Cutting sheet material into pieces is carried out using various instruments. Roller shears for cutting sheet metal are popular, the trend is explained by the simplicity of the design and high performance. The device is used in industrial and small workshop environments.

Characteristics of scissors

The intended purpose of roller knives is to cut steel sheets up to 1 mm thick. They are necessary at the site for the production of ventilation ducts, when working with roofing metal, when building a fence and arranging the roof.

The mechanism is used to produce semi-finished products for subsequent bending of profiles for various purposes. The equipment is installed in car body repair shops. In auxiliary production, blanks are prepared for the assembly of racks and cabinets.

Scissors with rollers will successfully replace manual option or guillotine due to a number of advantages:

Compact dimensions and light weight.
Simple device.
Convenient to use.
Just getting set up.
Suitable for working with sheets of different materials: aluminum, tin, steel, roofing iron.

The processed product is obtained with a clean cut and no burrs or bends. Leaf view It is easy to cut metal with such a device.

Scissors can be purchased at specialty store or make it yourself. It all depends on the volumes performed and the economic component. With a daily cutting rate of 30–50 meters or more, an industrial design will be required.

Description of scissors

The task of dividing a sheet of metal into parts is solved by destroying the strength bonds on a local segment.

The power part consists of two cutting roller discs with multidirectional rotation. Their cutting edges lie in the same plane. When rotating, the rollers are pressed into the surface and cutting occurs due to shear deformation. The sheet material is fed to the tool by friction of the knives against the metal.

The design of the cutting mechanism includes two rotating rollers located one above the other. Depending on the design of the cutting part, roller knives are distinguished:

With one inclined edge for straight longitudinal cutting and cutting out round and ring workpieces.
With parallel position of knives, cutting material in strips with high quality. They occur most often.
With several inclined edges for convenient cutting of curved, round and ring-shaped workpieces with a small radius.

All types of scissors provide cutting of sheet material with high quality, without the need for subsequent cleaning of the cut edge.

To increase productivity and obtain an even cut, the housing with roller knives is installed on a stationary machine.

The cutting equipment includes a frame with supporting surfaces, equipment for fixing the material and roller knife. The latter contains a body made of steel gauge, an overhead handle, cutting rollers, and a mechanism for adjusting gaps in several planes.

The material for cutting discs is tool steel.

The manufacturer sets an average service life of 25 km to cut sheet metal with a thickness of 0.5 mm. With increasing thickness, the service life decreases proportionally. The cutting element is subject to regrinding, which significantly increases the service life.

How to make a roller knife

A purchased model of roller shears, even of the simplest design, is unprofitable for purchase in a small workshop or private household. It is not necessary to use it often, and the device is expensive. The optimal solution is making scissors with your own hands.

The design of the mechanism may be different, but at the core there will always be a cutting knife in the shape of a roller. The selected material for making knives determines the performance of the device and the quality of the cut. Knives must be strong and reliable, with a surface hardness significantly greater than the hardness of the material being cut. Otherwise, you won’t get a high-quality cut; the edges will have to be processed additionally.

Homemade roller knives are made from bearings. To do this, the ends are sharpened to create a cutting edge. The drive roller is mounted on the handle. When working with it, the knife is pressed into the workpiece. The lower roller is installed permanently. During the cutting process, you need to press the handle with the roller with one hand and pull the sheet of metal with the other.

Selecting a larger bearing diameter will increase cutting speed.

For convenience and precise cutting, additional guides are installed.

Adjustment is carried out using oval holes, a set of spacers and special bolts.

If you are proficient in metalworking techniques, manufacturing a cutting device takes 7–10 days, including setup.

Lever metal shears are a popular tool that is used to perform various procedures for cutting materials - sheet metal, tin, profiles, wire. Although there are all kinds of hand tools available in the market of this type, there are often adventurers who prefer to make guillotine devices with their own hands.

Guillotine devices for cutting metal are based on the lever principle of operation;
The cutting process is carried out by a pair of cutting surfaces;
In this case, the length of a knife for metal can be about 20 centimeters;
One cutting surface is firmly fixed to the base of the machine and is subject to all the pressure while cutting metal;
The moving part is located on the bed, which facilitates high-precision cutting;
On a stationary blade, hand tools provide a special groove for the slide. It is designed to move the slider as needed. The groove carries out movements in one plane;
The moving part of the cutter is connected to the slider;
The working stroke of this slider is usually 15-30 millimeters;
The movable knife is firmly connected to the handle, the length of which is about 500 millimeters. Due to this, during the cutting process you can apply less force with your own hands in order to cut sheet metal of the required quality;
Guillotine devices have a metal body, which significantly extends the service life and increases the loads that the tool can handle when cutting sheet metal, profiles, and rods;
Cutting knives are made of high-strength tool steel. This allows you to cut sheet metal parts with minimal effort and without deformation of the cutting edges.

Using guillotine hand tools for cutting metal, you can process it yourself:

Sheets of steel up to 5 millimeters thick;
Products made of sheet aluminum up to 6 mm thick;
Brass 6 mm thick;
Metal profiles with a section of 6 by 80 mm;
Steel rod No. 13.

Species

To purchase manual cutting tools or make guillotine devices with your own hands, you will first need to become familiar with the types of these devices.

Structurally, lever scissors are almost no different from each other. Therefore, the main difference lies in the type of drive used. Hence the classification, dividing devices into three main categories.

Hand cutters. These are the most simple devices cutting applications that require you to manipulate the blade with your hands to get the job done.
Electrical. They are distinguished by high productivity and speed of work. To cut profiles, sheet metal, rods, you do not need to apply any physical effort.
Hydraulic. The most powerful types of equipment, the operation of which depends on a hydraulic drive. Widely used in cutting the thickest and most durable materials. They are used extremely rarely in everyday life.

When choosing lever tools for cutting sheet metal, rods, profiles, you should pay attention to one more important parameter— length of the actuator. The capabilities of the scissors directly depend on the length of the blades.

There are three main types of scissors according to length:

Short. Are different small in size, allow for through cutting of material;
Long. These guillotine devices provide straight cutting, minimizing the effort and time required to process workpieces;
Combined. Can cut sheet metal, metal profiles, rods in different ways. Distinctive feature- ability to carry out contour cutting.

It is impossible to use lever scissors for processing small items. Their main purpose is cutting and cutting large workpieces and parts.

All factory lever shears on the market and homemade devices can be divided into two large groups:

Stationary. Are securely fixed on the desktop, workbench with special devices, provided by the design machine;
Portable. Also designed for fixing to work surface. But in this case, fastening is carried out with bolts or clamps. If necessary, they can be easily removed and moved to another area to perform the assigned tasks.

Hand scissors

Manual guillotine devices are the most often preferred choice for home use. Their simple drawings allow you to make simple desktop units with your own hands. They do an excellent job cutting thin sheet metal.

But before you choose these hand tools, you need to know what varieties they come in. Such knowledge allows you to make homemade metal scissors if you wish. Although desktop factory models do not cost much, they will not require you to make significant financial outlays to purchase a tool for use at home with your own hands.

Manual guillotine devices are divided into several types:

With a straight blade. These guillotine devices allow cutting sheet metal and other workpieces only in straight lines;
With curved blades. If you need to make sheet metal complex elements, make holes on the workpieces, it is recommended to choose just such devices;
Chairs. Useful thing for those who need to cut a thick layer of paper or a large stack of sheets at once. Saves time, requires relatively little physical effort;
Finger. Due to their thinnest cutters, these hand scissors are able to make the required neat holes;
Lever. These are desktop devices that need to be firmly fixed to a table or workbench.

Manual lever units are designed for through and straight cutting along straight lines. Often found in workshops, they are often used at home due to their capabilities and functionality.

Guillotine, lever, manual, electric, hydraulic types scissors are widely used in metal processing.

Once you have lever shears at your disposal, you should familiarize yourself with the basic rules for using them. This will not only allow you to cut metal workpieces correctly, but also preserve own hands in integrity.

Wear strong protective gloves before you begin. This way you will protect yourself from sharp metal sheets. They themselves can cause injuries, unpleasant cuts, if you simply pick them up to place them on a cutting machine.
Securely secure your lever attachments according to the manufacturer's instructions. For different models scissors may have their own installation features on the desktop. Therefore, first of all, study the factory instruction manual.
Place the sheet of metal you are cutting perpendicular to the blades of your lever shears. Hold the base with your right or left hand, depending on whether you are right- or left-handed.
Gently and gradually press the handle of the scissors from top to bottom.
Remember to wear closed shoes to avoid being injured by falling metal scraps.
For a desktop, choose designs with a strong and stable base.

Working with lever shears for metal is not difficult, but it requires compliance with certain safety measures.

Lever shears are used to cut sheet metal, tin, and cut aluminum profiles and wire. The stores offer many models from different manufacturers any price categories. However, there are craftsmen who make this useful and simple tool with their own hands.

Lever shear device

lever scissors Corvette

The operation of manual metal shears is based on the principle of leverage. The cutting of the material is carried out by two cutting surfaces about 20 cm long. In this case, one surface is rigidly fixed to the base, and this is where all the pressure is applied. The movable cutter is also fixed to the frame. A groove is selected in the fixed blade to move the slider. It moves like a hinge in one plane.

The movable part of the scissors is attached to the slider. The working stroke of the slider is 15 - 32 mm. The movable panel is equipped long handle(about 50 cm), which increases the applied force by 20 times or more. Therefore, metal is cut quite easily.

The body of the lever scissors is metal, the cutting surfaces are made of tool steel. On average, the dimensions of the instrument are 56 x 18 x 45 cm and weighs about 30 kg. Using such equipment, you can cut a steel sheet with a thickness of 0.5 cm, aluminum or brass 0.6 mm, a profile with a cross-section of 6x70 mm, or a steel rod No. 13 with your own hands.

Types of lever scissors

The designs of lever cutters do not differ in variety; the main difference is in the type of drive:

manual - the most primitive device; by pressing the lever, the cutting blade is set in motion;
electric - they work very quickly and are highly efficient. Cutting metal on such equipment does not require any effort from the worker;
hydraulic - powerful, driven by a hydraulic drive. Widely used when large forces are required, for example, for cutting reinforcement or rods.

Hand scissors are divided depending on their purpose and design:

with straight blades - used only for cutting in a straight line;
with curved cutters - they cut out elements complex shape and holes;
chair - used for cutting thick layers of paper;
finger - make holes with very thin incisors;
lever - permanently mounted on a workbench.

Manual lever device allows you to perform through or straight cutting only on a straight line.

In addition, the tools differ in the length of the actuators:

with short blades for through cutting;
with long cutting surfaces - for straight cutting;
combined scissors for all types, including contour scissors.

Cutting small parts It is impossible to use lever scissors; they are convenient for large cutting or chopping jobs.

The tool can be stationary or portable type. For work, both types are firmly fixed on a workbench or bed. This is the only way to cut metal accurately and safely. To secure portable scissors, use clamps or bolts.

Rules for working with lever shears

Before starting work, you must put on seals so as not to get cut by the sharp edges of the metal sheet!

Fix firmly hand tool on the table surface;
place the sheet of metal perpendicular to the blades, holding it with your main hand (right hand for right-handers);
Smoothly and carefully press the handle from top to bottom.

While working, you need to protect your feet from falling pieces of cut metal. Edge falls are especially dangerous, so you should not work barefoot or in open shoes. To install the scissors, choose only a strong, non-wobbly base.

Homemade lever scissors

drawing of lever scissors: 1 - lower cheek, 2 - fixed blade, 3 - movable blade, 4 - upper base, 5 - screw for fixing the blade (2 pieces), 6 - bolts 4 pieces, 7 - knife lever, 8 - earring, 9 - lever, 10 - screw, 11 - bolt for tie (2 pieces)

The frame of this model of hand scissors is assembled with your own hands from a pair of corners 7.5 x 7.5 x 0.8 cm. The fixed knife is attached to a horizontal base using a pair of screws. To align with the movable blade, the top of the base is cut in half. Holes are made in the blades, countersunk for M8 screws 24 mm long, countersunk.
The following are installed on the upper base using hinged fasteners: bottom surface blade and lever of the knife (dimensions 6.5 x 3 x 0.6 cm), on the upper part there is a lever (24.5 x 1.8 x 0.7 cm) and an earring (6 x 1.8 x 7 cm), providing mobility.

The blanks are cut out with your own hands using a hacksaw. The blades are machined from hardened steel, the sharpening angle is 30 degrees.

First we collect all the details in finished machine, we are setting up. Then we take it apart and paint it. When the paint dries, we assemble it clean.

Since the presented structure is quite small, it is mounted on a workbench in a vice. You can install the tool permanently on a workbench. To do this, the base is welded to a corner, which is screwed to the workbench. Spacers are used to adjust the blade ratio.

drawing of manual lever shears for metal

This model of hand scissors is complemented by a detailed drawing. Metal cutting is done with a pair of blades, each 10 cm long. The movable blade is attached to the slide on a crank mechanism. The crank eccentricity is 16 mm and gives a maximum amplitude of 3.2 cm. We attach a 50 cm long handle to its tail.

It is recommended to make a stationary version of the scissors, which will be securely attached once to the working surface with M10 bolts. For fastening, paws with holes are provided. The body of lever hand scissors must be made of high-quality steel 45 or 40, and the blades from grades P18, P9 or U10.

Scissors made according to this drawing have been working successfully for more than 2 years, coping with steel sheet up to 3.5 mm thick.

Video with detailed description drawings, design and manufacture of lever shears for metal:

DIY roller knife

Cutting metal at home is a rather tedious process. And its quality often leaves much to be desired, forcing additional processing of the resulting edges. The situation can be largely corrected by using special devices, including those made by yourself. Today we will talk about one of these devices, namely the roller knife.

Roller knives for metal

The roller knife is gaining more and more demand and popularity today. This is due not only to the high productivity of such a device, but also to its fairly simple design. The principle of operation of the mechanism is simple - two cutting disc rollers rotate in different directions, pressing into the surface of the metal and thus cutting it. Friction between the metal and the knives ensures the smooth movement of the workpiece along the tool.

In the vast majority of cases, roller knives for cutting sheet metal include two rotating rollers - an upper and a lower one. Depending on the variation of the cutting element used, such tools can be classified as follows:

Parallel position knives - used for cutting metal into strips, while providing very acceptable quality;
Edges with one inclined - this group allows not only longitudinal cutting of material, but also cutting out ring and round workpieces;
Knives with several inclined - such devices make it possible to effectively cut round, curved or ring-shaped workpieces with a small radius.

It is worth noting that all of the above variations cope perfectly with cutting sheet steel, while the cut edges do not require additional attention and subsequent processing.

Homemade roller knives

With all its undoubted advantages, even the most simple model A roller knife has a pretty decent price. This is the reason why it is inappropriate to purchase it for one-time work or periodic use. However, the optimal solution from a financial point of view still exists - a roller knife can be made with your own hands at home.

The design of such a device can be very different. The most common variations are presented below (photo, photo 2). But in any case, the main part remains unchanged - the cutting knife. It should be made from the most durable and reliable steel alloy, the strength parameters of which must necessarily exceed those of the material being cut. If this condition is not met, the quality of the cut will be low, which will require additional processing of the cut edges.

Practice shows that the working life of factory-made knives is about 25 km of sheet steel, provided that its thickness is 0.5 mm. With greater thickness, the resource will be correspondingly lower. However, the tool can be sharpened without any problems and continue to function effectively.

If we talk about the resource homemade knives, then it is directly dependent on the material from which the cutting parts of the unit are made.

What can a knife be made from?

The options can be very different; here you need to pay attention to what exactly you plan to cut. So, if it is not the most durable sheet steel in its structure, including aluminum, galvanized metal and other similar materials, the most ordinary bearings will be a completely suitable solution. True, for this you will have to pre-sharpen their ends.

To carry out cutting, one of the rollers, the one that will play the role of a drive, is installed on the handle, due to which the knife will be pressed to the metal. Please note that the larger the diameter of the bearings, the faster the material can be cut.

In order for the cutting process to take place with maximum comfort and precision, the device can be additionally equipped with guides - this will not be particularly difficult, but it is guaranteed to serve you well in the future.

The resulting tool is quite versatile and can be used in conjunction with a wide variety of metalworking equipment, including sheet metal bending machines, which can also be made independently at home.

How to make a guillotine for cutting metal with your own hands?

In a home workshop or small business producing products from thin sheet metal, sheet metal shears, more simply - a guillotine - will never be superfluous. The driven version can be installed, for example, in a garage, and a manual guillotine will not take up much space at all. If you have quite a large number of manufacturing options (in drawings, videos or descriptions), as well as some adapted components from some decommissioned equipment, making homemade metal shears is an accessible reality.

Homemade hand guillotine

The work of the simplest metal scissors

The principle of cutting with guillotine (sheet) shears is that the knife beam of the device, to which the movable part of the tool is attached, along the working end must have an angle of 1.5...3°, as a result of which metal cutting occurs non-simultaneously across the entire width. This reduces the cutting force, but requires a technique that would compensate for the shear of sheet metal (tin, thick cardboard, etc.) during cutting. Thus, a reliable clamp is required.

The main components of the saber guillotine

To drive a homemade guillotine, you can use a low-power electric motor, since the energy intensity of the process is low. But according to the results of calculating the maximum cutting force, it is often sufficient manual drive, For example, lever type(V homemade devices This is often what is suggested). You will also need reliable guidance of moving parts during the cutting process, as well as a rigid support surface for the bed. In this case, the parts of the homemade guillotine and the product itself will not be elastically deformed.

The drawings usually indicate the limits of the thickness and width of the sheet metal or tin for which the device is designed. If the entire process of obtaining sheet shears with your own hands is carried out independently, then the design begins with clarifying the power characteristics of cutting and choosing a mechanism diagram.

The initial data for choosing a design are:

the type of material with which operations will be performed;
maximum sheet dimensions in terms of thickness, length and width;
separation accuracy;
limit overall dimensions scissors;
drive type.

Mechanical guillotine shears

The manual device is the simplest in design. It includes:

support table on which the initial workpiece will be located;
two or four racks that will provide the scissors with strength and stability;
a rotary axis with plain bearings (rolling bearings are unsuitable, since the clearances during operation of such a guillotine will change significantly, which will quickly lead to jamming);
knife beam, which provides seats for mounting replaceable knives;
fixed knives, which are mounted on the front end surface of the work table;
a rotary lever that will forcefully move the beam during cutting;
clamps for fixing metal.

Do-it-yourself production starts from the table. Its dimensions must be sufficient for convenient placement blanks, taking into account places for fixing clamps: there must be at least two of them, on each side of the sheet. The thickness should prevent deflection under deformation forces. The easiest way is to use a steel plate, which you install on the channels yourself. The joints can be bolted flush with the top surface, or welding can be used. The front end must be ground to ensure evenness of the subsequent fit of the stationary knife to it.

The next stage is to obtain the support posts yourself. They must be made from a solid profile. Will fit square pipes made of high-quality medium-carbon steel, or channel. The section size can be easily calculated from the maximum load on the racks, which is the sum of the self-weight of the components of manual guillotine shears for metal, and the cutting force P, kN.

The latter is calculated according to the dependence:

k is a coefficient that takes into account possible unevenness of the working gap, bluntness of cutting edges, quality of the material being cut, etc. Typically k = 1.05…1.3;

B – maximum width of the metal sheet, mm;

s – maximum metal thickness, mm;

σ ср – shear strength of the material, MPa.

For the materials most commonly used in everyday life, this parameter is, MPa:

for low carbon steel – 280…2
for medium carbon steel – 300...400;
for high carbon and stainless steel – 400…500;
for sheet metal, aluminum – 65…80;
for copper, brass – 180...200.

When assembling the racks with your own hands, it is imperative to maintain the parallelism of the supporting surfaces and their perpendicularity to the axis of rotation of the knife beam. For these purposes it is better to use laser level. The floor where the scissors are installed must be made level and durable. Do-it-yourself installation of equipment on compacted soil, laminate and other options for coating concrete with polymers is not allowed.

A particularly important moment is making a knife beam with your own hands: its profile must be made such that during the turning process the movable knives gradually come into contact with the metal being cut. There are two options for this:

profiling along the contour of the saber, with a gradual increase in the radius of curvature as it approaches the lever handle;
pyramidal profile with a bevel angle of no more than 5...60 (at a larger angle, the metal will begin to deform and bend in the direction of the rotation axis).

The saber-shaped profile is more difficult to make, but it provides a smoother integration into the metal being cut.

For better direction of the body, it is placed either in a special groove on the table, or - with increased deformation forces - special guides are designed, which are attached to the racks with your own hands.

Handmade homemade guillotine

It is better to make the rotation axis from high-quality carbon steel, and then harden it to a hardness of at least 42...45 HRC. Bearing bushings are made of OF10-1 bronze, which has good wear resistance.

For the manufacture of tools, tool steels U10 or U12 are used, hardened to a hardness of 48...54 HRC. Hardened knives are carefully polished with your own hands, after which they are sharpened at an angle of 85...90°. The gap between the knives is taken within 3...6% of the thickness.

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Simple and easy-to-use scissors for cutting thin sheet metal are easy to make in any workshop. They can cut strips of the same width without marking a cutting line, identical workpieces at right angles, and trim the flanges of squares to a given width. Performing these operations simple scissors for metal requires marking, takes a lot of time, and the cut line is not always smooth, especially if the workpiece is long.

The scissors frame is made of two squares with a cross-section of 75x75 mm, a length of 200 mm, fastened together with M6 screws.
Two identical knives 120 mm long are made from old flat files with a cross-section of 8x35 mm or from tool steel U7A or U8A.
The fixed knife is attached to the frame, the movable knife is attached to the lever with No. 6 screws.
Files should be annealed at a temperature of 750-800° to a dark cherry-red color and slowly cooled in air. Then cut to length and drill two holes in each of them for fastening. After the holes are drilled, a notch is ground on adjacent planes of the files. grindstone. Then the knives are heated to a temperature of 830-900° (to a light red color) and quickly cooled in water or mineral oil. To prevent them from warping during hardening, they should be lowered into water vertically. After hardening cutting edges knives are sharpened and tucked on a block. The lifting angle of the lever is adjusted with a limiter so that the planes of the knives do not come out of contact.

1 - base; 2 - screws securing the frame to the base: 3 - screws connecting the angles of the frame; 4 - screws for fastening Noshes; 5 - lever fastening nuts; 6 - washer; 7 - gasket; 8 - limiter screw; 9 - limiter; 10 - guide ruler; 11 - retractable bar; 12 - clamping screw of the strip; 13 - holes for screws for fastening the corner cover; 14 - guide ruler stopper; 15 - knives; 16 - bed angles; 17 - lever; 18 - screws for fastening the corner cover; 19 - corner pad for attaching the trimmed square.

The lever is made of steel 8-10 mm thick and 30 mm wide. It must be rigid enough to ensure that the working planes of the knives fit snugly against each other.
The frame is equipped with a guide ruler made of steel 6-8 mm thick. It moves in the grooves parallel to the plane of the knives.
The working planes of the ruler are cut or filed strictly under the ruler and square. The position of the ruler on the frame is fixed with two M6 wing stoppers. In the lower plane of the ruler, a groove is cut or milled at a right angle to the front edge, in which a retractable bar with a cross-section of 20x2 mm moves, allowing workpieces to be cut at an angle of 90°. The position of the bar is secured with an M5 clamping screw and washer.
To prevent the square from bending when cutting the shelf allowance using lever scissors, a removable pressure corner pad is made from sheet steel 0.8-1 mm thick. It has the cross section of a non-equilateral square. One shelf should be 1-1.2 mm less than the thickness of the guide ruler on which the square is installed; the other is 15 mm wide. IN larger shelf The corner trim and holes for the screws are sawn into elliptical shapes with a round file.
If when cutting thin material it bends, which means the planes of the knives are poorly adjusted. If the width of the flange of the square being cut is not the same, the corner pad is installed with a large gap.
Depending on the quality of the knives, lever shears can cut sheet material up to 1 mm thick. It is not recommended to cut steel or other thick wire so that the blades of the scissors do not become jagged.
Finished scissors are painted oil paint, except for working planes, which are lubricated with machine oil.
The bed is attached to the work table with screws, bolts or a clamp. The scissors will be portable if they are mounted on a base made of a 30 mm thick board measuring 500x200 mm.

How to make a homemade metal guillotine?

The presented guillotine, made by hand, works on the principle of lever scissors and is designed for cutting sheet metal with a thickness of no more than 3 mm.

It is made from improvised materials, in particular from an old file and scraps of metal structures.

Manufacturing a guillotine consists of several stages. First, it is necessary to carry out drawing work in order to precise definition product dimensions. The applied scale is 1:1.

It is also recommended to draw a kinematic diagram, with the help of which it will be possible to determine the dynamic parameters of moving parts without taking into account the acting forces.

Drawings of parts drawn on paper are printed on a printer and then cut out. The machine model is assembled from the cut out parts. This is done in order to verify the correctness of the calculations made and the exact correspondence of the dimensions of each individual component in the context of the functioning of the entire mechanism as a whole.

It is very important to determine the cut level indicator. It will be located at the intersection of the movable blade with the base, which is conventionally indicated by a line drawn in pencil.

The next step is to select pieces of scrap metal of suitable size, followed by template drawing of the contours of future components on them. It is at this moment that the paper scraps from under the animation turn into an important stencil.

In this case, the blanks were scraps of a corner and a sheet piece of iron lying around. And as a result of intensive work with a grinder or a gas cutter, the main parts of the metal scissors were obtained. These are two ears, a handle, a body holder and the body itself.

A base of two welded corners is attached to the body of the guillotine. Their thickness is 50 mm. Pay attention to the space taken into account for entries in the mode: “sheet up”, “sheet down”. There is also free space for a file. In this case, one must proceed from the parameters of its thickness plus the required gap.

Then, with the help of mounting bolts, a sequential assembly process occurs. The handle is attached to the main structure of the scissors through two ears. After which one end of the body holder is screwed to it. The second one is connected to the handle.

The result should be something like this. Provided that no mistakes were made in the previous stages, the moment of complete cutting should occur when the handle reaches a horizontal position. The minimum movement of the handle against the background of the maximum stroke along the radius must also be achieved.

The blank for the two blades was an ordinary old, and therefore ground, file. To begin with, it should be cut into two parts. Three holes are drilled in each of them for fastening. After this, the blade profile is formed and the edges are directly sharpened.

The images show the mounting locations of the two cutting knives. The movement of the upper knife should not be obstructed by other parts of the machine. It is important to position the profile in such a way that across the entire width of the cut, the interaction of the knives occurs at an angle of 6-8 degrees.

Ready-to-use homemade lever scissors using clamps or specifically for this purpose drilled holes are securely fixed on the working surface of the workbench.

Provided that basic technological rules are observed during the manufacture of the machine, it will certainly show very high efficiency. And it will cut both paper sheets and 3mm iron with ease.

Video: DIY manual guillotine for cutting metal.

Lever shears are used to cut sheet metal, tin, and cut aluminum profiles and wire. The stores offer many models from different manufacturers of all price categories. However, there are craftsmen who make this useful and simple tool with their own hands.

Lever shear device

The movable part of the scissors is attached to the slider. The working stroke of the slider is 15 - 32 mm. The movable panel is equipped with a long handle (about 50 cm), which increases the applied force by 20 times or more. Therefore, metal is cut quite easily.

The body of the lever scissors is metal, the cutting surfaces are made of tool steel. On average, the dimensions of the instrument are 56 x 18 x 45 cm and weighs about 30 kg. Using such equipment, you can cut a steel sheet with a thickness of 0.5 cm, aluminum or brass 0.6 mm, a profile with a cross-section of 6x70 mm, or a steel rod No. 13 with your own hands.

Types of lever scissors

The designs of lever cutters do not differ in variety; the main difference is in the type of drive:

manual - the most primitive device; by pressing the lever, the cutting blade is set in motion;
electric - they work very quickly and are highly efficient. Cutting metal on such equipment does not require any effort from the worker;
hydraulic - powerful, driven by a hydraulic drive. Widely used when large forces are required, for example, for cutting reinforcement or rods.

Hand scissors are divided depending on their purpose and design:

with straight blades - used only for cutting in a straight line;
with curved cutters - they are used to cut out complex shaped elements and holes;
chair - used for cutting thick layers of paper;
finger - make holes with very thin incisors;
lever - permanently mounted on a workbench.

The manual lever attachment allows for through or straight cutting on a straight line only.

In addition, the tools differ in the length of the actuators:

with short blades for through cutting;
with long cutting surfaces - for straight cutting;
combined scissors for all types, including contour scissors.

Cutting small parts with lever scissors is impossible; they are convenient for large cutting or chopping work.

The tool can be stationary or portable. For work, both types are firmly fixed on a workbench or bed. This is the only way to cut metal accurately and safely. To secure portable scissors, use clamps or bolts.

Rules for working with lever shears

Before starting work, you must put on seals so as not to get cut by the sharp edges of the metal sheet!

Firmly fix the hand tool on the table surface;
place the sheet of metal perpendicular to the blades, holding it with your main hand (right hand for right-handers);
Smoothly and carefully press the handle from top to bottom.

While working, you need to protect your feet from falling pieces of cut metal. Falls on the edge are especially dangerous, so you should not work barefoot or in open shoes. To install the scissors, choose only a strong, non-wobbly base.

Homemade lever scissors

Option 1

The frame of this model of hand scissors is assembled with your own hands from a pair of corners 7.5 x 7.5 x 0.8 cm. The fixed knife is attached to a horizontal base using a pair of screws. To align with the movable blade, the top of the base is cut in half. Holes are made in the blades, countersunk for M8 screws 24 mm long, countersunk.
On the upper base, with the help of hinge fasteners, are installed: on the lower surface, the blade and lever of the knife (dimensions 6.5 x 3 x 0.6 cm), on the upper part the lever (24.5 x 1.8 x 0.7 cm) and the earring (6 x 1.8 x 7 cm), providing mobility.

The blanks are cut out with your own hands using a hacksaw. The blades are machined from hardened steel, the sharpening angle is 30 degrees.

First, we assemble all the parts into the finished machine and set it up. Then we take it apart and paint it. When the paint dries, we assemble it clean.

Since the presented structure is quite small, it is mounted on a workbench in a vice. You can install the tool permanently on a workbench. To do this, the base is welded to a corner, which is screwed to the workbench. Spacers are used to adjust the blade ratio.