To develop optimal sharpening modes, it is necessary to link the sharpening conditions with the microgeometry of the sharpened instrument and the physicomechanical properties of the surface layer (hardness, structure of the modified layer, its depth), and all these parameters with the wear resistance of the sharpened blade when cutting wood.
The final assessment of the sharpening modes was revealed as a result of testing the sharpened knives for wear resistance when milling wood. Studies have revealed the impact on the quality of sharpening of individual elements of the sharpening mode (cross feed, speed of rotation of the circle, longitudinal feed, cooling, etc.) and on this basis develop recommendations for sharpening modes.
Cross feed. The thickness of the metal being grinded in one pass of the circle is the most important parameter of the sharpening mode. The increase in lateral feed dramatically affects the depth of structural changes in the surface layers of the blade, the increase in grinding power, the specific productivity of the wheels and the cleanliness of processing.
Studies show that an increase in cross feed from 0.02 to 0.04 mm / dv. a stroke, i.e., 2 times (grinding productivity also increases by 2 times) causes an increase in grinding power by 29%, a reduction in the specific grinding work by 36%, a decrease in the specific productivity by 12%. These data indicate a low economic efficiency of sharpening at small cross feeds. For the purity of the treatment, which deteriorates with an increase in the thickness of the layer being removed, this is not significant in the presence of a nursing and finishing operation. In the process of nursing, regardless of the values of the cross feed in the first stage of sharpening, a constant and best grinding cleanliness is achieved for a circle of a given grain. The importance of nursing is not only that an improvement in cleanliness is achieved, but also that by nursing a defective surface layer that appears during sharpening, if it is shallow, or reduce its thickness.
The limitation on the choice of transverse feeding is not the purity of the surface obtained, which is easily corrected in the last passes, but the thickness of the surface layers in which significant structural transformations occurred, and the specific productivity of the grinding wheel. The final recommendations on the depth of grinding when sharpening knives from steel 9H5VF, P4, P9 are made taking into account this position.
Circle speed. Experiments show that to prevent structural transformations in the surface layer and a possible reduction of burrs on the blade, it is necessary to choose the speed of the grinding wheel depending on the chemical composition of the steel, the characteristics of the wheel, the angle of grinding, the magnitude of the transverse and longitudinal feed. Incorrect application in all cases, the speeds indicated on the grinding wheel. Increasing the speed of a circle without taking into account the influence of other sharpening factors leads to an increase in the depth of the defective layer of the surface being sharpened and to an increase in the thickness of the burr.
Traverse. Experiments show the feasibility of increasing the speed of the longitudinal feed, as it increases the productivity of sharpening and increases its quality. In this case, the grinding wheel, being a source of instantaneous high temperatures, is less in contact with the treated surface, and as a result of reducing the duration of the thermal process, the depth of structural transformations decreases. Upper limit of longitudinal feed is not set. Practically it is determined by the constructive capabilities of the machine.
What factors affect the wear of scissors
Sharpening hairdressing scissors is carried out as needed. In one case, the sharpening may last for six months, in the other, the instrument will last two years. The average is one year.
During this period, the tool can perform the work of high quality, but only under the condition of a correctly completed sharpening.
Well sharpened scissors
Objectively, a number of factors affect the timing of scissors:
- Accuracy treatment.
- Features of operation (male, female master and station wagon get different wear).
- Loads that fall on scissors (number of customers per day).
- Hair treatment before cutting (wetting from a spray, washing).
- Peculiarities of the clientele (hair of Asian or Negroid type is tougher than European ones, this reproaches wear and tear as well as hair cut of gray vitreous hair).
- Storage method
- The specificity of the use of disinfectants (type of disinfection, compliance with the rules of its implementation).
- The quality of the material from which the scissors are made, and the approach of the manufacturing company to the production process.
- The choice of the master, which is sharpening hairdressing and manicure tools.
Recommendations for choosing a master and training
When choosing a master for servicing the tool, it is important to give preference to professionals.
The profession of a tool sharpener who works with a hairdressing and manicure and pedicure tools is not the same thing as a work of a tool sharpener or a mechanic. The fact is that the tools of a beauty salon worker need precise processing, the cutting edges must have the correct shape. If the scissors are not processed in a specialized workshop, the tool will be damaged.
Sharpening closers work only with:
- hairdressing scissors for a direct cut,
- thinning scissors,
- knives for hair clippers,
- various types of tweezers for manicure and pedicure,
- shoulder blades, scissors and other varieties of manicure and pedicure tools.
The cost of sharpening hairdressing and manicure tools on the machine
Sharpening or finishing each tool implies an individual approach. Therefore, the cost in each case will be their own. In addition, the price of the service depends on the type of instrument.
Taking into account the information in the table, we can conclude that sharpening thinning shears differs in cost from working with straight blades.
Often the masters come straight to the salon with the suggestion of sharpening or fine-tuning right on the spot. Despite all the practicality of this approach, you should not trust this sharpener.
High-quality work requires a high concentration, the presence of specialized equipment and comfortable conditions, which a beauty salon designed for another type of service cannot provide.
All about scissors: information for hairdressers, as well as manicure and pedicure
Hairdressers, manicure-pedicure often ask the question: what tools to buy for work? This is the most sensitive issue. After all, you want to spend good money by spending money. The word is good - a concept difficult to understand, until those very good tools fall into your hands, and you will not work with them. But I will try to tell you about the main features of the tools.
There are a lot of cheap tools on the market. So cheap that you just get lost. There are expensive, "would be money" to buy them.
As a rule, craftsmen buy the tools of a well-known company, and beginners try to choose cheaper. Usually those who are enrolled in courses from the district employment service do so. It is good if the course instructor tells you the places where you can buy them.
All masters, without exception, are concerned about the same question: how the tools will work after the purchase, no matter how expensive or cheap they are. Here I will surprise you: even cheap tools can work on par with expensive ones.
How long will the tools last?
If you use the tools correctly and as intended - you can work them from six months to two years or more. Usually a year can not think about anything, then you need to sharpen.
There are many objective factors affecting the life of the tool.
Factors affecting tool life
- your ability to handle a tool
- what kind of master you are: hairdresser, male, female or combined,
- how many customers do you have in a shift,
- contingent of people (with hard or soft hair),
- whether you wash your hair before cutting or just wet it
- Do you use idle strokes during the haircut (closing the scissors without cutting the hair),
- how neat you are at work, do you drop scissors, do you use leather cases with a clasp,
- how to fold and store the tool after work,
- what disinfectants do you use
- whether you give your instrument to other masters or not (I strongly recommend it: drop it and you will be out of work),
- how sharpened are the tools, a professional or a “stray” master (money bouncer),
- manufacturer of your tools and the quality of steel.
As you can see, there are not so few of them, only the main ones are listed here.
Where to buy a tool, no matter what: hairdresser, manicure or pedicure
If you are taking courses, you can buy a tool from a master teacher. They usually do this. You can also go to hairdressing and consult with those who are already working and know what tools are needed and where to buy them. You can also buy tools at a professional exhibition, there is usually a large selection. But it is best to buy in a specialty store. They will give you a guarantee and a check. Your consumer rights will be protected.
What tools to buy?
There is such a rule: it is better for novice hairdressers to buy not very expensive tools, but for manicure pedicure masters it is better to buy expensive ones at once.
- Buy tools only from well-known companies (for example, Jaguar, ProLine, Mertz, KEDAKE). Basically, 1st or 2nd grade. 3 or 4 class is not necessary to take, since beginners do not have enough experience with such tools. That's when you learn to work well, gain experience - then buy.
- If you go to paid courses, to elite masters, then there often rules require you to have good tools.
- Expensive tools are not always good, and they may not suit you.
- When choosing straight scissors note: the thickness of the shears should be the same, especially at the tips. If one web is thicker and the other is thinner, this will lead to uneven wear of the edge of one of the web. Always look at the gap between the blades in front of a bright light: it should be from the tip of the scissors to the screw. And also check the clearance under the load, it is done like this: close the blades, take the scissors in your right hand, hold them horizontally in front of a bright light and look at the gap between the blades, press down on the scissors' rings so that the gap between the blades will disappear if the gap starts smoothly disappear from the tip to the middle, and there is a gap in front of the cog - then this is a more or less successful choice, but if there is no clearance in the middle, but there is a gap in front of the tip, then the scissors will begin to wring hair during work. If you learn this method of choice, you can choose the right scissors.
- When choosing thinning shears: the gap between the canvases on the clearance should not be too large. Too large a gap, during operation, will beat a straight blade and leave deep grooves on the cutting edge. Such scissors will spoil themselves.
- Try to choose a "filler" with small teeth - too large will remove a lot of hair. The grooves on the tips of the teeth should be the same at all. They are v-shaped, rectangular (n - upside down) and with small depressions. With shallow grooves, less hair is removed.
- Usually choose scissors in five and a half inches, they are perfect, mainly for women's haircuts, for men - six inches and more. Combined, as universal, five and a half inches. If you do not know how to define inches, then here: the thumb width on the hand is 25.4 mm., This is 1 inch. Calculate how many fingers will fit from the tip of the scissors to the edge of the rings, and you will know how many inches. Usually, on Jaguar scissors, the last two digits in the number indicate how many inches, or inches are written on a straight canvas, and the class of scissors is indicated by squares.
- There are good KIPE scissors, they still have a globe drawing near the screw. Pretty good quality, and their steel is not worse than expensive. There are also ProLaine scissors - also very good. And the “filer” of this same company leaves much to be desired. Their canvases are quite massive and wide, this increases their stiffness and during haircuts they can fairly confidently take large strands of hair.
Novice masters manicure-pedicure:
- Do not take cheap scissors, as they can be coated with zinc or nickel. As soon as the coated layer comes off, the scissors will start to rust, and this will start from the tips - the main working element.
- Note that manicure tools, unlike barbershops, are sold anywhere: in the markets, in underground passages, in kiosks, just from the hands, therefore, in order not to blunder when buying, ask about the tool manufacturer what steel it is made of ( steel 40Х13, in the people - "medical").
- Fear those who offer cheap tools for big money. Usually this happens at trade shows.
- Buy only professional tools. No consumer goods. Take it as a rule.
Instructions for using the tool
Tools require a careful attitude. There are rules that will help you extend their life. So, we list them:
- do not beat the scissors on the comb to shake the hair off them
- do not dump tools in a pile - it can damage the cutting edges,
- do not throw tools, but put them carefully,
- take only the handles, not the canvases, so as not to cut yourself,
- do not leave in the disinfectant solution longer than necessary, it can dull the cutting edges,
- Regularly lubricate the tools as described in the instructions for them (especially for hair clippers),
- make sure that the hairdressing scissors has a working tension of the cloths so that the blades do not dangle when they are closed - this leads to rolling of the cutting edges on both blades,
- Never use a gypsy needle to sharpen scissors, you will only make it worse
- Sharpen the tool in a timely manner from an experienced (if possible) professional sharpener-closer,
Where to sharpen tools?
Sharpen tools only in the workshop that specializes in sharpening just hairdressing, manicure and pedicure tools, and not in the workshop on sharpening kitchen knives and tailoring scissors, because each tool requires a certain approach.
There are some craftsmen who travel to hairdressing salons and salons and sharpen tools on the spot. It is very easy to take a grinding machine to put an abrasive or diamond wheel on it and make a grinding, but on such motors, with circles, there is insufficient rotational speed (usually it is 1250 revolutions per minute instead of the required 3000 rev / min.). These machines are not balanced, vibrate strongly. This is a signal that sharpening will not be of high quality. When sharpening nail scissors use diamond files or diamond nails, but it still does not provide the correct sharpening, because it does not create the correct geometric surfaces of the cutting edges, the front surface, the rear auxiliary surface, the sharpening angle, the cutting angle.
Using the services of such masters, you always run the risk: you may be spoiled or may not be spoiled by tools, but, as a rule, they spoil because they grind by hand without using special equipment, where you can withstand all the necessary sharpening angles. Such sharpeners have distant ideas about the specifics of your work, for them the main thing is your money. Usually these are people of related professions: turners, grinders, sharpeners, millers, mechanics of mechanical assembly, etc. They know that there is such an opportunity to “zashib” money, sharpening your tools, and do not miss it. But they don’t even have a clue how thin and hard the work is, it’s a completely different approach and a different technology. Such a specific experience has been gained over the years. The sharpener should have such qualities as: endurance, perseverance, patience, good eyesight, good coordination of movements. The sharpener should not shake hands, he can not afford to drink and smoke. And, of course, he must have the necessary knowledge, while working, always observe safety precautions. In the end, he must have a talent, a flair of metal, a creative approach. He must continually improve skills and technology. He must have a developed sense of conscience and decency: do everything for himself. After all, this is all displayed on his work - on your instrument.
Perhaps, this will seem too fanatical to someone, but this is justified. As a result, the client receives high-quality tools and gives money for them with pleasure. To such a master will always come, as you quickly get used to the good. But you don't want to pay for refining twice.
To date, the correct sharpening of straight hairdressing scissors, such as KEDAKE, requires 43 operations, special grounding, mandrels, to maintain all of the original grinding angles. On the correct sharpening takes from 3 to 5 hours. This is a 4th grade job. It takes from 8 to 12 hours to grind thinning shears, it is at least 80 operations and 4th grade, with slicing in both cases (with straight scissors).
Imagine how much work you need with scissors that you messed up?
How to determine what your scissors can ruin?
Ask these questions:
What is the grain on the grinding wheel? (it should be from 80 to 100 microns.),
What is the number of revolutions of the grinding wheel per minute? (should be 2950 rpm)
How do you sharpen: by hand or on special devices? (on special devices),
Do you disassemble scissors before sharpening? (unscrew the screw and sharpen each blade separately),
Do you thread the scissors before and after sharpening (to set the correct gap between the scissors' blades (checked on a curved ruler),
How much time you spend on sharpening (if up to 20 minutes, then send it back home),
If the master of the above questions does not stand up or goes away from the answer, then, accordingly, there is no reason to talk about fine-tuning the tools. For example, in order to polish nail scissors and iron the cutting edges, it takes from 1 hour to 2-3 hours. This can only be done in stationary conditions with the right lighting. Therefore, sharpen the tool in a specialized workshop or a private master. And remember - "a good master on the road is not lying"! Sooner or later you will find one that suits you.
Who are the master sharpeners?
The correct name for such a profession is a bartender for hairdresser, manicure and pedicure tools. And the name - sharpener hairdressing, manicure and pedicure tools is not entirely correct, and here's why: the "sharpening" and "finishing" operations are different in content. Sharpening involves the initial roughing with allowances for finishing. Finishing - finishing finishing, where you need to maintain exact dimensions, set the surface finish quality of the working edges (includes polishing and smoothing, bringing the cutting edges to razor sharpness and specular gloss).
The fact is that hairdressing, manicure and pedicure tools require high precision processing, setting the cutting edges of the correct shape, otherwise they simply will not work as needed. Therefore, if you turn to a simple locksmith or to a tool sharpener, he will most likely ruin your tool.
What steel are made manicure and pedicure tools?
Usually, tools are made from high-chromium martinsite grade stainless tool steel. Such steel grade as 20Х13 is the most common, cheap hair and nail tools are made from it,
from such steel grades as 30Х13, 40Х13, (rarely 45Х13, 65Х13), make professional manicure and pedicure tools. It is among the masters called "medical steel",
High-quality tools are made of steel 95X18; this is the same “medical steel”, but more expensive.
Tools made of steel 30X13, 40X13, 95X18 must be subjected to heat treatment to increase hardness and wear resistance, and most importantly to increase the corrosion resistance. To do this, use a vacuum furnace to eliminate oxidation and decarburization of the surface layer of the metal.
1 Control of cutting tool heating
The durability of a cutting tool during the cutting process largely depends on the process of cutting. The process of heating and how the cooling takes place is one of the most important during cutting. Currently, tool life is increased by developing new types of hard alloys, new coatings and types of chip breakers.
Heating occurs due to the speed at which the cutting tool hits the metal and due to friction of the discharged chips. When CO2 is applied to the cutting surface, it significantly extends the life of the cutter. Also used channel lubrication system consisting of two substances - for CO2 and dry lubrication in the form of an aerosol or air. During expansion through the coolant supply hole and subsequent evaporation, the carbon dioxide is cooled to –78 °, settling on the cutting tool, the part produced and the white chips formed (sometimes called artificial ice). Therefore, the dual cooling system works very well and quickly.
The use of special chipbreaker on the cutters increases the service life by 20-25%.
The use of internal coolant supply on drills increases the service life by 30-40%.
The use of internal coolant supply on the mills increases the service life by 20-25%.
The use of double CO2 cooling and dry lubrication on the drills increases the service life by 45-60%.
The use of chip breaker on drills increases the service life by 15-20%.
The use of chip breaker on the mills increases the service life by 35-50% depending on the processed material.
Applying a coating on a cutting tool increases durability at least 1.5-2 times.
Now we come to the subjective factors
That is, it depends on you how long very good and professionally sharpened manicure tweezers will work. There are two such factors:
Habit to work with blunt cuticle nippers
In the good old Soviet times, when a manicure was done, especially where there was no good sharpener, the skin of the cuticle was torn off by pieces, and not gently cut off. The client needed a little patience. After all, "beauty requires sacrifice." I am sure that now, in our time, there are such precedents. However, clients in our century have become more picky and such a pseudo-master is doomed to the losses associated with a decrease in clientele. When true professional nail clippers come into your hands for the first time, you experience some euphoria. What a cool tool! How well sharpened! Cut like clockwork! I'm just flying! I work effortlessly! These tweezers make manicure with my eyes closed! And so on. Such a person will work professional manicure tweezers 1-1.5 years or more. But gradually getting used to it. You quickly get used to the good. As one of the sharpeners formulated the idea that good sharpening is like a drug, which, having tried once, you want even more. As a result, the period of work of tweezers until the next sharpening is gradually reduced on average to one to two months. This is only an average. There are masters who work 6 months. And there are especially scrupulous professionals - they buy a dozen tweezers and work every week. And they give to sharpening still quite sharp, but not perfect. These are, of course, exceptions. It’s worth adding that if the sharpener grinds down a tool badly, then he notices that tweezers are worn less often. “So” - thinks, “sharpening lasts longer”. Just such a sharpener is less likely to give up a tool - it's a pity!
The second factor influencing the life of professional and properly sharpened tweezers until the next sharpening:
Compliance with cobbler care rules
- It is necessary to protect the tips from damage in glass, enameled and metal utensils. One day, a client brought me three freshly sharpened nail clippers to reshape me. The tips supposedly tighten. It turned out on all three small, but noticeable to the light bend the tips inward. As it turned out the cause - careless work with a ball sterilizer.
- Lubricate the friction units after sterilization. Many ignore this simple procedure. Medical steel used to make professional tweezers for manicure is conditionally stainless.
- Disinfectant solutions with prolonged exposure can cause oxidation of the internal surfaces of the noccoat joint. Thermal sterilization causes the oil to dry. Work without lubrication significantly accelerates wear, which means that the tweezers will last until the next sharpening.
We hope that the information was useful and will help extend the life of your professional tweezers to regrind. It is also necessary to note that regular sharpening produced on time prolongs the life of the tool as a whole.
Considering the above said, it will be more objective to determine not the time, but the number of manicures made by one tool. You and I will be very interested to know the answer to the following questions:
- How many manicures (pedicures) do they have enough cuticle nippers for different brands?
- What nippers work more reliably and how much?
To answer these questions, we invite and ask all manicurists who work with any nail clippers, tweezers, scissors, to participate in the survey. The survey results are displayed in a comparison chart. The chart is active; when you hover the cursor on a column, the name of the instrument manufacturer will appear and the average statistical number of manicures (and pedicures) made by the tool of this company will be indicated.
2 Cutting and durability
Manufacturers of cutting tools use radial or stepped sharpening (with a regular brush or nylon fiber brush). But the most important thing is to choose the right front and rear corners. The correct value depending on the material being processed significantly increases tool life.
With the wrong rake angle, the cutting forces increase, which is very clearly seen from the spindle load.
With an incorrect back angle, the friction force increases, which is very clearly seen from the load on the spindle.
Moreover, their ratio is a compromise between rigidity and durability of the cutting tool.
If you need a cutting tool for rough cutting with intermittent cutting, it must have a small front and rear corner and a chipbreaker. This implies a large applied cutting force, so when processing thin-walled parts, this tool will vibrate violently.
There are ways to determine the degree of wear of the cutting tool. For example, the easiest way to monitor the level of wear is to monitor the appearance of shiny stripes. When machining steel on the cutting part appear shiny stripes. When machining the cast iron, dark spots appear on the cutting part. In this case, the tool has exhausted its durability.
It is also an interesting way to increase the durability of the cutting tool — this is the first time you use it to reduce the feed rate by a factor of two and a half and so after working it for a couple of minutes. This kind of break-in cutting tool, slightly round the cutting edge, increasing durability by 1-3%. Of course, this is not very much, but it does not require costs and will take quite a lot of time.
3 Tool Design
The design of the tool affects its resistance characteristics. The tooling should give the opportunity to increase the metal removal rate, with an insignificant increase in the load on the spindle. The choice of tools also depends not only on the material being processed, on the accuracy required and on the roughness of the product, but also on the equipment used. For example, when working with an auxiliary spindle, the parameters of stiffness and power are important. When working on a 5-axis machine, a simultaneous multi-directional movement of force exerts on the cutting tool.
At present, the geometry of the tool allows machining with both edges of the plate including additional cutting edges.
An example would be a face mill with identifiable DoveIQMill IQ845 cutting inserts from ISCAR manufacturer. It has a dovetail groove under the cutting plate. This geometric solution completely eliminates vibration, increasing the fixation plate. This double-sided plate has eight cutting edges, four on each side, which greatly increases durability. The main problem in the design of such a tool is to ensure a positive cutting edge angle in the negative profile of the dovetail. As representatives of Iscar say, the result of this work was the “first cutter with identifiable double-sided cutting edges on plates with a large positive rake angle (more than 20 degrees), which ensures smooth and easy milling.”
Another example of an innovative design from the company Tungaloy. DoMiniTurn is a double-sided plate with a positive cutting angle, which uses dovetail geometry.
“The design to which we are all accustomed, the plate with a positive cutting angle is installed in the groove, and in this case only the head of the bolt holds it. DoMiniTurn plates make contact with the groove more rigid and reduces the possibility of plate shift due to the fact that it attaches to the dovetail groove and is screwed down, ”Tungaloy said. According to him, the plate itself has a negative back corner of the non-working edge when installed in a groove. When the plate is turned 180 degrees, the obtuse angle of the back angle becomes the positive back angle.
Each material has different properties during the cutting process:
Cast iron, high-carbon and alloyed tool steels have a significant ability to abrasion, due to the high content of solid iron carbide grains in them. Therefore, the tool operation time when machining such metals will always be lower than when machining low-carbon structural steels.
Stainless steel and iron alloys during the cutting process create molecular wear, and it is very hard to remove heat.
4 Control chips during the cutting process
Chip control during cutting can reduce the risk of tool failure.
Manufacturers of tooling equipment solve the problem of chip removal to increase the resistance in two ways:
coolant to the cutting zone through the tooling.
A striking example is the Walter Sky-tec cutter. It has an axial coolant supply to eliminate radial channels, which eliminates the problem of microcracks in the surface of the cutting tool. Coolant under pressure is directed to the cutting zone, significantly reducing the accumulation of chips, the appearance of large growths and cracks on the cutting part of the tool.
The geometry elements of the cutting tool, twisting the chips into a spiral or crushing it, greatly improve the removal of chips from the cutting edge. The correct choice of these elements increases the durability of the cutting tool by 30-40% depending on the complexity of processing. The wrong choice can even lead to tool breakage, for example, if you use a chip breaker when machining aluminum, the chips quickly stick to the cutting part and if they are not sufficiently washed out with the help of the coolant quickly lead to breakage. Also, the chip breaker design does not allow the temperature from the cutting zone to go from chip to plate, which increases tool life.
Structures are also selected for different types of processing (finishing, semi-rough and roughing) are selected different, to obtain the desired chips and successful its removal. For example, with black processing, the slice thickness is large, so the chips also have a greater thickness, so it does not curl, and it needs to be crushed.
5 Coating cutting tools
All materials emit heat during machining, but heat should not be allowed too much, because the tool and the surface to be machined will be damaged. One of the ways to reduce the increased heating of the instrument is to apply a special coating on the instrument, which reduces friction during cutting.
Types of coatings applied by deposition methods
-chemical (CVD) deposition.
physical (PVD) deposition.
CVD-type coatings are always thicker than PVD, and very well protect the tooling from overheating. PVD coatings are thinner, so they can cover very sharp edges - they have good adhesion at sharp corners, when compared with CVD. Therefore, special laminated coatings have been developed, with the addition of various materials, even aluminum oxide.
Currently, by ion implantation, it is possible to obtain very thin coatings from almost any material, which can significantly increase the durability of the cutting tool, reducing the cost of its use.
In my experience with the cutting tool, the durability value when the tool was chosen was first worked on the cutting mode recommended in the catalogs. Cutters stand up to a certain time and then just break. And they break into parts, often leading to a marriage of the workpiece. After such breaks, the cutters simply have nothing to sharpen. Therefore, the factory made a decision on the forced change after 70% of the spent resistance in the catalog. With this technology, the cutting tool remains intact and at the same time the possibility of refining it, which significantly prolonged its life cycle.
Therefore, in the manufacture of products in single or small-scale production, the cutting mode should be chosen sparing for the tool. Such a choice of cutting modes increases the durability of tooling, and also reduces the scrap rate and improves the stability of the quality of products.