misalignment between the different axial passes. This is mainly due to the direction of the cutting forces. If a very sharp cutting edge is used in the cut, the cutting forces tend to "pull" the tool towards the material. Another example where up-cut milling can be used is milling with an old manual milling machine, where the lead screw has a large gap. Up milling produces cutting forces that eliminate backlash, making the milling action smoother.
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12. Profile milling or contour cutting?
Answer: In cavity milling, the best way to ensure the success of the down milling tool path is to use a contour milling path. Milling cutters (such as ball-nose end mills, see mold manufacturing sample C-1102:1) often achieve high productivity along the outer circle of the contour milling because there are more teeth cutting on the larger tool diameter. If the machine tool spindle speed is limited, contour milling will help maintain cutting speed and feed rate. With this tool path, the workload and direction changes are also small. This is particularly important in high-speed milling applications and hardened material processing. This is because if the cutting speed and feed rate are high, the cutting edge and the cutting process are more susceptible to changes in workload and direction, which cause changes in cutting force and tool bending. Profile milling along steep walls should be avoided as much as possible. When down profile milling, the chip thickness is large at low cutting speeds. There is also the risk of edge chipping in the center of the ball end cutter. If the control is poor or the machine does not have a look-ahead function, it will not decelerate quickly enough and the risk of edge chipping is greatest in the center. Profile milling along steep walls is better for the cutting process because the chip thickness is at its maximum at a favorable chip speed.
To obtain the longest tool life, the cutting edge should be kept in continuous cutting for as long as possible during the milling process. Tool life is significantly shortened if the tool enters and exits too frequently. This increases thermal stress and thermal fatigue on the cutting edge. Modern carbide tools are more favorable to uniform and high temperatures in the cutting area than to large fluctuations. Profile milling paths are often a mixture of reverse milling and forward milling (zigzag), which means that the tool is frequently engaged and retracted during cutting. This tool path also has a negative impact on the quality of the mold. Each engagement means that the tool is bent and there is a lift mark on the surface. When the tool is withdrawn, the cutting forces and the bending of the tool are
Reduced, there will be a slight "overcut" of material in the exit section.
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13. Why do some milling cutters have to have different pitches?
Answer: Milling cutters are multi-cutting tools, and the number of teeth (z) can be changed. There are some factors that can help determine the pitch or number of teeth for different types of processing. Material, workpiece size, overall stability, overhang size, surface quality requirements and available power are factors related to processing. Tool-related factors include sufficient feed per tooth, at least two teeth in cutting at the same time, and the chip capacity of the tool, which are only a small part of them.
The pitch (u) of a milling cutter is the distance from a point on the cutting edge of the blade to the same point on the next cutting edge. Milling cutters are divided into sparse, dense and super dense pitch milling cutters. Most Coromant milling cutters have these 3 options, see mold manufacturing sample C-1102:1. Dense pitch means that there are more teeth and appropriate chip space, which can be cut at a high metal removal rate. Generally used for medium-load milling of cast iron and steel. Dense pitch is the first choice for general-purpose milling cutters and is recommended for mixed production.
A coarse pitch means fewer teeth and more chip space around the cutter circumference. Coarse pitch is often used for roughing to finishing steel, where vibration has a significant impact on the machining results. Coarse pitch is a real problem solver and is the first choice for long overhang milling, low-power machines or other applications where cutting forces must be reduced.
Super-close pitch cutters have very small chip space and can use higher table feeds. These cutters are suitable for cutting intermittent cast iron surfaces, roughing cast iron and cutting steel with small excess, such as side milling. They are also suitable for applications where cutting speeds must be kept low. Milling cutters can also have uniform or unequal pitches. The latter refers to the unequal spacing of the teeth on the tool, which is also an effective solution to vibration problems.
When vibration is a problem, it is recommended to use coarse pitch unequal pitch cutters as much as possible. With fewer blades, the possibility of increased vibration is less. Small tool diameters can also improve this situation. A combination of well-adapted groove shapes and grades should be used - a combination of sharp cutting edges and tough grades.
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14. How should the milling cutter be positioned for optimum performance?
Answer: The cutting length is affected by the position of the milling cutter. Tool life is often related to the cutting length that the cutting edge must carry. A milling cutter positioned in the center of the workpiece has a short cutting length. If the milling cutter is moved off center in either direction, the arc of the cut is longer. Remember that there must be a compromise in how the cutting forces act. With the cutter positioned in the center of the workpiece, the direction of the radial cutting forces changes as the blade cutting edge enters or exits the cut. The machine spindle clearance also exacerbates vibrations, causing the blade to vibrate.
By moving the cutter off center, a constant and favorable cutting force direction is achieved. The longer the overhang, the more important it is to overcome all possible vibrations.
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15. What measures should be taken to eliminate vibrations during cutting?
Answer: When vibration is a problem, the basic measure is to reduce the cutting forces. This can be achieved by using the right tool, method and cutting parameters.
Follow the proven recommendations below:
- Choose a milling cutter with a coarse pitch or uneven pitch.
- Use positive rake angle, low cutting force insert geometry.
- Use the smallest possible milling cutter. This is especially important when milling with damping adapters.
- Use inserts with small edge radii (ER). From thick to thin coatings. Use uncoated inserts if necessary. Use tough insert grades with fine-grained matrix.
- Use high feed per tooth. Reduce speed and maintain table feed (equal to the larger feed per tooth). Or maintain speed and increase table feed (larger feed per tooth). Do not reduce feed per tooth!
- Reduce radial and axial depth of cut.
- Choose a stable toolholder, such as Coromant Capto. Use the largest possible adapter size for best stability. Use tapered extensions for maximum rigidity.
- For large overhangs, use damping adapters in combination with sparse, unequal pitch milling cutters. Mount the cutter so that it is directly connected to the damping adapter.
- Move the cutter off center of the workpiece. - If using a tool with an even number of teeth - remove one insert every other tooth.
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16. What are the most important steps to take to balance the tool?
Answer: The typical steps involved in balancing the tool during the entire cutting process are as follows:
- Measure the imbalance of the tool/holder assembly.
- Reduce the imbalance by changing the tool, cutting it to remove some mass, or moving the weight on the holder.
- These steps must often be repeated, including rechecking the tool and re-adjusting it precisely until balance is achieved.
Tool balancing also involves several instabilities in the process that have not been discussed. One of them is the fit between the holder and the spindle. The reason for this is often a measurable gap when clamping, or chips or dirt on the taper. This causes the taper to be positioned differently each time. Even if the tool, holder and spindle are in good condition in all aspects, if there is contamination, it will cause imbalance. In order to balance the tool, costs must be added to the cutting process. If tool balancing is important to reduce costs, each specific situation should be analyzed.
However, there is more work to be done in selecting the right tool for a well balanced tool. The following points should be considered when selecting a tool: - Purchase high-quality tools and toolholders. Choose toolholders that have been pre-balanced.
- It is best to use tools that are short and as light as possible.
- Check tools and toolholders regularly for signs of fatigued threads and deformation.
The tool imbalance that is acceptable to the process is determined by the conditions of the process itself. These conditions include the cutting forces during the cutting process, the balance of the machine tool, and the degree to which these two factors affect each other. Experimentation is the best way to find the best balance. Run several times with different imbalance values, for example, start with an imbalance value of 20 g mm or less. After each run, repeat the test with a more balanced tool. The best balance should be such a point beyond which further improvement of the tool balance will not improve the surface quality of the workpiece; or such a point at which the process can easily guarantee the specified workpiece tolerances.
The key is to always focus on the process, rather than targeting the dynamic balance grade-G value or other arbitrarily determined balance value. The goal should be to achieve the most efficient process possible. This involves weighing the cost of tool balancing against the benefits gained from it, so a reasonable balance should be struck between the costs and benefits.
For more detailed technical information on tool balancing, please contact your local Coromant representative.
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17. What toolholders should I use to get the best possible results in conventional and high-speed cutting applications?
Answer: During high-speed machining, the centrifugal forces are very high, which causes the spindle hole to slowly grow larger. This has a negative impact on some V-flange toolholders, which only contact the spindle hole on the radial surface. The larger spindle hole causes the tool to be pulled into the spindle under the constant tension of the pull rod. This may even cause the tool to stick or reduce the dimensional accuracy in the Z axis direction.
Tools that contact the spindle hole and the end face at the same time, that is, tools that cooperate radially and axially at the same time, are more suitable for cutting at high speeds. When the spindle hole expands, the end face contact prevents the tool from moving upward in the spindle hole. Tools with hollow shanks are also susceptible to centrifugal forces, but they have been designed to increase with the spindle bore at high speeds. The contact between the tool and the spindle in both radial and axial directions provides good clamping rigidity, allowing the tool to cut at high speeds. The Coromant Capto interface, which uses a unique elliptical triangular short cone design, has better performance in transmitting torque and high-productivity cutting.
Comparison table of spindle surface contact at high spindle speeds
Spindle speed ISO 40 HSK 50A Coromant Capto C5
0 100% 100% 100%
20 000 100% 95% 100%
25 000 37% 91% 99%
30 000 31% 83% 95%
35 000 26% 72% 91%
40 000 26% 67% 84%
When high-speed cutting is arranged, a tool system consisting of a symmetrical tool and tool holder combination should be used as much as possible. There are several different tool systems available. The tool holder is first heated to expand the hole, and the tool is clamped after it cools down. This is an interference fit system. For high-speed cutting, this is the best and most reliable way to fix the tool. This is firstly because of its very small runout; secondly, this connection can transmit high torque; thirdly, it is easy to build custom tools and tool assemblies; and finally, the tool assembly assembled in this way has extremely high overall rigidity.
Another outstanding and very versatile tool clamping device is Coromant's high-precision power chuck - CoroGrip. This tool holder system covers all applications from roughing to super finishing. One chuck can clamp all types of tools from face milling cutters to drills using straight shanks, Whitworth groove or side pressure chucks. Standard spring chucks, such as those available for hydraulic (HydroGrip), BIG, Nikken, NT, can be used for CoroGrip chucks. The runout at 4XD is only 0.002 – 0.006 mm. The clamping force and torque transmission are particularly high, and its balanced design makes it perfect for high-speed cutting (< 40 000 rpm). For more information on tool holders, please refer to the mold manufacturing sample C-1102:1.
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18. How can I cut corners without the risk of vibration?
Answer: The traditional method of cutting corners is to use linear cutting (G1) with discontinuous transitions at the corner. This means that when the tool reaches the corner, it must slow down due to the dynamic characteristics of the linear axis. There is a short pause before the motor changes the feed direction, which generates a lot of heat and friction. The long contact length leads to unstable cutting forces and often undercuts the corner. The typical result is vibration - the larger and longer the tool, or the greater the total tool overhang, the greater the vibration.
The best solution to this problem:
Use a tool with a smaller corner radius than the corner radius. Use circular interpolation to generate the corner. This machining method does not produce a pause at the block boundary, which means that the tool movement provides a smooth and continuous transition and the possibility of vibration is greatly reduced.
Another solution is to use circular interpolation to generate a slightly larger corner radius than specified on the drawing. This is very advantageous, so that sometimes larger tools can be used in roughing to maintain high productivity.
The remaining machining allowance in the corners can be fixed milled or circular interpolated with a smaller tool.
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19. What is the best way to start cutting a cavity?
Answer: There are 4 main methods:
Pre-drilling of the starting hole, and pre-drilling of the corners is also possible. This method is not recommended: it requires an additional tool, and this tool also takes up space in the tool chamber. From a cutting point of view, the tool will vibrate unfavorably due to the cutting forces when passing through the pre-drilled hole. When using pre-drilled holes, tool damage is often caused. Using pre-drilled holes also increases chip re-cutting.
If a ball end mill or round insert tool is used (see mold manufacturing sample C-1102:1), pecking milling is usually used to ensure that the full axial depth can be cut. The disadvantages of using this method are chip evacuation problems and the use of round inserts will produce very long chips.
One of the best methods is to use linear ramping in the X/Y and Z directions to achieve full axial depth cutting.
Finally, circular interpolation milling can be performed in a spiral form. This is a very good method because it produces a smooth cutting action and requires only a small starting space.
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20. What is the definition of high speed cutting?
Answer: The discussion of high speed cutting is still somewhat confusing. There are many opinions and many ways to define high speed cutting (HSM). Let's look at a few of these definitions:
High cutting speed cutting
High spindle speed cutting
High feed cutting
High speed and high feed cutting
High productivity cutting
We describe our definition of high speed cutting as follows:
HSM is not simply high cutting speed. It should be considered as a process that is processed with specific methods and production equipment.
High speed cutting does not require high speed spindle cutting. Many high speed cutting applications are performed with medium speed spindles and large size tools.
If finishing hardened steel at high cutting speeds and high feeds, the cutting parameters can be 4 to 6 times the normal.
HSM means high productivity cutting in roughing to semi-finishing, finishing and super finishing of small size parts.
As part shapes become more complex, high-speed cutting becomes more and more important.
Currently, high-speed cutting is mainly used on machines with a taper of 40.
For more information about high-speed cutting, see Mold Manufacturing Application Guide C-1120:2. See Mold Manufacturing Application Guide C-1120:2.
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21. What is the goal of high-speed cutting?
Answer: One of the main goals of high-speed cutting is to reduce production costs through high productivity. It is mainly used in finishing operations, often for machining hardened mold steel. Another goal is to improve overall competitiveness by reducing production time and delivery time.
The main factors in achieving these goals are:
Mold processing in one (or less) clamping.
Cutting improves the geometric accuracy of the mold while reducing manual labor and shortening mold trial time.
Use CAM systems and shop-oriented programming to help develop process plans, and improve machine tool and shop utilization through process plans.
For more information about high-speed cutting, see Mold Manufacturing Application Guide C-1120:2. See Mold Manufacturing Application Guide C-1120:2.
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22. What are the practical advantages of high-speed cutting?
Answer: The tool and workpiece can be kept at low temperatures, which in many cases prolongs the tool life. On the other hand, in high-speed cutting applications, the cutting volume is shallow and the cutting edge is engaged for a particularly short time. That is, the feed is faster than the time for heat propagation.
Low cutting forces result in small and consistent tool deflection. This, combined with the constant machining allowance required for each tool and operation, is one of the prerequisites for efficient and safe machining.
Since the typical cutting depth in high-speed cutting is shallow, the radial forces on the tool and spindle are low. This reduces the wear on the spindle bearings, guides and ball screws. High-speed cutting and axial milling are also a good combination, it has low impact on the spindle bearings, and with this method, tools with longer overhangs can be used without much risk of vibration.
High-productivity cutting of small-sized parts, such as roughing, semi-finishing and finishing, has good economy when the total material removal rate is relatively low.
High-speed cutting can be used in general finishing.
