What is a metal milling cutter

Types of metal cutters for a milling machine - classification, features

To be able to process steel workpieces, giving them the desired shape, milling machines are widely used in production. Thanks to metal cutters for milling machines, products are obtained in exact accordance with the engineering design. The types of cutters presented on the domestic market today are very diverse, which allows you to choose the most suitable option for a particular case.

Main types of cutters

Principles of classification of cutters for metal

Different types of milling machines are determined by the design and purpose of the tool, as well as the method of feeding the cutter, among which we can distinguish helical, rotary and linear. The working edges of a cutting tool, each of which is essentially a cutter, are made of particularly hard steel alloys or materials such as ceramics, diamond, carded wire and others.

A variety of cutters makes it possible to select material in the most difficult areas, as a result of which the workpiece is given the required shape and turns it into a specific part.

Many types of cutters in one photo

Classification of cutters is made according to the following parameters:

• location of teeth (incisors);
• design (prefabricated, solid);
• tooth design;
• direction of teeth;
• method of fastening cutting elements;
• material of cutting elements.

Types of cutters for metal

Any novice craftsman faced with the need to process metal has to look for information about what types of cutters are available. Let us describe the most common types of cutters according to their intended purpose.

Disk

Disc cutters are used for the following types of work:

• blank trimmings;
• cutting grooves;
• metal samples;
• chamfering, etc.

The cutting elements of such tools can be located on one or both sides. Depending on the type of processing (from preliminary to finishing), the size of the cutter and its teeth changes. Carbide disc cutters operate in the most difficult conditions with high vibration and the inability to effectively remove chips from the cutting area.

Among the varieties of such tools are:

• grooved;
• slotted;
• cutting;
• designed for processing metal parts on two or three sides.

The names of these tools are determined by their purpose: for example, cutting cutters are needed for cutting metal workpieces on milling machines, and with the help of slotting cutters, grooves and splines are cut.

End

Indexable face milling cutters

Such cutters work with flat and stepped surfaces of metal parts. From the name itself it is clear that the end part of the tool is the working one; accordingly, its axis of rotation is perpendicular to the plane of the part being processed. Most often, such cutters are quite massive, making it convenient to use replaceable inserts. A large number of teeth in the area of ​​contact with the metal part allows for high processing speed and smooth operation of the tool.

Cylindrical

Milling cutters of this type can be either with straight or helical teeth. The first ones process narrow planes, while the second ones work more smoothly and therefore have received universal use.

The axial forces that arise under certain operating conditions of cutters with helical teeth can be very high. In these cases, double tools are used, the teeth of which are located in different directions of inclination. Thanks to this solution, the axial forces arising during the cutting process are balanced.

This type also includes corn-type rasp cutters; they are used to process ledges and cut grooves.

Cylindrical corn cutter in operation

Corner

The edge of such a metal cutter, used for processing inclined surfaces, as well as corner grooves, has a conical surface. There are both single-angled and double-angled types of tools, differing in the location of the cutting edge (in double-angled models they are located on two adjacent conical surfaces, and in single-angled models they are located on one conical surface). With the help of such cutters you can make chip grooves in various types of tools.

Dovetail corner cutter

To form grooves with beveled side surfaces, single-angle dovetail and inverted dovetail metal tools are used.

End

Most often, end (or finger) cutters for metal are used to create grooves, contour ledges and recesses, and process mutually perpendicular planes.

End mills are divided into several varieties based on the following characteristics:

• monolithic or soldered cutting elements;
• with a conical or cylindrical shank;
• for final metal processing (small teeth) or for rough processing (large teeth).

Carbide end mills are used to work with difficult-to-process metals - steel, cast iron, etc.

Among the end mills, there are also spherical (ball) cutters, necessary for processing spherical recesses, radius cutters, used for cutting grooves of various shapes, and mushroom - carbide cutters for T-shaped grooves on workpieces made of cast iron, steel, and non-ferrous metals. End mills also include engraving cutters or engraving cutters that are used for cutting precious metals, copper, brass and other materials.

Shaped

From the name it becomes clear that this type of cutting tool is designed to process shaped surfaces. Such cutters are actively used for processing metal parts with a significant ratio of the length of the workpiece to its width, since the shaped surfaces of short parts in large industries are often produced by the broaching method. Shaped cutters with a backed corner are the most difficult to sharpen.

Based on the type of teeth, shaped milling tools for metal are divided into two types:

• with pointed teeth;
• with backed teeth.

Worm

Processing is carried out using the rolling method due to the point contact of the workpiece with a tool. Hobs are divided into a number of subtypes according to the following parameters:

• solid or prefabricated;
• right or left (direction of turns);
• multi- or single-pass;
• with unpolished or ground teeth.

Annular cutters (or core drills)

Such tools are used to produce holes, and annular cutters provide approximately 4 times higher cutting speeds compared to twist drills.

There are metal cutters not only for CNC machines, but also for drills. Otherwise they are also called burrs. Their design includes a special pin for clamping in the drill chuck. Burrs can be found on sale only in the form of kits, since working with metal using a drill requires precision and cutter shapes appropriate for the specific task.

For a hand router, cutters are also purchased as a set. There are edging tools with and without bearings. The former are used for processing the edges of a part using a manual milling machine, the latter can be used on any part of the workpiece, however, templates are required for more accurate work. On the domestic market, as a rule, you can find Chinese cutting tools for hand routers, but their quality can be assessed as quite high.

At home, you can use a tool such as a drill-cutter to process metal. However, it can only be used for parts of small thickness. Experts do not recommend inserting it into a hand router - it should only be used in an electric drill.

Wide range of milling machine capabilities

It should be noted that modern cutters allow you to work with almost all types of metals and alloys, including steel, cast iron, aluminum, copper and so on. Modern milling machines are distinguished by a good ergonomic design, high safety and the presence of a large number of sensors that monitor engine temperature, cutter rotation speed and other parameters.

The correct choice and timely sharpening of the tool allows you to work with maximum efficiency and high precision, giving the part the required shape.

Source: http://met-all.org/obrabotka/prochie/freza-po-metallu.html

Metal milling cutter: types, types, classification, for metalworking, what they are, their purpose

Metal cutters are a tool whose functional purpose is to cut solid steel to give it the required shape. The work of this tool is carried out by rotational-translational movements. Sometimes the rotation during processing is eccentric (with different conventional centers of rotation), and sometimes it is carried out in several planes at once. The entire load when processing a metal surface is taken on by the equipment.

There are many types of cutters for metal. Let's look at them in more detail in this article.

Principles of classification

For processing metal workpieces, cutters for machine tools are different, depending on the following characteristic features:

• depending on the material from which they are made;
• in the direction of metal processing (there are inclined, screw);
• by type of sharpening;
• depending on the design of the instrument (monolithic, prefabricated or composite);
• according to the location of the cutting edges and the type of their fastening (if composite).

These conditional divisions are necessary so that you can accurately select the type of cutter that would be most convenient for processing a metal workpiece in order to give it the required shape. However, the defining classification of rigs is related to their shape. More on this later.

Kinds

Main types of cutters

Metalworking cutters are classified according to their shape, which depends on the direction of application of force to the cutting edge. The following types are distinguished:

• disk;
• end;
• cylindrical;
• corner;
• end;
• shaped;
• worm;
• ring.

Let's look at all the varieties one by one.

Disk

This type of tool is widely used on profile machines, as well as on automatic longitudinal turning of workpieces. The following types of disk tools are distinguished:

1. grooved
2. Double sided
3. Tripartite.

Using disc cutters, they make slits in the workpiece and also divide it along its length (for cutting). When choosing the appropriate type of equipment, you need to pay attention to the following parameters:

• Diameter. When making slots in a workpiece, the diameter of the cutters is determined depending on the maximum depth of the groove from the surface of the workpiece. When cutting a workpiece, the diameter of the tool is selected according to the depth of the cut.
• Width. It all depends on how wide the groove needs to be cut. It is necessary to minimize the cost of machine hours, as well as tool wear. Based on these considerations, the width is selected that will be optimal for forming the required structural feature of the part being formed.

Disc cutter material. Here they distinguish:

• HSS;
• HSSCo;
• carbide discs.

The principle is simple: metal is processed with a tool made of a harder metal.

Number of teeth on the disc. Depending on what material needs to be processed, the alloy from which the cutter should be made is determined, as well as its required shape (minimum number of teeth). Its cost depends on this.

End

They are used on equipment to form flat and stepped surfaces on workpieces.

Each of its teeth is a standard cutter, with its cutting edges located exclusively in the end surface.

The axis of the cutter is located perpendicular to the workpiece plane being processed.

The main load is carried by the side cutting edges. At the same time, its teeth do not act on the part all together and at once, but one at a time (that is, the emphasis is not made by the entire plane of the tool). This makes it possible to process workpieces evenly.

Face Tool Features:

• the presence of a large number of cutting edges (blades);
• increased rigidity, which also requires rigid fixation of the tool in the machine spindle.

These features allow end mills to provide increased metal processing performance (when compared, for example, with cylindrical ones). However, for face tools it is necessary to select the correct coolant and lubricant. Due to its potentially higher productivity, better cooling and lubrication are needed here to maintain its cutting ability.

Source: https://2lzz.ru/elektroinstrument/frezer/kakie-byvayut-po-metallu

Classification of cutters for metal and their types: description of different types of tools, areas of application - Machine

17.12.2019

This type of cutting tool is available in a wide range. It can be used to carry out various technological operations. The process itself consists of slowly feeding a rapidly rotating cutter into the work area. In terms of the accuracy of processing workpieces, this technique is only slightly worse than external drawing of metal.

A variety of metal cutters allows you to select material in the most difficult areas. The main thing is to determine the required type of tool and the method of feeding it (for example, screw, translational-rotary).

Its cutting edges are made of special grades of steel, ceramics, hard alloys, diamonds and a number of other materials (carded wire, etc.).

Let's look at the main types of metal cutters for a milling machine and their purpose.

Classification of cutters for metal

• According to the location of the cutting parts (teeth).
• According to their sharpening.
• By direction (oblique, helical, etc.).
• According to the design of the tool (monolithic, prefabricated, composite).
• For fastening cutting elements.
• According to their material.

Therefore, it is somewhat difficult to list all the varieties of this instrument, taking into account the specifics of its design and application features.

Types of cutters

Each of them is used only at a certain technological stage of metal processing, depending on the problem that needs to be solved.

Cylindrical

Products with cutting screw parts are more versatile.

But since axial forces can be significant, their use is limited by the angle of inclination of the cutting edge (no more than 450). Therefore, in such situations, dual cylindrical cutters are installed. The peculiarity of their execution is that the cutting parts during operation “cover” the junction of the tool halves.

Varieties:

• Slotted.
• Cut-off.
• Grooved.
• For cutting on two or three sides.

Worm

They have a specific application. The material is processed by rolling.

Feature - metal sampling occurs in the process of point contact of the cutter with the workpiece.

Varieties

• Left or right (depending on the direction of the turns).
• Single or multi-pass.
• Prefabricated or one-piece.
• With teeth ground or unpolished.

End

For processing grooves, ledges and so on.

End mill

End mills are a cylindrical metal-cutting tool with sharp cutting edges located at the end and on the cylindrical surface. The main work is performed by cylindrical cutting edges, the end teeth are mainly used for cleaning the machined surface.

Scope of application

End mills are used for processing planes, grooves and shoulders; they can be installed on a milling machine or in hand-held power tools. This tool is widely used to create contour ledges and recesses, processing surfaces located at right angles to each other.

The cutter can be used for semi-finishing and finishing, depending on the size of the teeth. Tools with large cutting edges are used for semi-finishing, while tools with normal cutting edges are used for finishing. The diameter of the cutters ranges from 2 to 28 mm, length from 7 to 45 mm.  

Features of operation

The accuracy of cutting a groove with an end mill along the width largely depends on the wear of the tool. Also influenced by the rigidity of the machine and the size of the runout after mounting in the chuck. If the nominal size is lost due to wear or regrinding along the cylindrical surface, the diameter size is distorted and accurate cutting of the groove width is impossible.

The solution to the problem is processing in two passes - roughing and finishing. The main metal removal is carried out during black processing; during finishing, the groove is calibrated in width. Chucks with adjustable runout (eccentricity) are also used, which allows you to obtain the exact width of the groove while losing the size of the cutter.  

GOST standards

End mills with a cylindrical shank are regulated by GOST 17025, with a conical shank - by GOST 17026. Tools with carbide inserts are governed by GOST 18372. There are also other standards governing all types of these tools.

Source: https://mekkain.ru/library/freza-konczevaya.html

Metal cutter: features, types, design, principle of operation

The main tool unit used on modern metalworking machines is a milling cutter, which has advanced capabilities for processing workpieces of arbitrary shape. Thanks to this universal tool, it is possible to obtain a cut of any degree of complexity, prepared in accordance with the requirements of the technical specifications. There are many cutters for metals on the Russian market, which makes it easy to choose the best option.

The purpose of most milling tool samples is determined by their type. Thus, end mills are, in particular, used in the following production areas:

• In the automotive industry (when processing gearbox housings, for example).
• In the manufacture of equipment used in the oil and gas industry, as well as fittings for pipelines and other types of main communications.
• In the production of special tools, equipment and other structural forms.

They are also in demand in the production of workpieces that are part of complex equipment in such industries as general mechanical engineering, energy and construction.

It is also difficult to do without milling operations in such important industries as shipbuilding and the manufacture of medical devices.

Design and operating principle

The main requirements for a tool of this class are strict adherence to the parameters stated in the technical specifications or specifications. This will require high-precision machining of the cutter elements, which can only be achieved using an end tool with a large set of teeth. High sample purity (up to a micron) is ensured by special adjustable cutting inserts.

Features of their design include the presence of working edges, which are a separate carbide cutter.

Important! In the manufacture of inserts, heavy-duty materials such as diamonds, ceramics, as well as special carded wire and the like are used.

A large assortment of milling tools, differing in design details, allows you to select a sample suitable for certain processing conditions. Let us add that according to its design it is usually divided into one-piece and collapsible.

The principle of operation is to accurately select metal from the most difficult areas of the workpiece being processed, which allows it to be given the desired shape. After this, the original blank is transformed into a product or part suitable for further processing.

Classification

Known types of milling equipment can be classified according to the following characteristic features:

• The order of arrangement of individual teeth (incisors).
• The type of execution determined by its design.
• The method of attaching cutting attachments, as well as the material used in their manufacture.

Based on the totality of the considered characteristics, tools of this class are divided into worm, cylindrical and end tools. In addition, they can be either cut-off or disc-shaped; Moreover, this enumeration does not exhaust the set of possible types.

Let's look at each of these varieties in more detail.

The products indicated in the title of the section refer to the main types of equipment that are in demand when processing particularly complex parts and workpieces. They suggest two designs, differing in the shape of their teeth (the latter are either straight or helical). Each of these modifications should also be considered separately.

Straight teeth

Tools that use straight teeth as cutting parts are in demand when processing well-accessible areas within the workpiece, located parallel to the line of equipment placement. This type is extremely rare. Most often, preference is given to samples with helical teeth, which are characterized by greater functionality.

With helical teeth

The teeth of this type of equipment are located along a helical line having a given angle of inclination. This tool is more suitable for sampling material in narrow areas of the original workpieces.

To reduce the magnitude of axial loads, cutters are suitable whose teeth are selected at different angles of inclination of the working edges.

Face

Face tools are widely used along with cylindrical modifications. Their characteristic feature is a vertically oriented axis of rotation, which determines their scope of application. Such equipment is mainly in demand when processing extended flat surfaces from which a layer of material of a given thickness is removed.

One of the typical representatives of this type is the so-called “corn”, which in appearance is very reminiscent of the southern vegetable of the same name.

Single and multi-pass

Compared to samples with only one pass, multi-pass tools are more productive. On the other hand, as the number of passes increases, the accuracy decreases, which forces this type to be used only for roughing.

Such cutters provide high accuracy of the cutting step, since several passes are made over the same place.

Grinding and non-grinding teeth

Products with a high class of processing (both single- and multi-pass) are used for grinding cut surfaces. All other types of tools that do not have the required accuracy can be classified as the second type.

Solid and prefabricated cutters

The first of these modifications is presented in the form of a solid blank made from a monolith of tool material. While composite milling equipment is made of two parts. One of them is a cutting one (made of heavy-duty material), to which a shank made of structural steel is welded.

Double sided

A special feature of the double-sided disc modification is the double arrangement of rows of teeth. In addition to the cutting elements located on the end part, it has cutters placed directly on the surface.

Tripartite

With a three-sided tool (as opposed to a two-sided version), the cutting teeth are located in three places at once. They are placed at each of the ends, as well as on the surface of the tool base.

Grooved

This type of tool has teeth located only on the working surface. They are mainly used when making not very deep grooves. One of the modifications of this instrument is called a dovetail.

End and corner

End mills are in demand when it is necessary to mill workpieces not only on machine tools, but also using hand tools. The peculiarity of the end modifications is as follows:

1. They are made together with the leash in the form of a shank of the selected shape.
2. They do not require additional equipment.

By design, they can be all-metal or with cutting inserts.

A distinctive feature of angle cutters is that the cutting edges at the end are inclined. They are very convenient for removing rectangular chamfers, as well as for working with inclined surfaces and corner grooves.

Monolithic

All-metal end milling fixtures are typically made from structural steel. They are equipped with ring grooves that remove material, wound in a spiral in one direction or another.

With soldered crowns

Milling cutters with soldered inserts are, in turn, subdivided according to the type of tip made of carbide teeth, which can have many different designs. One of the most common is the crown tip.

For pre-treatment

Separately, end and corner tools are distinguished, which are in demand during preliminary milling of material. They, as a rule, do not differ in the precision of processing, which is realized by finishing milling cutters.

Source: https://VseOChpu.ru/freza-po-metallu/

Features of choosing a cutter for metal

Milling is a process in which the part moves forward. A metal cutter has several cutting edges and allows you to process a workpiece along a plane at high speed, clean the ends and make grooves. Depending on the shape of the working surface, beveled and curly edges are obtained.

Special cutters for drills and routers will allow you to make necessary things or simply beautiful crafts in your home workshop. Craftsmen independently make an instrument with an original configuration from scrap materials.

Design and principle of operation of the tool

Of all types of metal working tools, cutters represent the largest and most diverse group. Their design and operating principle differs from all other cutters and drills. The tool mounted on the spindle rotates. The part moves relative to it translationally along three axes and at an angle in any direction. Sharp edges and blades remove chips. As a result, on the workpiece:

• planes are processed;
• the ends are cleaned and shaped;
• keyways are cut;
• slits are made;
• rolled parts and parts are cut off;
• chamfers are removed;
• teeth and splines are cut;
• T-shaped and figured grooves are made;
• holes are drilled and bored.

The cutter is a multi-cutting tool and consists of a body on which the cutting edges are located. There is a conical or cylindrical shank for mounting into the chuck. The part is fastened to the mandrel with washers, sliding the groove onto the protrusion for rotation. It can have insert plates and cutting edges sharpened from a single piece for metal milling.

Popular varieties

Several types of metal cutters are used in production. They are divided into groups depending on the shape, location and type of cutting edges and the operations they perform. A separate group is represented by varieties of metal cutters for drills and hand routers. They are small in size, with a cylindrical shank with a diameter of 6–12 mm, depending on the drill chuck. Otherwise, they are completely similar to the tools used in production.

T-slot cutter

For fastening parts on machine tables there are T-shaped grooves, turned wide side down. The heads of the pins are easily inserted into them to secure the workpiece.

The grooves are cut with a cutter of a figured configuration. Cutting edges of different diameters are located on one mandrel - from the end there is a wide and low cylinder, and closer to the mandrel there is a thin one. Milling in 2 passes is possible. First, to the full depth with a finger or cylindrical narrow cutter, then milling with a wide tool along the bottom of the groove.

Keyed

To create keyways, special finger-type disc cutters with a cutting end are used. The tool is first lowered to a predetermined depth, working like a drill. Then the sampling is carried out vertically - milling.

To make keyway and other grooves with a router, a template and a copy sleeve are used. The stencil can be made from any material, including plywood, plexiglass, and wood. Its dimensions are larger than the cut-out understatement by the difference in the diameters of the copy ring and the cutting tool. The sleeve slides along the edge of the template, preventing the router from deviating to the side. You can cut out any shapes, including ornaments and inscriptions.

Shaped

Shaped cutters have many cutting edges and resemble a rough shaped file with a shank for mounting in a chuck. They are used to give the end a certain complex configuration. The edge shape is the opposite of the tool.

Manufacturers and rules for choosing equipment

The choice of cutter is made based on several factors:

• equipment:
• type of mining;
• material.

The quality of the tool is determined by the manufacturer. For example, the best sets of metal cutters for hand routers are produced by BOSCH. The cost of such equipment is slightly higher than that of other European companies, but the quality and service life are high. A special feature of German tools is the manufacture of a shank chambered for a specific model of electric tool produced by the company. It may not match the chucks on other routers.

The products of the following companies are of good quality:

Domestic products are durable due to traditions in the production of high-quality alloys. You should pay attention to the cutting tools of companies:

• Tool-Service;
• Corvette;
• Globe.

Domestic cutters are cheaper than imported ones. Their disadvantage is a small selection of sizes and shapes.

Required number of teeth

When choosing a circular saw, you should take into account that the smaller the tooth, the cleaner the processing. A fast cut is obtained with a large tooth and a feed of 50%.

Face milling cutters are selected according to the hardness of the material. You can machine cast iron using a set with 4 cutting edges at high feed and high speed.

For fast roughing, choose a tool with a large number of inserts. Feed depends on the composition of the steel and its hardness.

How to choose material

To work with metal, you should choose plates that can cut metal for a long time and not wrinkle. They must be significantly harder than the material being processed. You should take hard heat-resistant alloys. The shape of the plate and its size are selected according to the body and method of fastening.

For a router, the set of tools for working with metal is limited. Aluminum, copper and their alloys can be milled with wood tools. For cast iron and steel, you should choose double-flute carbide cutters. The wood tool has a cutting edge that is soft for metal and a sharper sharpening angle.

Storage and operation rules

Before starting work, you need to select and place next to the workplace all the cutters that are used to process parts. You need to allocate a special bedside table or shelving unit for them. After work, the entire tool should be cleaned of dirt, checked for edge wear, and lubricated with oil or grease to protect it from moisture. It must be stored on special racks.

Cutters and drill bits for drills and routers are placed vertically in special boxes, with the shank down.

Milling is carried out with a tool appropriate for this operation. Rough milling of holes should be done with a drill. A finishing disc cutter and countersink are used when the allowance per side is several tens.

Making a cutter with your own hands

Metal cutters must be harder than the material being processed. For self-production use:

• drill;
• circular saws;
• hacksaw blade.

By regrinding the drill, you can get a cylindrical, end and key cutter for the router.

For cutting circular saws, the body is made of tool steel St U8, and similar ones. From them you can cut out elements with a tooth, assemble them onto a mandrel and get a cutter for longitudinal grooves.

The figured miter cut should be made from a circular saw or hacksaw blade.
The mandrel is machined from a round rod. Holes are drilled into it from the end and sides to guide and limit the cutting of the groove with an abrasive wheel. A symmetrical blade is cut from a hacksaw blade, inserted into a mandrel, and tightened with a nut on top. The result is a two-flute figured cutter. DIY ball cutter

Source: https://metalloy.ru/obrabotka/frezerovka/po-metallu

Metal cutter: device, types, principle of operation of disk and cutting equipment

A milling cutter is a type of cutting tool. It is made in the shape of a pancake, and there are teeth on its end part. It is used to create grooves of a certain thickness and depth, as well as for sawing workpieces made of steel alloys and ferrous metals.

The metal is processed thanks to many blades that are located on the toothed body of the cutter. As the tool rotates, milling occurs, during which several teeth simultaneously contact the material, cutting layers of varying thickness.

Working teeth are made from hard metals, high-speed steel, carded wire or mineral ceramics. In some cases, the cutter is made with diamond coating.

Depending on the type of teeth and equipment design, the following types of cutters are distinguished:

1. Welded.
2. Whole.
3. Prefabricated.

The one-piece device consists of a single metal. Their main parts are the working section (for end ones) or a disk-shaped body (for attachment ones) and the shank body.

The attachment type includes cutting and disk tools. They, in turn, can be welded or solid. For welded tools, the shank and working part are made of different metals and are attached to each other by welding.

Prefabricated equipment is also made from several metals (most often two), but they are not tightly attached to each other. Their parts are fixed using bolts, screws or wedges. The main part of prefabricated cutters is the body, but the cutters can be sharpened or replaced. Cutters are most often made with carbide tips or high-speed steel.

Disc cutter

This type of equipment is one of the most productive; it is used for making ledges, cutting off workpieces, making various recesses, grooves and grooves. Their teeth at the ends have additional working edges, the diameter of which greatly exceeds the length of the tool itself.

This type of cutter was created to work with metal in more difficult conditions, with clamping and vibration. Vibration may be associated with low rigidity of the equipment body or poor chip removal from the working area.

The metal disc cutter is divided into the following types:

1. Slotted.
2. Three-way.
3. Grooved.
4. Double sided.

Slotted disc cutters have cutting teeth only on the outer cylindrical surface. They are very convenient for milling small grooves. Double-sided ones have both surface and end teeth. In three-sided equipment, teeth cover the surfaces and two ends; with their help, you can simultaneously process several perpendicular planes in ledges or grooves.

In order to make grooves and narrow grooves on workpieces , they use thin disk tools, they are also called “saws”. The chamfers at their ends are sharpened one by one. Basically, 50% of the working edge is removed by chamfering.

It is for this reason that the layer of metal that is cut by the teeth is less than the width of the future groove. This design of the equipment provides spaces between the teeth for chips, which are therefore easier to remove.

If the width of the cut is the same as that of the groove, the chips will catch on the walls and get stuck, which can cause breakage of the cutting surface.

Cut-off cutters

A cutting cutter is a type of disk cutter. They are created for dividing a whole workpiece into parts and cutting off fragments of blanks. There are no working sharp edges at the ends, since they are located around the periphery. Based on the size of the teeth, the following types of cutting cutters are distinguished:

1. With big teeth.
2. With the little ones.
3. With average (normal).

Many cutting cutters are class “B” in accuracy and have a thickness of more than 1 mm. Tools with medium and small teeth are used for milling cast iron and steel, and tools with large teeth are used for light and soft metals.

Choosing the right tool for yourself is not difficult; you just need to know the characteristics and parameters of the equipment. Such parameters include the number of teeth and the material from which the product is made. The key to choosing a product material is the strength of the metal you are going to cut.

Storage and testing rules

Testing of disc cutters for performance and durability takes place on samples made of steel 45, with a cutting speed of 20-100 meters per minute. Tests are carried out on milling machines using a special mandrel and dressing rings. The total milling length of each tool that is subjected to metal testing is 25−50 cm.

Test treatment is carried out with the obligatory supply of coolant and an aqueous emulsol solution. After the test is completed, there should be no staining phenomena on the cutting parts of the cutting disc cutters. If after testing the cutter is ready for further use, it is considered to have passed the performance test.

The appearance of the equipment is analyzed visually, according to GOST. The inspection is carried out using a magnifying glass with fourfold magnification. Hardness is tested according to standard 9013, and roughness - 9378.

The equipment is made of high-speed alloys , which include high-alloy steel grades with increased heat resistance. A similar distinctive feature is achieved by introducing molybdenum, chromium and vanadium into the alloy in combination with tungsten. For the production of cutting cutters, the following grades of steel are mainly used: R6M5, R12, R18.

Alloys are supplied to factories for the manufacture of cutting tools in the form of steel blanks (forgings).

When cutters are subjected to heat for hardening , austenite begins to form in the alloy. It contains a relatively small amount of carbon and is heavily doped. The cutting tool receives a special structure after hardening and consists of martensite with small needles, various carbides and retained austenite.

The main alloying additives for high-speed steels are vanadium, tungsten, molybdenum and cobalt. It is these elements that can provide the required red resistance of the material. Chromium must be added to such alloys. Particular attention is paid to the amount of carbon in the steel: its number must be such that carbides of the introduced additives can form in the alloy. If the amount of carbon is less than 0.7%, then the finished cutter will not have the required hardness.

How do alloying elements affect the properties of alloys:

1. Phosphorus and sulfur have a negative impact on the characteristics of high-speed steel compositions. In the alloy, their amount should not exceed 0.03 and 0.015%, respectively.
2. Tungsten and molybdenum are the main alloying additives. It is thanks to them that a high degree of operational and red-hardness of steel is ensured.
3. The alloy should contain no more than 4% chromium. It imparts increased hardenability to the metal.
4. Cobalt increases red resistance, but removes carbon from the steel and reduces its strength and toughness.

Most often, the tool is made of steel grade R6M5. Its cost is lower, but the cutter is also less wear-resistant than materials made from the P18 and P12 brands.

The P18 alloy has maximum wear resistance: it contains the largest amount of tungsten, hence the high cost. And in terms of heat resistance, the best tool is considered to be one made of P12 steel.

Methods for increasing wear resistance

High performance characteristics are guaranteed by high-quality heat treatment of the equipment. The cutter can be subjected to various hardening options, which increase their wear resistance. Hardening is performed using the following methods:

1. Light. This is a type of thermal step processing. To implement this, it is necessary to cool the steel with special compounds. Basically, a mixture of molten alkali and water is used for these purposes.
2. Intermittent. This technology is popular because it eliminates the risk of cracks appearing in finished products.
3. Continuous. This type of hardening is rarely used, since it is performed with accelerated cooling. And such manipulations often cause cracks to appear on the device.
4. Stepped. This type of hardening involves cooling the workpieces in a hot atmosphere (up to 600 degrees), and then in the open air.
5. Very rarely, isothermal partial or complete hardening, as well as induction heating, can be used.

During heat treatment, heating is carried out:

1. In special salt baths.
2. In gas and electric units in a protective environment.
3. High frequency currents.

Milling cutters are necessary for processing metal products and cutting grooves and other holes in them, which is why choose it correctly. Consider all the nuances of the subsequent processing process and the type of metal you are going to work with.

Source: https://tokar.guru/stanki-i-oborudovanie/frezy/freza-po-metallu-princip-raboty-vidy-i-vybor-instrumenta.html

Milling cutter. Types and work. Application and resource. Peculiarities

A cutter is a cutting tool that has one or more teeth. Depending on the design features and the rigidity of the material from which the cutting edge is made, cutters are used for processing metals, plastics and wood. The tool is fixed in machines that ensure its rapid rotation, which is necessary for processing workpieces.

Metal cutter

Metal cutters are used for processing steel, cast iron, aluminum and other workpieces. They are made from high-speed steel. Such cutters are made solid or prefabricated.

According to the design features, the tool is of the following types:

• Disk.
• Tortsevoy.
• Cylindrical.
• Angular.
• Terminal.
• Shaped.
• Worm.
• Annular.

Disk

A disk cutter is used for cutting workpieces, as well as preparing grooves in them. With its help, you can select metal or chamfer. Externally, such a tool resembles a regular saw blade, which can be found on a circular saw.

The only difference is the smaller diameter and greater thickness. Also, the teeth of the milling disk are placed at a different angle. The quality of processing depends on the size of the teeth. The larger they are, the rougher the work. At the same time, high, sparse teeth ensure rapid metal removal.

They also remove chips more efficiently, which reduces overheating.

End

End mills are used for processing flat surfaces on which you need to create a stepped transition or recess. The working part of the tool is its end. According to the principle of operation, such a cutter is equivalent to a regular drill, but has a larger diameter. Typically, such tools have 6 cutting teeth, which ensures faster penetration into the metal. Special grooves remove chips. The end surface allows you to create a recess with a flat bottom.

Cylindrical

Cylindrical cutters are similar to disc cutters, except that they are significantly wider. Their teeth can be straight or helical. Straight edge dies are used for working on narrow surfaces.

Helical teeth are more versatile and can often handle harder metals. The tooth angle usually does not exceed 45 degrees, as this minimizes runout on the shaft.

Often, the cylindrical design provides for the connection of several attachments on the machine shaft, which is necessary when processing wider workpieces.

Corner

The corner type is designed for cutting into metal and creating inclined surfaces. With its help, you can form a sample like a dovetail. This tool allows you to make circles, as well as shaped and longitudinal grooves on various metal surfaces.

The wide part of the cutting edge can be either at the bottom or at the top, which allows you to form the desired direction of the cutting angle in the workpiece. The actual level of inclination of the cutting edge and its height are different and are selected depending on what kind of workpiece needs to be obtained.

End

An end mill is also called a finger end mill. It is a long drill with about 5 cutting edges. With their help, a deep groove is created. Usually such a tool is monolithic, but there are soldered edges. This design allows for easy and fast work on hard metals such as steel and cast iron. The resulting recess has a flat shape. If it must be rounded, a spherical design of end mills is used.

Shaped

Such cutters are used for processing shaped surfaces. A long workpiece is pulled through such a tool. As a result of contact, its side part is removed and adjusted to the required parameters. This tool is one of the most difficult to produce, as it requires special equipment for sharpening. Restoring a cutting edge at home is quite difficult, but it is doable with the proper experience and some equipment.

Worm

Hobs are the widest. They allow sampling from the surface with a large coverage. This tool is one of the most expensive because it has quite large dimensions. Its teeth can number several dozen or more. According to the direction of the turns, such nozzles can be left-handed or right-handed.

Ring

Most people are familiar with annular cutters as core drills. They are designed for drilling sheet metal. Externally, their design resembles a tube with teeth that cuts into the surface, creating a hollow ring. The diameter of the ring may vary significantly. For precise positioning, there is an ordinary drill in the center of the crown, which first cuts into the surface and ensures centering.

Wood cutter

Milling cutters are also used for processing wood. Due to the fact that this material is softer, the cutting tools for planing are smaller in size and cost. It is also more high-speed. Such attachments are installed in hand-held milling cutters or stationary machines.

The cutters used on woodworking machines are almost identical in appearance to those used for metal processing. The only exception is that they are made of lower quality steel and also have a different sharpening angle.

Attachments for machines are made of the following types:

• End
• Shaped.
• Cylindrical.
• Angular.
• Disk.
• End.
• Keyed.

Externally, cutters for woodworking machines are completely identical to those used for cutting metals. The only exception is key cutters, which are not used in metalworking. They belong to the category of two toothed cutters, with the help of which connecting grooves are made.

Due to the increasing popularity of hand routers, the range of end mills that are installed in them has increased significantly. They differ not only in their cutting edge features, but also in the diameter of the shank. It can be a rod 6, 8 or 12 mm thick.

The following types of cutters are used for a manual router:

• Edges.
• Finger.
• To create connections.
• Special.

The group of edge cutters is an almost identical design with end attachments used for metal processing.

They allow you to give the edges of the workpiece a shaped profile. Their leg has a bearing that stops the attachment upon contact with the workpiece, therefore limiting the penetration into the wood. This category has a wide variety of profile shapes and is often used to decorate countertops.

With their help, you can make figured cuts, trims and create complex chamfers.

A group of finger cutters are very similar in appearance to end cutters, which are used in metal processing. With their help, you can select lugs and create blind grooves. Side edges provide greater processing height. Such a tool is often monolithic. Its shape can be either straight or beveled in the form of a trapezoid or wedge. This attachment effectively removes chips and therefore has a high operating speed.

A cutter for carpentry joints is usually a collapsible structure with many cutting elements. They are used to finish the ends of boards to create grooves for joinery joints. It is these cutters that create a comb for gluing long boards from short pieces.

Special cutters are a combined type that allows you to create a shaped surface at the ends. This category includes tools that can be used to turn the edge of a board into a locking part used on lining or laminate.

How to extend the life of cutters

In order for the cutter to last longer, it is important to first ensure that it is securely fastened in the machine. The appearance of runout at high speeds will lead to the fact that the cutting edge may break off and the attachment will become unusable. To avoid this, you need to not only tighten it securely before working, but also periodically stop to double-check its fixation, since it may simply loosen.

The next important rule is the correct selection of cutters. Do not use a tool whose hardness is almost identical to the hardness of the workpiece. If you ignore this and start working, then the intensity of abrasion will be the same, so the cutting edge will quickly shrink, and its metal will release from overheating.

The next rule is the correct choice of speed. The optimal rotation speed is usually indicated on the packaging of the cutter. If you accelerate it further, it may overheat or a piece of tooth may break off.

We must not forget that during operation the metal becomes very hot. To prevent overheating, it is important to stop the machine in a timely manner to cool down. It is also worth using a lubricant, especially if metal is being processed.

After each treatment, it is worth cleaning the cutter from chips adhering to it. Often the tool is made of steel, which is susceptible to corrosion. Therefore, it is important to ensure that it is stored in an airtight box, isolated from humid air.

If the cutter has lost its sharpness, it should not be used, since a dull cutting edge leads to rapid overheating, as a result of which the tool may deteriorate and then no sharpening will help. There is also no need to create strong pressure on the workpiece, since this also contributes to overheating.

Related topics:

Source: https://tehpribory.ru/glavnaia/instrumenty/freza.html

Milling cutters for a metal milling machine: what are they, types, price

Metal cutters are used for high-performance rough grinding of workpieces and finishing with high precision and surface cleanliness. A multi-blade tool is classified according to several parameters. Its shape depends on the technological operation it performs.

Basic principles of tool classification

Milling cutters are multi-edged cutting tools that process parts while rotating around their axis. A large number of different operations are performed on milling machines. There is a different tool for each type.

Milling cutters are classified according to several criteria:

• size – diameter;
• number of blades;
• cutting edge material;
• direction;
• sharpening;
• design;
• plate fastening;
• shape of cutting edges.

Regardless of the design, the tool has a working part, a shank that is fixed in a spindle or collet, and a neck - a narrowed section between them.

Material of manufacture

The cutting edges of cutters are made of tool steels:

• carbonaceous;
• alloyed;
• high-speed.

Processing workpieces made of annealed and normalized steels - soft and medium hardness, use a tool with a working part made of metal grades U12A, 9ХС, ХГ, ХВГ and ХВ5. Low feed operating mode. For processing at accelerated feed, cutters from St P18 are used or replaced with less wear-resistant ones from St P9.

High-alloy, heat-resistant and stainless steels are processed with cutters made from high-speed steels R9K10 - the main alloying element is cobalt and R18F2 with the addition of vanadium.

After hardening, finishing surface treatment is carried out using prefabricated cutters with plates:

• metal-ceramic;
• mineral ceramic.

The plates are marked tungsten VK6, VK8, titanium tungsten TK10, T30K6.

Reference! The cutting edges are made of hard alloys with high wear resistance. Milling cutter shanks are made of ductile metal with high resistance to torsion and impact: St 45, St 40X, tool U8, U10.

Processing direction

The direction of rotation of the cutter during processing is set:

• right – clockwise;
• left.

It is determined by sharpening the cutter and positioning the cutting edge.

Reference! If the cutter marking does not indicate the direction, then this is a standard tool with right-hand working rotation.

Type of sharpening

When sharpening, a layer of hard metal is removed, the sharpness of the cutting edge and the cutting angle k are restored. The thickness of the removal is determined by the chips, notches, and burrs formed during operation. They must go away completely. Most types of cutters have a long cutting edge line. It is necessary to maintain the configuration and size along the entire length. Manual sharpening of the tool is not possible.

Depending on the shape of the tooth, sharpening is done in different ways:

• along the front surface;
• backing;
• contour.

Teeth are sharpened along the front surface with an edge perpendicular to the contour - the cavity, in which the angle ɣ is equal to 0. An inclined tooth with an angle ɣ ˃ 0 is sharpened along the back surface.

Reference! When backing the tool, the diameter of the cutter decreases.

Shaped, face and other tools for processing simultaneously in 2 or more planes, have several lines of cutting edges. They are sharpened along the contour. The accuracy of the contour is guaranteed by the use of a template or the use of CNC sharpening equipment or a special program.

Important!

Some cutters designed for deep milling and creating complex configurations are sharpened along a contour or front surface with a backing. This ensures free chip removal.

Design

The design of the tool depends on its size and type:

• solid - monolithic;
• prefabricated - typesetting;
• compound.

Solid ones are made from one piece of tool steel. These include small-sized tools for processing medium-hard metal. Prefabricated cutters have an alloy steel body and a shank with a cone welded to it. The tooth is attached mechanically. With compound cutters, the cutting inserts are inserted into slots and welded or brazed to the body.

Location of cutting edges

The location of the cutting edges depends on the purpose and configuration of the tool:

• lateral;
• lower;
• figured;
• combined.

For plane milling, parting and grooving, it is enough to have one edge. Cutting straight and shaped grooves, teeth and other complex elements is carried out simultaneously on several surfaces.

What are they?

A metal milling machine is a universal equipment that performs a large number of different operations.

Corner

The cutting edges of corner cutters are a truncated cone with a wide base and apex towards the shank. Used for chamfering and edge processing. The cutting edge is located on the side surface. They can be solid or prefabricated.

Ring

Hollow cutters of cylindrical shape with sharpening at the end and threads of spiral cutting edges. They have a second name - core drills.

For T-shaped notches

Milling of through T-shaped grooves and recesses is carried out using a prefabricated cutter with 2 cylindrical surfaces. The cutting edges are located on the sides and ends of the lower wide part of the tool. The radius of the cutter corresponds to the width of the groove.

Reference! If there is no cutter of the required configuration, the groove is made in several passes. First, the narrow part is cut to its full depth, and a wide base is selected.

Conical

Conical cutters can be solid or stacked. The angle of inclination of the cutting edge is positive with the apex of the cone towards the shank, negative when directed in the opposite direction.

Spherical

Disc cutters with a spherical edge are used to create semicircular grooves. They are made in one piece or in parts with sharpening along the contour.

How to choose the right type?

Milling cutters are selected depending on the technological operation to be performed:

• rough roughing of the workpiece – end-type and end roughing;
• finishing on a plane – cylindrical;
• creation of grooves – disk, end;
• processing of corners and edges - angular, figured;
• selection of keyways – keyway;
• cutting through grooves – T-shaped, angular, figured.

The main characteristic of a tool is its size and tolerance.

Features of choice for CNC machines

Pre-processing and finishing of parts is carried out on CNC machines. The tool is used with a conical shank, type:

• cylindrical;
• keyed;
• disk;
• end;
• curly.

The cutters must be changed quickly and positioned in the spindle with great precision. Metal cutters vary in size, from tools with a cross-section of 2–3 mm, to huge special structures with 600–800 mm in diameter.

They are presented in a large number of types and allow the production of parts of complex shapes. It is necessary to choose the right tool to create an element of the desired configuration and size.

Source: https://vseostankah.com/po-metallu/frezy-dlya-frezernogo-stanka.html