Among domestic locksmiths, there is an opinion that for the manufacture of any metal part It is enough to give it an approximate outline - the rest can be finalized with a file. Together with a hammer and pliers, this hand tool is one of the three most popular assistants for any homemade product.

With their help you can perform a wide variety of work on metal and other materials:

• Removal of dirt, corrosion and various coatings;
• Surface sanding, from rough to finish
• Giving the required shape to the product;
• Removing burrs and flash;
• Cleaning contacts, preparing for painting;
• Sharpening cutting and sawing tools.

The operating principle is very simple. Using notches on the surface (teeth), a small layer of the processed material is removed. The depth of processing is regulated by pressing force, number of movements and speed.

The industry produces countless files and needle files intended for the most various works and materials, we will help you understand the types of tools.

Types of files and their purpose

As with any other instrument, there are differences in design, material and application.

Teeth size

The most common classification of files is based on the density of cutting teeth.

No. 1 – large notch from 5 to 13 teeth per 1 cm.

The tool is intended for rough, rough processing. If the material is sufficiently soft, you can confidently cut off a thick layer in several passes. With blanks from hard alloys work is difficult. The series is called “bastard files”.

No. 2 – medium notch from 14 to 25 teeth per 1 cm.

The most common and most universal look tool. In classical processing, this file is used after the brute file to smooth the surface. In reality, most often work is performed only by this number.

Any material can be sanded. Soft metal or wood quickly clogs the pores between the notches and requires cleaning wire brush. The series is called “personal files”.

Grinding metal products is not always done with the help of craftsmen. Often, for such work, craftsmen use various types of files. They are much safer than electrical equipment. The worker can choose from a wide variety of tools the one that suits the material being processed. It’s not difficult to cope with this if you know the intricacies of the work, all types of files and their purpose.

Special files are used for processing corners, inclined and jagged surfaces. This type of tool produces narrow grooves and grooves. Brushing tools are equipped with the largest teeth and are intended for initial surface treatment, as they allow you to quickly remove a large layer (0.05-0.1 mm) from it. At the same time, these files have low accuracy. As a result, the working surface is processed roughly. Personal files are used for finishing filing. In this case, a layer 0.02-0.06 mm thick is removed. Velvet ones are used in the final grinding phase. Most of the material is removed from the surface of the sawn product. thin layer(0.01-0.03 mm). These files have high processing accuracy, which is 0.01-0.005 mm.

Rasp

In addition to metalworking files, rasps, which are distinguished by their notches, are used for processing metal and other surfaces. Their teeth are large and shaped like pyramids, behind which there are special grooves. The section on this tool is placed in rows, perpendicular to the axis. Rasps are used during processing soft materials: aluminum and duralumin. Manufactured from steel grades U7A, U10A. Their hardness is 35-40 HRC. Standard length tools: from 25 to 35 cm. Rasps come in four types: blunt-nosed flat, pointed-nosed flat, round, semicircular. The scope of application of the tool is medicine and the production of tin products.

Files

Needle files are the smallest files. Designed to perform very precise work. For the production of these tools, steel grades U12 and U12A with a hardness of 54-60 HRC are used. Depending on the cross-sectional shape, needle files are:

• flat (blunt-nosed and pointed-nosed);
• square;
• triangular;
• round and semicircular;
• oval;
• diamond shaped;
• groove and hacksaw.

It is not necessary for a home craftsman to have all types of files. It is enough to have three main ones - flat, triangular and round. It is also advisable to have a set of needle files and several rasps. With these tools, you can easily cope with any task related to metal grinding.

Despite the abundance electric tool, which replaced the manual one, there are types that have not undergone any major changes over many hundreds of years of operation and are still used to produce many technological operations. One such tool is a file.

The number of their types is difficult to count, and even more difficult to count the number of operations that can be performed with its help.

What is a file and what is it for?

A tool designed to remove a layer of metal from a workpiece is called a file. It is a metal strip on which a so-called notch is applied. It consists of cutting teeth made according to certain rules described in GOST 1465-80.

To control it, use a handle mounted on a specially formed shank. Several grades of steel are used for manufacturing. As a rule, this is steel containing 1.1 - 1.25% carbon. The steel grade can be ШХ15 or У10А, the latter steel is classified as unalloyed improved.

One of the main requirements for it is high hardness. That is why after heat treatment it is not tempered. In working condition, the surface has a hardness of 54-58 HRC.

The handle with which the control is performed can be wooden, plastic, or metal.

They are produced different shapes, length and with different parameters of cutting teeth.

It should be noted that the abundance of this product allows you to perform many types of work, in particular, it can be used to remove dirt different types, grind the workpiece planes, remove burrs and sprues. Using these products of special shapes, it is possible to sharpen saw chains and process gears.

It should be noted that it can be found in almost any home, garage and of course in production.

Classification of files by section shape

The parts processed with it can have different shapes. These can be sheets, profiles, etc. That is why, for productive work, manufacturers produce products of different shapes and geometric sizes. One of the classification options is by section shape. Manufacturers market products of the following types:

• flat;
• square;
• round;
• triangular;
• special;
• oval and some others.

In addition to the fact that products are distinguished by cross-sectional shape, they have different lengths and shapes. The minimum length is 50, maximum 500 mm. By the way, only the part on which the working teeth are applied is measured.

There is some relationship between the length of the working part and the size of the teeth. The longer the tool, the larger the size cutting tooth. Large is used when there is a need to remove a large number of metal But, after processing the material with a tool with big teeth the surface turns out to be rough, scratched, and there is no need to talk about the accuracy of the processing. In cases where it is necessary to obtain a higher quality surface, products with fine teeth, for example velvet, are used.

That is, processing is carried out in at least two stages using different types of files. At the first stage, rough processing is performed, and the finishing of the surface of the part is carried out by bringing the workpiece to the required parameters.

File Features

Handmade products of this type can be divided into the following categories:

1. Locksmith - we can say that this is a multi-purpose tool. It can be found in almost any enterprise, workshop, or household.
2. Needle files are small-sized products designed for processing small parts. They are widely used by engravers, jewelers, and pattern makers. In addition, there are needle files that are indispensable when processing in hard to reach places.
3. Sharpeners - they are used for sharpening saw chains, hacksaws, etc.
4. Rasps are products with the largest teeth and are used to work with non-metallic materials, that is, in cases where the usual one is not suitable for solving the assigned production or household tasks.

As already noted, working teeth are applied to the working surface. It can be single or double. For processing soft materials, a tool with an arc cut is used.

Point teeth are made on the surface of the rasp.

Types of notches

There is a classification option based on the type of notch applied. A little has already been said about single and double execution.

Meanwhile, there are two types of double notching. The first is called crossover. This is, in fact, a combination of a single and a second, small (auxiliary) one, it is performed at an angle to the base one. At the intersection points of the grooves, the resulting chips are broken. This type is most often used in the production of bench files.

The second version of the double notch is called Oberg. Auxiliary grooves are less frequent. In fact, this option can be called intermediate between single and double notches in terms of the quality of part processing.

Numbering of notches

The application is determined by taking into account the type, size and configuration of the applied teeth. To obtain a working surface, various technologies are used:

• roll;
• milling;
• slicing and many others.

Many manufacturers, in order to increase labor productivity, use specialized equipment that allows them not only to speed up the production of these products and expand the number of their types, but also to maintain their quality at the appropriate level.

The size of the tooth directly depends on the size and type of notch applied per unit length, usually 1 cm. That is, the fewer grooves per centimeter of length, the larger the size of the cutting tooth. In practice, files with cuts from 0 to 5 are used.

The largest types include teeth with No. 0 and No. 1. They are used when it is necessary to remove a layer of metal from 0.05 to 0.1 mm in one pass. Such a tool has the following disadvantage - low accuracy, it ranges from 0.1 to 0.2 mm.

Files with tooth sizes No. 2 and No. 3 are used in cases where it is necessary to remove a layer of metal from 0.02 to 0.06 mm. The accuracy of such a tool is from 0.02 to 0.05 mm.

For finishing surfaces, a product is used that allows you to remove a layer of metal from 0.01 to 0.005 mm. An instrument of this type is sometimes called a velvet instrument.

Geometric parameters of the notch

In accordance with the requirements of GOST 1465-80, set out in clause 2.1. On the surface of the tool, the notch is applied at an angle of 65 degrees relative to the axis.

In addition, it is also specified what technology it should be used to carry out. For example, round files can be made either by knurling or threading. All other types must be made using a notch.

Types of files

There are many ways to classify file types. They can be divided according to their cross-sectional shape, geometric dimensions, and cutting tooth dimensions.

Often this tool is often divided into the following types:

• files with coarse and fine cuts;
• garnishes, etc.

File shape

Centuries of experience in using this have led to the fact that manufacturers have mastered the production of this product of various types. For example, a flat profile can have two types of endings - straight and sharp.

File appearance

Today, a large number of this tool of various shapes are used. It can be classified not only by the shape of the section, but also by the shape of the bar itself.

Use of files of various shapes

Indeed, the shape of the bar largely determines the scope of application. That is, flat, used for processing flat surfaces located inside or outside the part. Square ones are used to develop holes of various shapes. Triangular has found its application in the processing of grooves and other parts. In addition, it is used for sharpening saws and other tools.

Semicircular, which can have a rectangular or pointed shape, are designed to work with convex or concave surfaces.

Round, used for working with round or oval holes. For processing gear wheels Diamond-shaped files are used.

Such an abundance of this tool (shape, size, etc.) can lead to confusion. And many sincerely believe that you should keep as many files as possible in your home workshop. But this is nothing more than a misconception. In fact, most surface treatment work can be done using tools of the following shapes - straight, round and triangular.

By the way, the service life depends on the material, heat treatment parameters and the size of the notch.

Teeth size

In addition to the tooth size, products of this class differ from each other in the cutting density.

For rough surface treatment, products with large notches are used. It is called No. 1; there are from 5 to 15 teeth per centimeter. Its use makes it possible to remove a fairly thick layer of material in one pass, especially from soft materials; I call files of this type wrangler files.

Files No. 2 have from 14 to 25 grooves per centimeter of surface. This is perhaps the most popular type of this instrument. In fact, this file is most often used in practice.

Indeed, it can be used to process almost any material. But there is one subtlety: when working with soft metals or wood, after a fairly short time the notch will be clogged with processing waste. This is why it is necessary to clean the work surface with a wire brush.

Products with notches from 26 to 80 grooves per 1 centimeter are used for final surface treatment. After correct processing, there are practically no traces left on the surface.

File hardness - good or bad

Many people believe that the higher the hardness of the steel, the better the tool. In part, this statement has a right to exist, but it in no way applies to metal files.

High hardness leads to increased fragility of the tool. Those who use them frequently can attest that this tool can break if dropped on a concrete floor.

Sharpening a cutting tool using a file

To the group cutting tools include cutters, cutters, axes, saws and many others. The operating mode and the material from which the cutting tool is made determine the frequency of its sharpening. This operation is performed in two passes. The first is the sharpening itself, the second is finishing cutting edge before necessary requirements. That is, it must be brought into working condition. The cutting edge must be sharpened to a certain angle, it must have a certain form. These parameters are determined by the material of the part.

During the finishing process, burrs formed during the primary sharpening process are removed from the cutting edge.

For finishing cutting tools, products with fine notches are used. These can be files, bars and other abrasive materials. Finishing operations can be performed either using special equipment or manually.

Which notch to choose

When choosing any tool, first of all you need to understand what goals should be achieved when processing the part. Files are most often used to remove layers of material. Undoubtedly, if we're talking about If you want to remove material within 0.1 mm, then it makes sense to use files with cuts No. 0 or No. 1.

To perform more fine work For example, when preparing a surface for coating, you can use a tool with a notch No. 2 - No. 4.

To perform work related to threading the cutting edge, grinding the surface and other particularly precise work, so-called velvet tools are used.

How to make a file handle

Those who often use a file in their work sooner or later are faced with the fact that its handle becomes unusable and therefore the question of replacing it arises. Of course, you can go to a hardware store and buy a ready-made part. But that's not always the case The best decision. As a rule, they sell handles made of plastic or unknown types of wood. This is why many people prefer to make pens with their own hands.

Material selection

Practice shows that for the pen optimal material You can consider materials such as walnut, maple. These are quite durable materials; in addition, they have an attractive texture.

But in addition to the material for the handle itself, you will need to select glue. For connection components For the tool, it is advisable to use adhesives based on epoxy resin.

How to make it

To make a handle, you can use a lathe. If this is not possible, then you can remember your childhood and sharpen it with a knife.

When making a handle, it makes sense to maintain the following dimensions:

• working part diameter 25 – 30 mm;
• working part length 120 – 150 mm;

The depth of the hole for securing the tool shank should be slightly longer than the shank itself.

The final operation in the manufacture of a file handle is to treat its surface using abrasive sandpaper. This is necessary so that there are no burrs left on the surface of the handle that could dig into the worker’s hand.

Regulatory framework - some features

GOST 1465-80 has been adopted on the territory of our country. This document defines regulatory requirements to this product. In particular, it defines the shapes of manufactured products. In addition, surface hardness requirements are standardized in a separate section.

GOST also regulates the packaging procedure finished product. Thus, each finished tool must be packaged separately. The type of marking also plays an important role. Consumer packaging must contain information about the hardness of the finished product.

Download GOST 1465-80

The files are distinguished by toe 1, edge 2, edge S with a notch, heel 4, shank 5, handle b (Fig. 123).

Rice. 123. File:
1 - toe, 2 - edge, 3 - edge, 4 - heel. 5 - shank. 6 - handle

Files are made from steel grades U12, U12A, U13, U13A, ShKh6, ShKh9 and ShKh15 with a cut length of 100; 125; 160; 200; 250; 315; 400 mm.

Types of notches. The notches on the surface of the file form teeth that remove chips from the material being processed. File teeth are obtained on sawing machines using a special chisel, on milling machines milling machines, on grinding machines- special grinding wheels, as well as by rolling, broaching on broaching machines - broaches and gear cutting machines. Each of these methods cuts its own tooth profile.

Each tooth has a clearance angle α, a sharpening angle β, a rake angle γ and a cutting angle δ (Fig. 124).

Rice. 124. Teeth geometry

The best results when filing are achieved with the following file angles:

1. for a file with notched teeth: α = 20-30°, β = 60-70°, γ = 0-15°, δ = 90-115°, i.e. the cutting angle is greater than 90°, the rake angle is negative; As a result, the tooth scrapes thin chips from the workpiece;
2. for files with milled and ground teeth: α = 20-25°, β = 60-65°, γ = 2-10°, δ = 80-88°;
3. for files whose teeth are obtained by drawing: α = 40°, β = 55°, γ = 5°. δ = 90°. The extended tooth has a socket with a flat bottom. These teeth cut better into the metal being processed, which significantly increases labor productivity. In addition, files with such teeth are more durable, since the teeth do not become clogged with chips.

The fewer notches per 1 cm of file length, the larger the tooth. There are files with a single, or simple, notch (Fig. 125, a), with a double, or cross (Fig. 125, b), with a rasp (Fig. 125, c) and an arc (Fig. 125, d).

Rice. 125. Types of file cuts:
a - single, b - double, c - rasp, d - arc

Single cut files can cut wide chips, equal to the length the entire notch. They are used for filing soft materials (brass, zinc, babbitt, lead, aluminum, bronze, copper, etc.) with low cutting resistance. In addition, these files are used for sharpening saws, knives, as well as for processing wood and cork. A single notch is applied at an angle of 70-80° to the file axis.

Double-cut files are used for filing steel, cast iron and other hard materials with high cutting resistance. Practice has established that the highest productivity with the least resistance is provided by files with notches forming an angle of 125-130°.

In double-cut files, one cut is called the bottom or main cut, and the other is called the top or auxiliary cut. The lower notch is made at an angle of 55°, and the upper notch is made at an angle of 70-80° to the axis of the file.

The rasp cut is made in the form of staggered pyramidal projections and grooves, forming relatively large and sparse teeth. Files with such a notch are used for filing babbitt, lead, zinc, as well as leather, wood, rubber, rubber, bone, etc. These files are made from steel U7, U10, U12.

Files with an arc cut (milled) have greater durability, as they wear out evenly along the entire length.

The distance between adjacent teeth of a notch is called the pitch. The main notch has a larger pitch than the auxiliary notch..

There are also files in which the pitch of the upper notch varies unevenly, gradually increasing or decreasing.

Due to the different cut pitches, individual teeth will remove large or small chips, causing the file to work more evenly. The surface of the workpiece, no matter what size it is, is processed much better with such a file.

According to the nature of the work, files are divided into five groups: 1) metalworking files general purpose, 2) needle files, 3) rasps, 4) special, 5) machine.

General purpose machinist's files. Depending on the size of the tooth, the cut and the number of teeth per 1 cm of length, these files are made with a cut of six numbers: 0; 1; 2; 3; 4; 5: No. 0 - bastard files, which have 5-13 teeth per 1 cm of length (large notch); No. 1 - personal files, which have 13-25 teeth per 1 cm of length (medium notch); No. 2; 3; 4; 5 - velvet files with the number of teeth per 1 cm of length 25-80 (the smallest notch).

Brushed files No. 0 are used for rough processing, when it is necessary to remove a large layer of material (at least 0.25 mm). The allowance to be removed with a hog file depends on the nature of the surface being processed and is equal to 0.5-1.0 mm. A file with a garnish notch removes a layer 0.05-0.1 mm thick in one stroke and gives a processing accuracy of 0.1-0.15 mm.

Personal files No. 1 are used after the main layer of material has already been removed with a garnish file. For processing with a personal file, an allowance of no more than 0.15-0.35 mm is usually left. A personal file removes a layer 0.02-0.08 mm thick, and a fairly high processing accuracy is achieved - 0.025-0.05 mm.

Velvet files No. 2; 3; 4; 5 are used only for the most precise finishing, fitting, finishing of parts and grinding surfaces. These files remove a very small layer of metal 0.0025-0.05 mm thick and give high accuracy processing - 0.01-0.05 mm.

Depending on the shape of the workpiece, files of various profiles are used.

Flat blunt-nosed and sharp-nosed files (Fig. 126, a) are used for filing external or internal flat surfaces. In a blunt-nosed file, only one edge has a notch, this allows you to file one plane without damaging the other, which is connected to it at an angle of 90°.

Rice. 126. Shapes of file sections:
a - flat, b - square, c - triangular, d - semicircular, d - round, f - rhombic, g - hacksaw

Square files (Fig. 126. b) are used for sawing square, rectangular and polygonal holes, as well as for filing narrow flat surfaces.

Triangular files (Fig. 126, c) are used for filing sharp corners, such as outside parts, and in grooves, holes and grooves.

Semicircular files (Fig. 126, d) are used for sawing out curves in corners and grooves complex profile, as well as angles less than 60°. The flat side is used for filing surfaces, and the semicircular side is used for sawing concave surfaces (semicircular recesses).

Round files (Fig. 126, h) are used for sawing round or oval holes and concave surfaces.

Diamond files (Fig. 126, e) are used for filing the teeth of gears, toothed disks and sprockets, as well as for removing burrs from the teeth of these parts after processing them on machines.

Hacksaw files (Fig. 126, g) are used for filing internal corners, gear teeth, wedge-shaped grooves, narrow grooves, planes in triangular, square and rectangular holes.

Rasps. Used for sawing wood, leather, bone and other soft materials. Large teeth and spacious rasp grooves allow you to file soft metals and alloys - lead, zinc, babbitt, etc.

According to GOST 6876-54, rasps are made of steel grades U7, U10, U12.

General purpose rasps come in four types - flat, blunt and pointed, round and semicircular. Rasp lengths are 250 and 350 mm.

Small files are called needle files; they are used for cutting out small holes, processing grooves and other small and precise surfaces that are inaccessible to processing with bench files. Needles have a notch for 1/2 or 1/3 of their length and, depending on the number of notches per 1 linear line. cm are divided into six classes: 1st class - pugnacious, 2nd class - personal, 3-6th classes - velvet. File length 120; 160 mm, and the length of the cut part is 40; 60; 80 mm.

According to the cross-sectional shape, needle files are distinguished (Fig. 127): round, semicircular, flat pointed, oval, hacksaw, square, triangular ordinary, flat blunt, triangular one-sided, grooved, diamond-shaped (GOST 1513-53).

Rice. 127. Needle files:
a - round, b - semicircular, c - flat sharp-nosed, d - oval, e - hacksaw, f - square, g - triangular ordinary, h - flat blunt-nosed, i - triangular one-sided, k - grooved, l - diamond-shaped

Needle files are made from steel wire grades U13A, U13, U12 and U12A with a diameter of 2; 2.5; 3.5 mm. The length of the files is 120 and 160 mm.

A significant amount of filing work in assembly, repair and tool shops is carried out using filing machines and machines. Some designs of filing machines and machines are described in § 5 of this chapter. By design, machine files are divided into rod, disk, plate and shaped heads.

Rod files (Fig. 128, a) on machines receive reciprocating motion. For mounting in the machine, they have two shanks or one shank and a cone.

Rice. 128. Machine files:
a - rod, b - disk, c - shaped

Disc files (Fig. 128,b) are used for cleaning castings, forgings, and deburring. In the machine they are attached using mandrels and receive a rotational movement. The disk is made with a diameter of 150-200 mm and a thickness of 10-20 mm. The teeth are milled or notched.

Lamellar files are rectangular, oval or semi-shaped bars round section. They are intended for machines with a flexible shaft, with a continuously moving belt to which they are attached with rivets.

Shaped heads (Fig. 128, e) are used for filing and cleaning curved holes, grooves, shaped recesses, as well as deburring. They are made solid (with a shank) and mounted and are attached to the end of the flexible roller of a filing machine.

Special files. To process shaped surfaces and hard-to-reach places, such as large rings, oval-shaped cavities, stamp grooves, discontinuous surfaces, etc., use special files manufactured according to factory standards. The notch, shape and size of such files are very diverse.

Labor productivity with special files is 1.5-2 times higher compared to processing with conventional files.

File handle attachment. In order to make it more convenient to hold the file while working, a wooden handle made of maple, ash, birch, linden or pressed paper is placed on its shank.

The surface of the handle should be smooth and polished. The length of the handle should correspond to the size of the file. Handle sizes are given in reference books.

The diameter of the handle hole should not be greater than the width of the middle part of the file tail, and the depth of the hole should correspond to the length of the tail. The hole for the file is drilled or burned out, and to prevent the handle from splitting, a steel ring is placed on its end.

To attach a file, its shank is inserted into the hole in the handle, and right hand do not hit the head of the handle very hard on the workbench (Fig. 129, a). To remove the handle from the file, grasp the handle tightly with your left hand, and with your right hand apply two or three gentle blows to the upper edge of the ring with a hammer (Fig. 129, b), after which the file easily comes out of the hole.

Rice. 129. File handle attachment (a), handle removal (b)

It is forbidden to use a file with a cracked handle wrapped in wire; the shank may come out of the handle and injure the worker’s hand.

Files with a handle screwed onto the shank are safe to use (Fig. 130). The design of such a file allows the use of replaceable blades that have different notches on both sides and allow for quick change.

Rice. 130. File with replaceable blades and screw-on handle

Rules for handling files. Under the influence of the removed shavings, the file teeth are chipped and worn out; in addition, small shavings (sawdust) are packed between the file teeth and the tool loses its cutting ability.

Files can also wear out prematurely due to careless handling.

To protect the file from clogging with shavings when filing soft and viscous metals, it is recommended to rub the file with chalk, and when filing aluminum - with stearin.

It is necessary to protect files from even minor impacts that can damage the teeth. Files should be stored on wooden stands and at the same time ensure that they do not come into contact with each other and do not become corroded.

Rapid wear of the file teeth causes filing of cast iron workpieces, along the crust, or forgings with scale. Before filing, the crust or scale must be cut off with a chisel.

It is also necessary to ensure that oil does not get on the files; it reduces the cutting ability of the file. For the same reason, dirt and dust, especially abrasive ones, should not be allowed to get on them. Do not wipe the file and the surface to be filed with your hand.

A new hog file should first be used for filing soft materials (bronze, copper, brass) and only then processed hard materials(cast iron and steel). This will increase the service life of the file.

Experienced mechanics use one side of the file, and file the second only after the first has become dull.

The file teeth are cleaned with steel cord brushes (Fig. 131, a); if they are not available, scrapers made of aluminum, brass or other soft metal are used (Fig. 131, b).

Rice. 131. Cleaning files:
a - cord brushes, b - soft metal scrapers

Solid steel or copper wire is not suitable for this purpose, since steel spoils the notch, and copper wire coats the teeth with copper.

Files clogged with sawdust of wood, ebonite, rubber, fiber, plastic, are cleaned with scrapers made of steel or brass wire with a flattened end or immersed for 15-20 minutes in hot water and then cleaned with a cord brush. Cleaning is carried out along the notches. It is recommended to clean personal files with scrapers rather than cord brushes.

Cleaning oily (greasy) files is done by rubbing a piece of hard birch charcoal along the rows of cuts, and then with a metal brush.

File selection. When starting work, the mechanic must select the type of file, select its length and cut number.

The type of file is determined by the shape of the workpiece or product being processed. For filing flat surfaces, choose flat files; for filing grooves rectangular section- square; for processing external corners - flat; for internal corners 90° - flat, square; for angles over 60° - triangular.

The choice of file length is consistent with the size of the surface being processed. When filing, use the entire working surface of the file.

When choosing files, they are often guided by the following: the length of the file should be 150 mm greater than the length of the surface being processed; for example, when the size of the surface to be filed is no more than 50 mm, files with a length of 200-250 mm are used; for a surface of 50-100 mm, files with a length of 250-300 mm are used. For finishing and filing thin plates, it is necessary to take short files (100-160 mm), since their notches are finer. If you need to remove a large allowance, choose a file 300-400 mm long. They have a larger notch and processing will be carried out much faster.

The file is selected based on the cut number depending on the size of the allowance to be removed.

For rough processing, files with notches No. 0 and 1 are used, for finishing - No. 2, for final filing, finishing and finishing - No. 3; 4 and 5.

You cannot file soft metals (copper, tin, etc.) with a personal file, since the chips quickly get clogged into the grooves between the teeth and the file does not remove the chips, but slides on the surface.

Do not use a personal file to remove large allowances. This will require significant processing time. Making personal files is more expensive than bastard ones.

Classification of files

TO category:

Metal filing

Classification of files

Files according to their intended purpose are divided into the following groups: general purpose, special purpose, needle files, rasps, machine.

General purpose files are intended for general metalworking work. According to the number of notches (cuts) per 1 cm of length, they are divided into the following six numbers: 0, 1, 2, 3, 4 and 5.

Files with notches No. o and 1 (garnish) have the largest teeth and are used for rough filing when it is necessary to remove a large layer of metal - 0.05 - 0.10 mm. The processing accuracy of this file does not exceed 0.1 -0.2 mm.

Files with notches No. 2 and 3 (personal) are used for finishing filing of products with an accuracy of 0.02 - 0.05 mm. The removed metal layer does not exceed 0.02 - 0.06 mm.

Files with cuts No. 4 and 5 (velvet) are used for final finishing products. They remove a layer of no more than 0.01 -0.03 mm with a processing accuracy of 0.01 to 0.005 mm.

Files are divided into the following types:
A - flat, B - flat pointed (Fig. 137, A, B) are used for filing external or internal flat surfaces, as well as sawing slots and grooves;
B - square files (Fig. 1, B) are used for sawing square, rectangular and polygonal holes, as well as for filing narrow flat surfaces;
D - triangular files (Fig. 1, D) are used for filing acute angles of 60° or more, both on the outside of the part and in grooves, holes and grooves, for sharpening wood saws;
D - round files (Fig. 1, D) are used for sawing round or oval holes and concave surfaces of small radius;
E - semicircular files (Fig. 1, E) (section segment) are used for processing concave curved surfaces of significant radius and large holes (convex side); planes, convex curved surfaces and angles of more than 30° (flat side);
F - rhombic files (Fig. 1, N) are used for filing the teeth of gears, disks and sprockets, for removing burrs from these parts after processing them on machines, as well as filing angles over 15° and grooves;
3 - hacksaw files (Fig. 1, 3) are used for filing internal corners, wedge-shaped grooves, narrow grooves, planes in triangular, square and rectangular holes, as well as in the manufacture of cutting tools and dies.

Rice. 1. Files by section shape: A, B - flat, C - square, D - triangular, D - round, E - semicircular, F - rhombic, 3 - hacksaw

Flat, square, triangular, semicircular, rhombic and hacksaw files are made with notched and cut teeth.

Hacksaw files are produced only upon special order. Rhombic and hacksaw files are made only with cuts No. 2, 3, 4, 5 in length: rhombic 100 - 250 mm and hacksaw - 100 - 315 mm.

Special-purpose files are manufactured according to departmental standards: for processing non-ferrous alloys, products made of light alloys and non-metallic materials, as well as calibrated ones.

Files for processing non-ferrous alloys, in contrast to general-purpose metalworking files, have different, more rational notch angles for this particular alloy and a deeper and sharper notch, which ensures high productivity and durability of the files. Files are produced only flat and sharp-nosed with cut No. 1 and are intended for processing bronze, brass and duralumin.

Files for processing bronze have a double cut: the upper one at an angle of 45°, and the lower one at an angle of 60°, for brass 30 and 85°, respectively; for duralumin 50 and 60° Marked with the letters CM on the shank.

Files for processing products made of light alloys and non-metallic materials. General-purpose files used by mechanics when processing products made of light and soft alloys (aluminum, duralumin, copper, babbit, lead) and non-metallic materials (plastic, getinax, textolite, plexiglass, wood, rubber, etc.) have a fine cut , so during operation they quickly become clogged with chips and fail. Files with a special holder are used to eliminate these disadvantages. This file has dimensions of 4 x 40 x 360 mm and a cut in the form of arc grooves for the release of chips at a significantly increased pitch compared to general purpose hog files. The productivity of such files increases two to three times.

Tared files are used in all cases when it is necessary to check the hardness in parts of the product that are inaccessible to the diamond tip of the device (the side profile of a gear tooth, the cutting blade of a milling cutter, etc.) and when testing the hardness directly in the workshop at the hardener’s workplace. Files are calibrated to a certain hardness depending on the hardness of the products. They differ from suitably normalized files by their increased and stable quality.

Diamond files are used for processing and finishing of carbide parts of tools and dies. A diamond file is a metal rod with work surface and cross section the desired profile, on which a very thin diamond layer is applied. The diamond coating on the working part is made of various grain sizes for preliminary and final finishing.

Nadsrili. Small files are called needle files; they are used for patterning, engraving, jewelry work, and for cleaning hard-to-reach places (holes, corners, short profile sections, etc.).

Needle files have the same shape as bench files. Needle files are made from steel U13 or U13A, U12 or U12A is allowed. The length of the files is set to 80, 120 and 160 mm. On the working part of the file, teeth notches are applied at lengths of 50, 60, 80 mm. The needle files have a cross (double) notch: the main one at an angle A = 25° and an auxiliary one at = 45°. The narrow side of the file has a single notch (main).

Depending on the number of notches per 10 mm of length, needle files are divided into five types: No. 1, 2, 3, 4 and 5. Depending on the type, needle files have from 20 to 112 notches. A notch number is applied to the handle of each file: No. 1 -20 - 40 notches; No. 2 – 28-56; No. 3,4 and 5 – 40-112 notches per 10 mm length.

Diamond needle files are used for processing carbide materials, various types ceramics, glass, as well as for finishing carbide cutting tools. Needles are made from natural and synthetic diamond powders of various grain sizes with rectangular, square, round, semicircular, oval, triangular, rhombic and other cross-sectional shapes. When processed with needle files, surfaces of 9-10th roughness classes are obtained.

Rice. 2. Needles: a - rectangular blunt-nosed, b - rectangular pointed-nosed, c - square blunt-nosed, d - triangular blunt-nosed, e - triangular blunt-nosed, f - round blunt-nosed, g - semicircular blunt-nosed, 3 - oval blunt-nosed, i - rhombic blunt-nosed, k - hacksaw, l - grooved; L - working part, 1 - handle length, d - handle diameter, b - profile width, h - needle file thickness

Rice. 3. Diamond files

Rasps are designed for processing soft metals (lead, tin, copper, etc.) and non-metallic materials (leather, rubber, wood, plastics), when ordinary files are unsuitable due to the fact that their notches quickly become clogged with chips and they stop cutting.

Rice. 4. Rasps

Rice. 5. Machine files

Rice. 6. Born files: a - shaped heads (bored files), b - disk, c - plate, d - device for fastening disk files

Depending on the profile, general-purpose rasps are divided into flat (blunt-nosed and pointed-nosed), round and semicircular with a notch No. 1-2 and a length from 250 to 350 mm. The rasp teeth have big sizes and spacious grooves located in front of each tooth.

Machine files (rod files - for filing machines with reciprocating motion) of small sizes are secured in special cartridges, and medium-sized files have shanks on both sides, with which they are secured in the holder centers of the machines. These files are made in the same profiles as bench files, with the same types of cuts as general purpose files.

Rotating files (burn files, disk and plate files) are used for filing and cleaning surfaces on special filing machines.

Bornapills are shaped heads with notched or milled teeth. They are made whole (with shanks) and mounted (screwed onto a mandrel).

Burner files have angular, spherical, cylindrical, shaped and other shapes. They are used to process shaped surfaces.

Disc files are used for cleaning castings, forgings, and removing burrs on machines such as emery grinders. The disk is made with a diameter of 150 - 200 mm and a thickness of 10 - 20 mm. The teeth are milled or notched.

The discs are secured using a device.

Lamellar files are bars of rectangular or round cross-section with a corresponding notch.

These files do not have shanks; they are attached to a flexible, continuously moving belt with rivets.