Long live the snail. How to make a snail - cold forging machine (drawings).

Elements in the form of curls, made of rods, are widely used in the design of local areas and the interior of residential premises. Special devices are used for their manufacture. One of them is a snail. Home craftsmen often construct this device themselves from scrap materials. If you also want to know how a snail is made for cold forging with your own hands, then this article is for you. From it you will learn the operating principle of this device, its advantages and varieties, simple drawings and self-assembly technology.

Cold forging method

The method involves using an important property of metal - plasticity.
With the help of various mandrels and mechanical devices, the rod is bent in different directions, twisted, and forms various three-dimensional shapes. As additional processing, welding and metalworking operations are used to connect parts of workpieces. Entry-level machines are quite simple and are driven by the muscular strength of the master working on them. The minimum set of forging equipment for cold forging of metal includes:

Bending machines, or Gnutiki, are used to bend workpieces at a given angle and radius.
Twisters, or torsion bars, are used to twist a workpiece (or group of workpieces) around the longitudinal axis
Wave - used to create periodic bends in different directions.
Snail forging machine - used to create spiral-shaped curls at the end of a rod.

Is it possible to master cold forging yourself? Yes, it is enough to have basic skills in metalwork, design and machining.

Many home craftsmen have made a snail - a cold forging machine on their own, without using expensive components.

Pros and features of the process

Cold forging is a popular type of work due to the fact that it can be used to create unusual parts of various shapes and sizes.

Using a cold forging machine, you can make a fence for a flower bed, a decorative lantern, an unusual fence, railings or handles for a bench and other elements.

Another advantage of cold forging is that it is quite easy to make a machine with which you can create such parts with your own hands. This will help you save on the purchase of expensive equipment.

The cold forging process consists of three main elements: bending, pressing and welding of parts. The equipment needed for this process is quite simple and compact, you can do it yourself and it will not take up much space in your workshop or garage.

You can start learning metal processing with cold forging, because... this process is easier and safer because you don't have to deal with high temperatures like other types of welding.

For this process, a ready-made template is usually used - that is, blank parts.

Of course, cold forging has its own subtleties, they mainly consist in the fact that the part is easily damaged or deformed during the process: forged elements often break, and the defect cannot be corrected, so forging must be done very carefully.

However, using a high-quality machine and a drawing of the future part, you can easily learn how to create products with twisted, wavy and other unusual shapes. You can see the options in the photo above.

The process of processing blanks through cold forging occurs in several stages. The first step is to create a template or drawing of the future design.

It is necessary to calculate the dimensions of the product in order, firstly, to purchase the required amount of material, and, secondly, to properly configure the machine.

Different machines provide different possibilities for creating patterns - this depends on the complexity of making the tool.

For example, the simplest do-it-yourself machines can only bend products, while with the help of more complex models you can create patterns, etc.

After the template or drawing is ready, you need to buy the required amount of material in accordance with your calculations. For cold forging you will need iron rods, you can buy them in the store.

Rods for cold forging should not be too thick, otherwise they will be difficult to bend. The next stage is making the parts yourself:

The most important thing here is to set the settings correctly so that during operation of the machine the parts are not damaged or deformed, because it will be impossible to fix the problem.

Lastly, the completed parts are secured to the frame. This happens by welding.

You need to be especially careful when welding with your own hands with thin-walled tubes, because... It’s easy to burn through them, and then the design will become faulty and you’ll have to do it all over again.

You can watch the entire forging process in the video before you start working on your parts.

But before you start cold forging, you, of course, need to make the machine that is necessary for this. The “Snail” machine is the most common apparatus for processing metal products using the cold forging method with your own hands.

You can see all the stages of creating the machine in the video - there is nothing complicated about it, and almost everyone will be able to cope with this task themselves.

How to build a curl?

There are plenty of sketches of curls for artistic forging on the Internet, but when you try to adjust their sizes to those required for yourself, it often turns out that the product loses spectacularly due to a seemingly insignificant violation of the proportions. Therefore, it is also desirable to be able to construct forging patterns of curls that obviously have aesthetic advantages.

Templates for cold forging of artistic curls - volutes - are built on the basis of mathematical spirals. The most commonly used is the logarithmic spiral; it is one of the widespread natural forms expressing the fundamental laws of nature. The logarithmic spiral is found in the shell of a snail, in our hearing aids, and in the form of a treble clef in musical notation; in the neck of the violin itself too.

Construction of forming templates for cold forging based on spirals

The principle of constructing a logarithmic spiral by points is that when the radius that forms it is rotated, starting from a certain initial R0, by a fixed angle φ, its length is multiplied by the divergence index of the spiral p. For volutes p, as a rule, take no more than 1.2, because a logarithmic spiral diverges (unwinds) very quickly; on pos. In Fig. a logarithmic spiral with p = 1.25 is shown as an example. To make it easier to build a spiral at points with sufficient accuracy for forging work, take φ = 45 degrees.

In the case when a denser arithmetic spiral is required, when the radius forming it is rotated by the same 45 degrees, 1/8 of the spiral pitch S is added to the previous radius, pos. B. In both cases, R0 is taken equal to or greater than the diameter d of a workpiece of uniform cross-section, pos. A. If the initial end of the workpiece is pointed, R0 may be less than d, up to the plasticity limit of the metal.

It remains to decide how to lay a visually harmonious spiral with a given opening size a. To solve this problem analytically, i.e. using formulas with any precision specified in advance, you will have to solve cubic and higher-order equations. There are no computer programs for numerical technical calculation of volutes on the Internet, so we will use an approximate method that allows us to get by with one working and, possibly, one test graphical construction. It is based on the assumption that for small p the sums R2+R6 and R4+R8 do not differ much. The step-by-step algorithm for constructing a volute for a forging template follows from here:

Based on the available material, we determine R0;
we take the number of turns of the volute w according to the principle: as God puts it on the soul of the left hind paw of a beloved cat;
Using the data from the table in Fig., we calculate the diameter of the volute b such that it is slightly smaller than the width of the opening under it a, see pos. G;
We calculate the working initial radius R using the formula for pos. G;
we build a volute profile on a scale point by point;
if necessary, we accurately adjust R using the same formula and build the profile of the working template completely.

Note: if you calculate intermediate values from the table, do not forget - they must be taken in geometric proportion!

What is produced using the cold forging technique

That is, where we can direct the result of our work. And, as practice shows, there are not so few options. Especially if you live in a private house or have your own dacha.

All kinds of furniture for your garden. From small and cozy benches to large fences on terraces, consisting of branched forged ornaments. Various barbecues, chairs and more.
Fencing of all types. Moreover, both for the external type, along the perimeter of the territory, and for the internal purely visual gradation.
Coverings for gazebos.
Sports equipment of different types.
Frame buildings for growing crops.

As you can see, if you have a drawing to make a cold forging machine with your own hands, then it is possible to subsequently acquire a huge number of extremely useful things for the garden and home. As they say, there would be a desire.

Maybe you need a punch? Main concepts

You've probably already noticed that on our website we love to point out anything that's wrong. Now, too, we will not change ourselves: the concept of “cold forging” in its usual meaning is fundamentally incorrect, read carefully, we will explain.

First, what is forging: it is the processing of metals heated to forging temperature, that is, to the temperature when the metal becomes soft and can be deformed. Blacksmithing is all about forging - with a hammer, an anvil, a forge and mighty bearded blacksmiths wearing leather aprons.

Blacksmithing products are an exclusive and expensive business. And, in general, it is already exotic, if we exclude stamping, which is done automatically and in huge volumes.

Stamping is the extrusion or deformation of metal using a stamping press with a special matrix - a nozzle at the end. This is what it is - a punch that is made from the highest strength steel. Stamping can be hot, with heating of metals to forging temperature, and cold, without any heating. You don’t have to look far for an example of cold stamping - these are all metal drink cans.

Types of forging machines.

We are finally approaching working with metals in a cold way - without heating. Question: is it possible to deform metal without heating? Answer: yes, you can. The only way is mechanical. It is called a not very serious word - riveting or cold hardening. To do this, you will have to hit the metal with a hammer until you are stupefied until its structure begins to change significantly.

This process is precisely cold forging - mechanical deformation of metal blanks using mechanical blows with a hammer. If you decide to take up peening forging, then we say hello to your family and neighbors in advance - they will face serious challenges.

But seriously, there are fans of cold forging using the riveting method, we wish them success and move on to pseudo-cold forging, as they used to call it.

Mechanical deformation of metals using various machines without heating is more correctly called metal bending, because in this method of metal processing, craftsmen bend metal rods. They don't do anything else - they just bend. Another question is how and where they bend, along what axis, but all these are artistic aspects of metal bending, which we will also dwell on, but later.

The most important thing is that in the future we will call this process cold forging - as it is done in all sources, so that there is no confusion. It’s just that now we understand the methods and understand what the essence of the so-called “cold forging” is.

By the way, do you need a punch? It's a beautiful word. You won't be involved in industrial stamping of metal blanks, will you? But artistic forging with your own hands is a very real possibility at home. There is even light stamping along with punches... Let's look into it further.

Devices for bending metal elements “Snail”

To bend workpieces according to certain parameters, auxiliary conductors are used, called “Snail”. They serve as a special template that allows you to reproduce dozens and, if necessary, hundreds of similar parts. The “Snail” machine for cold forging bends parts without additional heating.

The work is based on the deformation of metal according to a certain principle. To bend, you have to put in a lot of effort. Therefore, craftsmen quite often equip “Snail” devices with an electric drive. Geared motors help to develop significant forces with a limited shoulder of force application. The torque in the processing area can reach several tens of kilograms.

If such work is performed only due to the physical strength of the blacksmith, the worker will get tired quite quickly. Its productivity will drop to zero. And with a mechanical assistant, hundreds of workpieces can be produced per shift.

It must be taken into account that bending of workpieces is an intermediate stage in the manufacture of complex structures. They still need to be installed in the right place and welded. Only then will an intermediate result be obtained. Then the product will need to be painted and installed at the place of order. All operations will require not only time, but also the physical strength of the master.

Structurally, the device can be:

Non-separable, then it will be used to bend parts only to certain lengths. The resulting spiral has certain limitations in use.
Prefabricated (there are additional fragments to increase the bending time), and the device can be used to bend long parts. Large sized parts will be received.

To work with parts from small profile pipes, some make manual devices. They involve the use of levers to help move the workpiece around the mandrel. The finished parts are removed from the end, slightly loosening the tension.

Most often in such cases I use square bars □8...12. Some craftsmen manually bend profile pipes 15·15 mm with a wall of 1.5 mm. For larger products, a mechanical drive is required.

Making a torsion bar machine

Torsion treatment is fundamentally different - it is a screw twisting of the rods along. This machine is very easy to make with your own hands. The main thing in it is to ensure a strong fixation of the two ends of the metal rod; the success of screw twisting depends on this.

At one end the rod should hold tightly, at the other it should rotate with the help of a lever. The components of the torsion bar are a metal cylindrical blank made of a profiled pipe and two fastening elements with a locking device. They can be made from bearing units.

The clamps have nuts welded into the bolts that are tightened to hold the metal rod.

If your plans include “pump up your biceps and triceps,” be sure to make a torsion bar machine and start twisting the rods by hand. Torsion forging is not for the weak, you will develop excellent muscles in the upper shoulder girdle. But one way or another, it is better to make the lever for rotation longer, it will be easier.

Features of the snail

The author specifically decided to draw the reader's attention to a number of points. This will help you avoid some mistakes in the future. For example, having understood the structure of the snail and the principle of its functioning, someone will want to assemble their own device, different from those whose drawings will be presented below.

Such a device (if we are talking about equipment made by hand) will allow bending samples using the cold forging method with a cross-section (square side) of no more than 10 - 12 mm. This implies a “manually controlled” snail model. Almost no one has anything to do with larger samples in everyday life. The machine can be improved by installing a drive and an electric motor.

But how rational is this for a small home forge?

Cold forging is carried out at low speeds. A sharp change in the geometry of the metal leads to the appearance of cracks (ruptures).
You will have to not only select the power of the electric motor, but also the gear ratio of the gearbox. Plus, you need to mount the automation circuit with the installation of the corresponding elements (buttons, starter, and so on). All this significantly complicates the manufacture of the machine.

Which machine is most needed?

Do-it-yourself cold forging machine: which one is the most necessary and which one to start with?
There is no clear answer to this question; you must decide for yourself. To make a smart decision, let’s go through the main types of machines to have an idea of their functionality and, most importantly, DIY manufacturing methods. You should remember what materials you will have to work with during the cold forging process: these are metal rods or rods with a diameter of no more than 14 mm, squares and strips with a thickness of approximately 3 to 6 mm with a width of no more than 25 mm.

A complete gentleman's set of machines in the workshop for full-fledged work will look like this:

twister with snails for obtaining spirals of various radii;
bender for bending arcs and parts at different angles;
wave for curved parts and processing of metal pipes;
globe for obtaining large arcs from profiles;
flashlight for bending parts;
volumetric

You don't have to have it all at once. It’s quite possible to start work if you have two machines from the first two points - a twister and a bender. Forging with your own hands has a great advantage: you can choose what to do and where to start. Let's start the review with the most popular machine - the twister or the famous snail.

How it works and what it is like

At its core, it is the deformation of metal rods in the form of their bending. In order for the rod to deform without heating, it must be rigidly fixed to the machine template. This machine is not for weak hands: scrolling and deformation are done using manual effort.

Of course, the snail can be equipped with an electric motor drive. But before that, you need to carefully consider the feasibility of this drive. The main argument for an electrical addition is the large amount of work involved.

Snail for forging - drawing. The machine can operate in two different designs:

The simplest option is a template welded to the base. This is a monolithic conductor with a single curl option in the form of a template.
An option that gives more variety in curls is several modules with curls of different diameters, which are attached to one base.

Manual drive can also be provided in different options:

The lever can be any suitable device.
A lever that is attached to a frame and driven by a moving bearing.
More complex designs use as many as three levers that rotate the axis and the conductor attached to it.

How to make a snail for cold forging, which option to choose - easier or more difficult? The choice again depends on expediency, in other words, on your production plans: what are you going to do, with what productivity and in what quantity?

Types and purpose of forging machines

A machine for any purpose is used to facilitate manual labor. For cold forging, various equipment can be used, minimizing the physical effort of the master and allowing the following basic operations to be performed:

Machine for creating a shaped profile using cold forging

bending the profile at the desired angle or radius;
making spirals or curls;
longitudinal twisting of workpieces.

The variety of parts obtained allows you to arrange them in combinations and intricate designs, create a neat artistic canvas for fences and gazebos, symmetrical decor for park benches, as well as other items for various purposes.

Industrial bending machine, which allows you to obtain a workpiece with a given radius

Cold forging machines can be specialized (perform only one operation) or universal. There are the following types of special machines:

bending machines (bending machines) – allow you to bend a workpiece at an angle or a given radius (wave);
snails - twist the blanks into spirals and curls;
torsion bars - help to longitudinally twist a workpiece or several such parts at the same time;
stamping machines - they are used to make decorative clamps, shaped ends, and waves with fine pitches.

Universal machines include components of special equipment in various combinations.

Devices for cold forging are driven mechanically (manual machines) or by electric drive. Electrically driven equipment is characterized by speed and ease of processing workpieces. A cold forging machine, the price of which can be quite high, is characterized by high productivity. When there is no need for productivity and speed, then a manual machine will be quite sufficient to complete the work, especially if blacksmithing is a hobby.

Bent machine designed for processing pipes using cold forging

Is it possible to make a cold forging machine with your own hands?

You can buy a manual machine for cold forging in a specialized store that sells tools or order it online. The question is the price and solvency of the buyer. An alternative option is to assemble it yourself. The principle of operation will be no different from a product purchased in a retail chain, and the functions performed are absolutely identical to the factory ones. Additional advantages are a reduction in price, confidence that the design will not fail after the first use.

To begin with, it is worth familiarizing yourself with the design features of each type of machine in order to assess the possibility of its self-assembly.

A snail cold forging machine that allows you to create spiral elements

The torsion bar must twist metal rods, so its design assumes the presence of two elements that hold the workpiece. One of them serves as a clamp, and the other contains a rotating spindle, which, in fact, will twist the rod to the desired frequency of the helical wave. The device is quite easy to build yourself, and some craftsmen even make do with a vice and a simple hand crank.

The design of the bending machine is also simple, but it contains several mandatory elements, the assembly of which is impossible without specialized tools. The base is a massive metal plate with a groove in the middle into which a movable stop is inserted, moved by a worm mechanism. The other two cylindrical stops are stationary and are attached to the base on both sides symmetrically relative to the groove. It is the installation of stops that can cause difficulty, since holes for fasteners are drilled only on a specialized machine; such a workpiece made of high-strength steel will not yield to the influence of a drill.

Creating elements using the cold forging method on a homemade gnutik machine

A snail metal forging machine can have two types: with a collar or a lever type. The first option allows you to vary the shape of the bend during operation, however, it has a number of weak points in the design and is very demanding on the strength of the manufacturing materials. The second type is more stable, but less productive. Craftsmen consider the snail to be the simplest machine, the self-assembly of which will not cause difficulties.

Design specifications

The dimensions of the volute for cold deformation are determined by the diameter of the rolled product being bent and the required curl size. A sketch of the design of the forged product is first made. It is broken down into individual elements. For each spiral, a conductor is made - a snail or any other.

The simplest machines for cold forging have a massive, durable stand, at the upper end of which there is a groove for fixing a plate with a jig. Deformation is carried out due to the efforts of the master’s hands. He clamps the end of the rod and walks around the fixture.

If there is a rotary table and a lever, it is possible to produce volutes for rolling of a larger cross-section.

Using stamps

Matrices can be used both in manual forging and when using various presses and pneumatic hammers.

The technology of such forging works is as follows.

The stamp you need is placed on the anvil.
The workpiece is heated to malleable temperature.
The heated blank is placed on the stamp and the so-called metal rolling is carried out with hammer blows.
Excess elements are chopped off with a chisel or cut off.

When working with matrices such as lance, crow's foot, sheet and other similar ones, use rolled products in the form of a rod, circle or square of the appropriate size.

When a double-sided pattern is made, the heated blank is placed between the two halves of the matrix and, applying hammer blows, the configuration of the forged product is formed.

When using pneumatic or other mechanized hammers, the matrix can be installed on the hammer head (usually on the lower fixed one).

Dies are also mounted on various presses.

If during manufacturing it is necessary to make additional operations (for example, holes), the product is stitched separately using the appropriate tools.

The technology of using matrices became the founder of such a type of production as stamping. The manufacturing principle is similar, only machines are used instead of manual work.

Types, structure and principle of operation of the cochlea

Several varieties of the popular machine are used. All of them, regardless of the details of the cochlea device, use a general operating principle. A strip or rod of metal is forcefully pressed against a stationary template or against a movable ploughshare of the snail, forcing it to take the shape specified in the drawing.

monolithic non-separable volute using a fixed metal template. Used to produce series of identical products
removable design - bending is carried out around pins inserted into holes on a solid plate. Suitable for the production of unique parts with complex configurations, the cross-section of the rod is limited.
Collapsible volutes with rotation are more complex in design, but make it possible to obtain identical products of complex shape with great accuracy

Buy or make

It is better to pose the question in a different way. Do you need a large, high-quality batch of reference parts or just need to bend a couple of pipes? It’s still impossible to create a machine with minimal deviations using artisanal methods. And in terms of service life it will lose to the factory one. But for performing periodic (this is the key point) work, a homemade option is quite suitable. If the final parts do not require the highest dimensional accuracy. Otherwise, all that remains is to buy the necessary equipment.

Manufacturing technology of the “Snail” device

In a simplified way, the technological process of making a “Snail” machine with your own hands can be represented as a series of sequential operations.

A profile of the product to be manufactured is drawn on a sheet of paper. When drawing, the dimensions of the product are maintained. The drawing is needed only to obtain the profile of the part itself. Attention! When processing, the thickness of the workpiece is taken into account. A gap of at least 3...4 mm is needed, then the product can be removed after bending it in the device.
For most machines, a central stop is made. It will record the beginning.
Different craftsmen use their own fixation techniques, so their products can be distinguished by their handwriting.
A support plate is cut from a steel sheet. The center will be welded to it, as well as the spiral. The thickness of the plate must be at least 3 mm, as significant forces will be applied. The size of the plate in the future will also determine the parameters of the curl.
Using the spiral drawing, the workpiece is bent from the strip. When bending it, the parameters are controlled. The more accurately this element is manufactured, the easier it will be to manufacture elements for forging products. Attention! If it is necessary to make curls with more than one turn, you need to cut the spiral strip diagonally. Therefore, a strip of much wider width is used. The minimum size corresponds to the height of the profile that is going to be bent on the machine.
The device is placed on a special rack to make it easier to form finished products. For small parts it is convenient to place them on a vertical stand.
To make the job easier, weld the handle. It is installed on the reverse side so that it does not interfere with the installation and removal of workpieces.

Making a guide for the conductor

For these purposes, you will need an ordinary lathe of type 1K62 or 16K20, which is capable of cutting an Archimedean spiral, and, of course, an experienced turner. The “Archimedean spiral” function in lathes is intended for cutting special threads, but it is also quite suitable for obtaining a groove in the base plate, where the jig guide itself will then be located.

When preparing the machine, the following transitions are performed:

The small handle of the machine feed box is moved to the “Archimedes Spiral” position.
The required spiral pitch, which will determine the dimensions of the conductor, is set using a large handle.
The feed step is fixed by a lever, and the feed amount is determined by the depth of the groove in the plate (how to set this parameter will be discussed later).
After turning on the machine, the feed lever remains in the same position, and cutting is performed during the reciprocating movements of the spindle.
After each pass, the support is moved away from the end of the workpiece.

An example of obtaining an Archimedean spiral is presented in this video:

The fact that the frames show not metal, but plastic, does not fundamentally change anything: the spiral is obtained as a result of several successive passes of the cutter, which moves along a given path.

The dimensions of the spiral groove are determined based on the desired dimensions of the conductor and the height of its supporting surface. If in the first case everything depends on the size of the initial workpiece for the plate and the capabilities of the machine, then the depth of the groove should be calculated based on the height and thickness of the guide matrix.

Since in a cold state any metal has increased mechanical strength, then to make a guide matrix with your own hands you should use tool steel: for example, grade U7 steel according to GOST 1435-84. It is not recommended to use high- or medium-carbon structural steel such as steel 45 or steel 60G, since for tall volutes they may crack under the influence of a bending moment.

The dimensions of the guide matrix in plan are selected based on the available range of strip tool steel in accordance with GOST 4405-75. Since the jig must be compact, it is advisable to choose profiles 3×20, 3×25 or 3×30 with a maximum thickness deviation of 0.4 mm. When fitting the guide into the plate according to H11, the width of the spiral groove should be 0.5-0.7 mm greater than the width of the strip. The groove depth must be at least 1.5 times the strip height, i.e. 4.5 mm or slightly more. This parameter, by the way, will determine the thickness of the slab itself: it should be at least 6 mm.

The total length of the guide is determined from the cut groove in the slab (you can use a flexible tape measure or even regular thread to measure). Then they cut the required length of the strip “to size”, insert it into the groove and scald it along the contour (if the jig will produce only flat snails, then along the outer generatrix, and if three-dimensional, then along the inner one).

A support hook is bolted to the center of the conductor. It must have a lead-in section with which the workpiece is fixed at the initial moment of spiral formation (see Fig. 3).

Making a simple snail with your own hands

The snail machine usually has replaceable jigs of different sizes. First, a tool template for cold forging is drawn. Then a snail is made from it - a conductor, or rather an open stamp for winding. A snail of the desired shape is cut out and attached to the base.

The most aesthetically pleasing are spirals made according to the golden ratio principle. To do this, you need to draw a square with a side equal to the cross-sectional size of the rod for which the jig is being prepared. Then the compass is placed alternately at each vertex of the square and a line is drawn clockwise. The line should end near the beam on which the compass leg stands.

Drawings of a snail for forging

Novice craftsmen often neglect the importance of the design stage and make templates for cold forging by eye. This may be enough to “feel the metal” and understand the essence of the process with your own hands.

Drawing of a snail for forging

But if you want to get beautiful products as a result, and even more so if you are planning to produce a series of identical elements, then when manufacturing a machine you cannot do without accurate calculations of all parameters - bend angles and radii, torques, maximum forces and others. An accurate calculation will allow you to create with your own hands a high-quality snail machine for cold forging, which will last a long time and will delight you with ease of operation and high-quality aesthetic products.

Dimensions of the future machine

Before you start making a homemade jig for making decorative curls, you must first decide on the dimensions of the main parts.

In particular, we are interested in the dimensions of the central part and the curl. Based on the actual dimensions of the template, the dimensions of other structural elements are determined - for example, the frame on which the bending jig will be attached.

To create a snail machine for cold forging with your own hands, drawings and dimensions, if necessary, can be selected on thematic sites (or look for suitable options on forums on this topic).

Moreover, there are many different options for homemade designs. Let's look at one of them.

To make the drawing we will need:

square steel bar 10x10 mm;
A4 sheet of paper;
square;
pencil and compass.

First of all, we place a square rod in the middle of a sheet of paper and draw two parallel lines.

Then we apply the rod in a perpendicular plane at an angle of 90 degrees (we use a square for this), and draw two more lines.

As a result, in the center of the snail template we should get a square measuring 10x10 mm, from which four lines extend in different directions.

We take a compass, place it in the corner of the square, and draw a semicircle.

Then we move the compass to another corner (we go in order), and also draw a semicircle, continuing the previous line.

And we do this until we get a curl of the required size - the main part of the snail drawing.

After this, use a compass to draw a circle (in this case, the diameter of the circle is 43 mm).

The drawing is ready. Now you need to select a steel blank of a suitable diameter and cut off a piece about 30 cm long from it. The beginning of the curl (center) is cut out from this blank.

Draw a drawing yourself or download it from the Internet and print it on a printer - it’s up to you.

There is another way to make the central part - we will talk about it in detail below.

Making the central part of the conductor

Equipment and tools that will be required for work:

drill press or drill;
Bulgarian.

We cut out one large circle from sheet metal 18-20 mm thick (this will be the base plate) and four small circles to make the center of the jig.

The made center is attached to the frame using fastening bolts (the author uses hexagon bolts) - for this we drill coaxial holes in the workpieces.

Next, we draw out the profile that will need to be cut using a grinder. We process the workpiece with a petal circle.

At the next stage, we will look in detail at how to make a snail. You can use a square or strip as the starting material. If there is no strip, it can be cut from sheet metal of suitable thickness.

Making a conductor blank

We proceed to the next stage of work - we are engaged in the manufacture of a device for forging metal, along which the workpiece will be bent. Let's take a square rod as a basis.

On a bending machine we bend two curls of equal length. We fasten them together using masking tape and mark the locations of future holes using a center punch.

We drill holes and cut threads for the mounting bolts. The finished contour of the snail will be bolted to a metal support plate (frame).

When the main parts are ready, you can begin the final part of the work - assembling the cold forging machine with your own hands.

To do this, you will also need to make a bed, and think about what materials to make the base from and how it will be attached to the workbench or other supporting surface (for example, a horizontal platform located on a stand).

Final assembly of the machine

We make the machine bed. To do this, we need two pieces of metal corner and a metal plate that will be installed vertically.

The top edges of the plate will need to be rounded. We drill holes in the prepared parts, and then connect them together using bolts.

In the metal plate we drill a hole for the shaft, for which a steel round timber is used.

Additionally, it is necessary to drill mounting holes for attaching housing bearings. Next, screw the bearings onto both sides of the plate and install the shaft.

As you can see, there are no difficulties in making a snail for cold forging with your own hands.

Moreover, the variant of the conductor discussed above is collapsible, which is very convenient - this greatly simplifies the storage of the device when it is not in use.

We attach the central part to the base plate, then screw curls from a square rod onto the bolts.

We attach the shaft to the back side of the support plate. Then we install the assembled volute jig for cold forging on the vertical plate (bed) of the machine.

Additionally, we drill a hole in the plate and install a shaft with support bearings.

At the end of the main shaft we drill a hole into which we insert a handle made of a steel round bar. The step-by-step work process can be seen in the video below.

Drawings of a snail for forging

Beginning craftsmen often do without a drawing, drawing the contours of the snail on the base itself without any calculations. For the first time this is acceptable, but if you want to make a high-quality snail machine for cold forging, then you still need to use drawings in which all the parameters are calculated. Depending on the chosen type of snail design, there are different versions of their drawings, according to which these devices are made. For example, a diagram of the device of the snail shown in the photo is shown below.

The diagram also describes the operating principle of such a machine, which uses a drive using three levers that rotate the shaft and volute.

Bending is carried out after rigidly securing the end of the workpiece to the first curl of the template shape using a clamp and then winding the rod around the rotating spiral template while the shaft rotates.

After getting acquainted with the design of different types of “Snail” and the features of their use, as well as watching a video with examples of self-manufacturing of this device, you can begin to create the machine design of your choice. And if you have experience in making such devices, then you can share it in the comments to this article and give advice to novice craftsmen.

Making a simple part on a machine

The strip steel workpiece is cut to the required size. This size is usually clarified by drawing the finished product and its component elements.

The free end is placed in the center of the spiral. The workpiece is secured using an internal screw.

The “Snail” rotation is performed. The workpiece is pressed tightly against the guides. This requires some effort to obtain the desired product profile.

By turning the device further, a curl is made. If necessary, insert the other end of the workpiece and make a closed or open curl.

Usually the other end does not stay straight. It is also bent. Therefore, a distinction is made between internal and external reverse curls. Marks are made on the device itself using a marker or chalk. They are used as a guide when making curls with the required parameters.

As you can see from the step-by-step guide, using a simple set of tools, a homemade curl maker is easy to make. How much does it cost? Its price is determined by the cost of the blanks. Often the price is minimal.

Monolithic non-demountable snail

It is made like this:

First, a diagram of the future template with the required dimensions is drawn on a sheet of paper (sometimes the template diagram is applied directly to the base of the conductor). This must be approached responsibly, because after welding the finished form, it will not be possible to correct errors. The thickness of the outline of the form in the drawing should be the same as the thickness of the metal strip used for its manufacture. It should be at least 3mm. The coils must be placed at a distance of 12–13 mm from each other, so that a 10 mm deformable rod fits into the groove between them.
The base of the snail (preferably round) is cut out of a steel sheet with a thickness of at least 4 mm, the diameter of which is determined in proportion to the size of the template spiral and be larger than the size of the snail. Typically the diameter of the base is within 70 cm.
In accordance with the drawing, the desired curl shape is made from a 3mm thick metal strip. To do this, it is better to calcinate the workpiece so that it is easier to machine. After making the mold, the excess end of the strip is cut off, and the edges of the snail are cut into a cone and cleaned.
The finished form is welded to the base, which is mounted on the frame. Sometimes a template welded to the base is fixed to the frame using yews installed on it. To do this, a piece of timber is welded to the back side of the base of the form for gripping with a yew.

With the option of fixing the conductor in a yew clamp, you can easily change the templates and obtain different shapes of curls if you make several types, monolithically welded to the base of the devices.

Removable design

On the working base, first draw the contour of the snail with a mark along the contour of the holes for attaching the template.

Based on the sketch, a template is made from a thick steel strip and holes are drilled in it. It is attached to the base with bolts.

Forging a twisted shape should begin from the central curl. The end of the workpiece is inserted into the groove of the first curl of the form and pressed tightly against it. You can use a small clamping tool to secure the fixation. With force, the free part of the rod is screwed onto the template using a device - a lever. Advanced designs use a lever driven by a moving bearing mounted on it. The lever is made of a rod with a diameter of 20 mm.

You can watch the making of such a device in the video:

Collapsible snails with rotation

The snail template can consist of several parts, and the deformation of the rod occurs by rotating the conductor. This machine consists of the following elements:

thick metal base in the form of a disk or square;
a collapsible template fixed to the base area;
rotation shaft;
lever to drive the shaft.

The working base is made of metal, with a thickness of 4 to 10 mm.

The prefabricated template may consist of several parts that are connected to each other by hinge pins inserted into the holes of the lugs welded to the ends of the elements. Together they make up the outline of the cochlea.

To attach such a snail to the working base, you need to drill holes in it to fix it to the surface in a certain position. By changing the position of the prefabricated parts on the base, you can obtain different curvature of the curls and their shape. The size of the arc of the shape is regulated by special screws attached to the connecting hinges.

It is quite difficult to make a composite volute with hinged joints yourself. Typically, craftsmen purchase a stamp made in an industrial environment and attach it to the bed.

You can make a simpler collapsible template device yourself without using hinges. To do this, you need to make a sketch of the prefabricated parts of the snail with the locations of the holes. If you prepare several sketches and, in accordance with their contours, drill holes in the base in different places, then you can attach templates with different radii to one base. To do this, you will need to bolt the contour segments where the holes of the template and the base align.

For example, you can do this:

Step-by-step manufacturing of a small-sized manual machine for making curls

A small machine is designed for the production of curls from rolled strip with a width of 20...30 mm. It's easy to make it yourself.

Center

First the center is made. To do this, a small fragment of round timber is sawed off. The workpiece is fixed in a vice and the cutting line is marked. Using a cutting disc and an angle grinder, the workpiece is sawed off.

It has a diameter of 38 mm. The side surface is not further processed.

The center length is 28 mm. A little more is possible, but this is enough to bend a strip 30 mm wide.

A hole Ø 8 mm is drilled on a drilling machine. It is placed eccentrically. This situation is due to the fact that it is necessary to make a clamp for the end of the workpiece.

A profile is drawn, which should be removed using cutting and cleaning discs installed on the grinder. The workpiece is secured in a vice and excess metal is removed.

The flap discs protect the surface so that there is a smooth transition between different surfaces of the clamp.

To make it easier to fix the end of the workpiece in the future, you need to drill a hole. It is placed on the radial surface of the center. A hole is drilled for an M10 thread.

Using a set of taps, the internal thread is cut. A headless screw will be used here. After fixing the workpiece, it will hide inside the metal of the center.

The center is welded to the 4 mm thick base plate. This completes the work of its production.

Making a fixture

To make it easier to work with the device, a shaft is welded to the back side of the plate. By rotating it in a special mandrel, the snail will rotate.

The outer surface must be ground so that the welds do not interfere with the free fit of future workpieces.

The future spiral is drawn on the plate. A contour is created where it will be welded later.

A spiral is bent from a strip 4 mm thick. It must correspond to the project.

After checking the spiral against the template, the excess is cut off, and the spiral itself is welded to the plate and to the center.

A 40×40 mm profile pipe with a 3 mm wall is used as a stand. Holes are drilled on it for attaching machine elements. Using support platforms, the prepared parts are fixed.

The handle is visible on the reverse side. It was secured to the shaft using a bearing. The prepared “Snail” can rotate.

A performance check is being carried out. The handle turns the spiral around the center axis.

Other equipment: universal, templates, patterns, etc.

Cold forging fixtures are used for arc bending, angling or twisting. Below are the main types of equipment.

The machines also include:

Stamp press. Using this device, a certain pattern is applied to metal by printing it from templates under pressure.
Mechanical unit. A device that helps bend a rod into a circle shape with different diameters.
Forging devices, which include templates, mandrels, and jigs, are used by individual craftsmen who are not chasing the number of elements produced.
Hand tools: pliers, forks, heavy hammer or sledgehammer are also more often used by individual craftsmen.

For your information! Templates, jigs and patterns for cold forging can be varied; each master makes them independently to obtain an exclusive form of the material. The most common types are listed above; you can make them yourself at home.

Marking and installation of “attached” equipment

Perhaps the most creative stage of work. You can do everything with your own hands. But how, taking into account the future or limiting ourselves to the production of similar samples?

Option 1. The simplest. The meaning of the operation is that the outline of a spiral is drawn on the tabletop.

Essentially, this is a sketch of future shaped parts, for example, from a rod. After this, it is enough to cut out several segments from a thick strip of iron, bent along a radius. They are welded to the tabletop, and the bending mechanism is basically ready.

Some may find this design more attractive - with a solid stripe.

But practice shows that it is more difficult to work with such a snail. For example, when removing the finished product from it, certain difficulties will arise.

Option 2. The same, but several contours are drawn. Holes are drilled along each one and threads are cut into them. All that remains is to prepare the templates for the stop segments. They are usually made with your own hands from thick cardboard or plywood.

Overlays are made from metal, in which, after the next marking, holes are also drilled, coinciding with the landing “sockets” in the slab. This design will make it possible to organize the production of spiral-shaped workpieces with different radii on one table. You will only have to, depending on the shape of the bend, install the appropriate segments in certain places. Their fastening to the base is bolted. You can do it differently. Instead of such stops, install cylindrical ones.

For fixation, they are attached with bolts (from the bottom of the slab) or are made immediately with legs (+ thread) and screwed into the tabletop. It's much more convenient with them. And if you have your own mini-lathe, then turning it yourself will take a couple of hours.

Option 3. Prepare several removable modules that can be changed as needed.

Stamping, forging and bending

So what is cold forging? It differs from stamping in that the metal hardly flows or flows weakly under the influence of the working element. Take a look at a beer can or, say, an aluminum or tin kettle. They are extruded with one blow of the punch of the stamping press; kettle, etc. products of complex shape - with a composite sliding punch. It is impossible to obtain the working force necessary to create such a high pressure at home, except in one case, see below.

Cold forging differs from hot forging, of course, in that the workpiece is not preheated. Actually, cold forging, which is forging, is the hardening (hardening) of a part with a long series of regular blows of a certain force. In this case, the structure of the metal changes significantly: the hardness of the surface layer increases, and the core provides overall toughness and fracture strength. Handicraftsmen - toolmakers and gunsmiths - literally hunt for buffers and wheel tires of railway cars, pieces of rails.

Steel hardening is carried out with a mechanical hammer.
You can do it yourself, and it’s even easier than some types of machines for cold artistic forging. But this publication is devoted specifically to the latter subject, and cold artistic forging is essentially bending (bending) metal: its structure in the part does not undergo significant changes, and changes in the physical and mechanical properties of the metal are not significant for the quality of the final product. Therefore, let’s leave cold forging, which is forging, until a suitable opportunity, and let’s deal with forging, which is bending. For brevity, we will simply call it artistic forging, and where it is necessary to mention hot forging, this will be specially discussed.

Functionality check

This is always implied, so no comment.

In principle, making a snail for cold forging is not so difficult. Moreover, there is no single standard for such devices.

Someone will say – isn’t it easier to buy a factory model? Firstly, as already said, you will have to search for a long time. Secondly, it is not a fact that her capabilities will coincide with the fantasies of the master.

Thirdly, you will have to lighten your wallet by about 19,000 (manual) and 62,000 (electric model) rubles, at a minimum.

Good luck in making your own snail!

Step-by-step technological process for making a reverse curl on the “Snail” machine

The rolling rollers perform sequential crimping of the pipe. Protruding ribs are formed, and the weld remains inside the layer, offset to the center.

The pipe ends are compressed on parallel eccentric rollers. It becomes like a stripe. In this form it is easier to fix it on the machine.

The shank is formed in a special device. Now the workpieces will be fixed on the machine in one movement.

The workpiece is fixed in the center. There is a groove that secures the shank. It can be seen that the spiral has a uniform descent in height.

After fixing the shank, the electric motor is turned on. Forming of the part begins.

The loop is formed when the workpiece touches a special support element. It is more often called the support shaft. To reduce the force, it is equipped with a bearing. The part rotates freely around the support.

Part of the spiral is formed. But if it is necessary to process for a longer length, a removable element will be installed.

A blank is also formed from the other end. Here the master determines in which direction to bend the part.

To continue work, a removable element of the “Snail” assembly is installed.

Now you can form the bend of large parts.

Even long workpieces are easily bent to specified dimensions. Marks are made on the work items. They are used to guide how much to bend.

On the reverse side, additional bending of the part is performed.

The product is being finalized on both sides.

The finished part has a finished appearance. If necessary, the shanks will be sawed off. Then no one will guess how the workpieces were fixed.

If you need to make a small part, then use another “Snail”. Experienced craftsmen have several of them.

Creation of a machine

The manufacturing process of the machine has several stages, after completing which one after another, you will receive a ready-made tool with which you can create figured products for your dacha or home.

Before you start cold forging, you need to make a template and drawing. It is performed on graph paper, which can reflect the exact dimensions of the future product. On it you need to depict a spiral with increasing turns.

The turns should increase in accordance with the pitch if you want to make symmetrical products, but if this is not important, then the spiral turns may increase unevenly.

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Before assembling the machine, you need to decide on the diameter of the workpieces that you will process on it. The step must be selected based on this value: it must be larger than the diameter of the rod that you will be processing.

If the step is not large enough, then you simply will not be able to remove the parts from the machine without damaging it. Thus, all the work will be done in vain.

A homemade working surface of the snail can be made of sheet metal with a thickness of 4 mm. The size of the surface depends on the size of the part you will be processing - you need to first draw up a drawing so that all dimensions are clear.

To make the mold, use strip metal that is at least 3mm thick. This way, the homemade snail will be easy to work with. To make the process easier, you need to fix one of the edges of the workpiece so that it does not slip out.

Sketch of a machine for a snail: Figure 1: 1- driving share of the snail, 2 - main axis, 3 - levers for applying force, 4 - clamp for the workpiece; Figure 2: 1 - volute share, 2 - machine platform, 3 - pressure roller, 4 - lever for controlling the pressure roller, 5 - fastening of the platform, 6 - finger for fixing the volute shares, 7 - groove along which the pressure roller runs, 8 - axis of the pressure roller control lever, 9 - spring for attracting the roller; Figure 3 - operating principle of the device: 1 - the snail rotates; Figure 4 - examples of products made using a snail.

For the retainer, you can use a cut rod part that is the same size as the strip. During cold forging, you also need to attach the part to the workbench.

Since during cold forging the impact on the part is quite strong, you need to think about fixing separately, because You won’t be able to hold the workpiece with your own hands - it can slip and ruin the whole job.

The remaining parts of the snail are quite easy to assemble - the main thing is to use the drawing and watch the video before starting the process yourself.

The machine you make can be either monolithic or collapsible - decide in advance which design will be more convenient for you, and make a drawing to carry out all the work in accordance with it.

If you want your homemade snail to be monolithic, then weld the machine onto the work platform so that the elements are stationary.

The most important thing with this type of construction is to correctly and securely fasten the end of the part that you will be processing.

If the machine for cold forging is planned to be dismountable, then landing holes must be made on the working platform, with the help of which it will be possible to connect the “body” of the machine with the platform.

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The removable design is good because it is more convenient to move it, if necessary, or remove the machine to replace or repair damaged parts - with a monolithic type of structure this will not be possible.

However, with a removable machine, the quality of fixing parts will be worse - you will have to constantly adjust the threaded connections yourself, because with use they will inevitably become weaker.

There are other options for machines for cold forging, but the “Snail” machine is the most functional, and besides, it’s easy to make it yourself. How to make it, as well as other product options, watch the video.

Video:

If you decide to use a snail as a hobby tool, you should take into account that, although the device itself will not cost you much (it does not require any specific parts or tools), cold forging still involves some expenses.

Firstly, you will have to spend money on the materials themselves that you will process. And the larger the product is planned, the more money you will have to spend.

To estimate costs, always make a preliminary drawing of the product, which reflects its actual dimensions. For example, to make a small flower stand, you will need to spend at least 2,000 rubles on rods.

You can calculate how much material more complex products will require yourself.

The cost will also depend on the complexity of the pattern that you will create with the help of a snail - the more complex it is, the more expensive the product will cost you.

You won’t have to spend a lot of money on tools for the machine itself, however, if you have not previously made such tools, then it is better to buy ready-made equipment for it - in this case, the machine will last you longer and it will be easier to work on it.

For final processing after forging, you may also need some funds - at a minimum, you will have to buy a primer and paint to give the part a finished, attractive look.

Despite these expenses, snail forging is still an affordable and popular metalworking tool that can be done as a hobby or on a professional basis, but in this case, over time you may need a more powerful tool.

Video:

Types of machines

The parameters, setup variations, and manufacturing aspects of the equipment vary widely. Based on their identification, designated classes are formed. It is worth understanding that only some of them are available for amateur production, the rest function only in factory conditions.

Torsion bar

This is an analogue of the previous type of equipment, but based on an I-beam and a clamp. In the center there are vise rollers that pass the structure through themselves. The twisting is stronger and more intense. However, not all categories of products can be processed using the indicated method. For example, hollow and round products will not withstand pressure and will be incorrectly deformed.

Machine "Gnutik"

This is a simple DIY cold forging machine. It consists of two shafts, which in a certain way press the part passing through the middle. They are mounted on a static surface, and a wedge is placed in the center. Its task is to make a depression when the shafts begin to move.

Machine "Volna"

Often this manufacturing method is used in production. Therefore, such devices are often purchased in specialized stores, rather than created using artisanal methods. But there is nothing complicated about this either.

You will need a metal flat base and a couple of disks. By passing the material through themselves, they create that same wave on it. One of the disks will be the master, the second remains passive. That is, movements are carried out only by the first element. However, they do not have to be identical in size.

Press

This type of equipment is suitable if you are making flat objects. In fact, these are just two shafts that press the part together, without adding grooves or recesses. In this case, the product can still be made non-uniformly flat if the shafts themselves are corrugated. In this case, the gap between them is slightly increased so that they do not get into each other’s threads.