Homemade crossbow with your own hands. Making a crossbow with your own hands is not as difficult as it seems. What wood to use

If you don’t want to buy an expensive crossbow (and prices sometimes exceed $1000), you can make a crossbow with your own hands. It's not as difficult as it seems at first glance. The design of the crossbow is quite simple. A crossbow can be made from what is at hand, replacing missing materials with similar ones. A homemade crossbow is quite suitable for target shooting.

General view of a crossbow that you can make with your own hands according to drawings

The design of this crossbow uses the developments of manufacturers in the field of weapons. The drawings show a crossbow of a block design. If you follow the instructions and observe all the dimensions, you can make a high-quality and good crossbow with your own hands, even at home

General diagram of a homemade crossbow assembly:

To begin with, it is advisable to carefully study the drawings of the crossbow and begin assembling it yourself. Making a crossbow with your own hands is not an easy task. But this increases interest in work! After all, a homemade crossbow can bring great joy and respect to the performer.

Crossbow structure: stock, shoulders, butt, trigger mechanism, sighting devices, block system. To make the stock, natural wood, solid or laminated timber, mainly hardwood, is used. The exact dimensions of the crossbow can be seen in the drawings. You choose the shape of the crossbow yourself, guided by the convenience and ergonomics of the stock and the desired image. When choosing, you must also consider whether you can make such a form correctly.

Crossbow shoulders and deck drawing:

The use of a small arms stock can significantly reduce labor costs for the manufacture of a crossbow. The main thing is to choose the right size. The trace of the trunk left in such a stock must be hammered in with wooden blocks, firmly seated with epoxy glue. The butt and under-barrel pad of a crossbow can also be made of wood. The stock will be attached to the guide and serve as the basis for the trigger mechanism.

Butt drawing:

Offered for DIY assembly, the crossbow has a block design. This allows you to compensate for the load when cocking the bowstring and maintain power. Compound crossbows are the most popular among hunters because... You can carry a crossbow in a cocked state for quite a long time. Horton actively uses this design in the production of its crossbows.

Drawing of block assembly parts:

Pay special attention to the processing of the arrow guides and bowstring. The clarity of their finish greatly influences shooting accuracy. The guide lines must be perfectly straight and smooth. The best choice would be grinding on a milling machine and subsequent processing with fine-grain sandpaper. Next comes polishing the guides. You can see the dimensions of the boom guide groove in the drawings. The crosspiece, with the shoulders attached to it, is installed at the end of the stock. It is usually made from an aluminum billet. Wood can also serve as a suitable material.

A crossbow sight must consist of a rear sight and a front sight. You can also install an optical sight on the crossbow, providing a mount for the aiming bar. Vertical adjustments are made entirely, mounted on the cover of the trigger mechanism, and horizontal ones - with a front sight mounted on the bracket of the elastic element.

There can be many design options for sights and sighting devices for a crossbow, depending on the possibility of manufacturing, the availability of ready-made sights from conventional weapons (air rifles), etc.

It should be borne in mind that the flight path of a crossbow arrow (crossbow bolt) is quite high, so the rear sight must be installed significantly higher than the front sight. The angle of elevation of the aiming line depends on the weight of the arrow, the tension of the string, the shooting distance, etc. In our crossbow at a distance of 50 m it is approximately 6°.

Convenient are the designs of the rear sight, which allow it to be removed or folded during transportation. It will also be convenient if the rear sight can be adjusted manually by raising or lowering the bar. Thus, you will be able to target the crossbow under different conditions (distance to target, weight of the arrow).

The crossbow, the manufacture of which is described above, is designed for shooting bolts with a diameter of 8 mm and a length of 450-470 mm. You can easily make them yourself from a duralumin tube with a wall thickness of 0.5 mm. The tip and liner are attached to the bolt in front, and the feathering is attached to the back, just as they do for archery. It should be borne in mind that the shank of a bolt for a crossbow, unlike an arrow for a bow, should not have a cutout for the bowstring; it should be flat. It can be carved from wood in the form of a cork and inserted into the end of the tube, having previously been lubricated with glue.

A must read!

Making homemade weapons, in particular crossbows and bows, less often knives, are practiced, as a rule, by teenagers and young people up to twenty, twenty-three years old. Older people prefer buy branded factory-made weapons. However, there are exceptions.

For example, an older person may be keen self-made weapons at the hobby and collecting level. But most often his passion is to become closer to professional work, since it is not a one-time impulse. According to statistics, this site is visited mainly by young people from fourteen to twenty-eight years old (according to Yandex metrics). They are mainly interested in methods and methods for making any homemade weapons.

However, with an unprofessional attitude towards the subject of interest and a lack of technical skills, creating homemade products can lead to unwanted traumatic situations that can harm the health and even, in some cases, the lives of young experimenters. Therefore, if you are interested in the idea, by all means purchase one of types of permitted weapons, then it is better to buy it in a store, or contact a qualified specialist. Of course, in this case certain costs will be required, but they are not as critical as it seems at first glance. That is, your health is much more valuable than a certain amount of money spent on purchasing, for example, a crossbow.

Naturally, not all young people have available funds for the purchase of weapons, and not everyone has the right to use it, even if it belongs to the category of sports, due to their age. Therefore, in specialized stores it can only be sold to a person who has reached the age of majority and has the appropriate document permitting the purchase and use of weapons for personal purposes.

Otherwise it will be the case with online weapons stores, for which it does not matter to whom the weapons are sent, and all surveys during registration are formal. But as mentioned above, teenagers under eighteen years of age rarely have their own income and therefore in most cases sporting weapon acquired with the knowledge of the parents and with their direct participation.

More details for fans of ready-made stock drawings

Please note that the crossbow is made from a bow. That is, whatever bow there is, the crossbow will be adjusted to its parameters, because each bow has its own unique parameters - tension force, length of draw stroke, length of arms finally. Further, the lock also meets the specified requirements, it has its own geometry and it may not always be suitable for the desired type of stock. So there is no point in such drawings and they can only be considered as an illustration for understanding the general principle of the arrangement of parts.

Some features of the manufacture of crossbow stocks deserve closer attention, allowing you to save material and nerves. When making a stock for a compound bow, please note that the groove in it for the intersecting sections of the bowstring must be extended towards the lock, since when tensioned, the ends of the bow with the blocks are bent back. Sometimes an incorrect cut forces a radical change in the location of the nodes, which entails a change in the design of the product as a whole, sometimes not for the better. Don't forget to leave at least a millimeter in reserve. By milling you can only set the initial shape, for example, of a key groove, and finalize it with the help of a small chisel and files with needle files.

A quick note about stock finishing

The question is often asked about where to get drawings of a stock; a stock can be made even from a chair leg, but the crossbow itself ultimately should not be just a constructor made of ridiculous parts, but should be a product made in the same style. For example, crossbows in the medieval style with a powerful bow, forged fittings, a rigid lock and a rough wooden stock look holistic and balanced; or a light and elegant sports crossbow with optics, a thin and sharp bow, and an anatomical stock; not to mention futuristic crossbows with polished metal surfaces, a laser designator, a cast titanium stock and an ultra-complex lock. In other words, the final finish depends on your taste, but do not forget that it will be judged by your crossbow.

More about guides

High-quality guides are the most important element affecting shooting accuracy, as they establish the initial orientation of the bolt (arrow). They can be made from any material, preferably with a low coefficient of friction. Although the guides carry virtually no load, they must have sufficient strength to maintain straightness. Therefore, it is a good idea to make them as a separate part, attached to the stock at points at its ends. This makes it possible to easily change it if necessary, for example, in case of damage or switching to another type of bolts; moreover, such fasteners allow you to “untie” the guides from the deformable stock. The longitudinal guide groove for the bolt usually has a depth of one third of the diameter of the shaft so that the plane of the bowstring coincides with the axis of the bolt. It is convenient when a narrow groove for the lower tail passes through the guide, then random needles when shooting in the forest, for example, will not interfere with the movement of the bolt.

As already mentioned, it is convenient to make the guides separately from the stock. The material can be metal, plastic or wood. The required thin longitudinal groove can be made with a thin jigsaw blade or by making a guide of two halves, which is also very convenient and has its advantages. A particularly important factor in manufacturing is maintaining absolute straightness and parallelism. Naturally, you will have to apply sandpaper or a hairy polishing wheel. The dimensions are not at all critical and are determined only by the length of the stock section from the block to the lock, corresponding to the running (landing) part of the bolt, as well as the diameter of the bolt shaft and the type of its fletching. The bolt should fit freely, but without play, into the guide groove; the feathering should not touch anything. The guides are installed in such a way that the axis of the inserted bolt coincides in the front part with the position of the string fastening (! nuance) on the bow, and in the rear part it passes through the filling cutout of the lock. The nuance is that the front part of the guide should be slightly higher than the specified plane, which ensures some sliding of the bowstring pushing the bolt. Naturally, everything should be within reasonable limits, and the wooden surface of the guide must be protected from abrasion by the bowstring with additional metal pads.

Lock

A lock made from a clothespin and a tin plate hardly deserves any attention. The crossbow lock is a very important part. There is an opinion that the simpler the lock, the more reliable it is, but I would interpret it somewhat differently - the better the quality of the lock, the more reliable it is. The manufacture of the lock must be treated with special attention, because convenience and reliability, as well as the clarity of operation, and therefore the accuracy of shooting, depend on its operation. A little about the functions of the lock. A good lock should ensure guaranteed retention of the bowstring on an equipped crossbow, as well as a clear release at the required moment of aiming. It is in accordance with the first point that additional blockers and fuses are introduced into the design of locks, and with the second, intermediate unloading levers and repeaters are introduced. The choice of lock design again depends on your locksmith capabilities and needs, and here you can exercise your creative inclinations to your heart’s content in upgrading existing models and developing your own. Personally, I liked the design of professional locks presented on one of the sites. The bicycle has been invented, but has it been invented yet?

To make it easier to embed the lock, it is necessary to try to give it the simplest possible shape when designing it. That is, locks with various cavities are unlikely to be neatly packed into the stock, while flat, rectangular locks in this regard do not cause any special problems when cutting into the stock. It is important to take into account that the locks must be securely fastened, without backlash, and have a maximum area of ​​contact with the stock to relieve the load. What is often not taken into account is the simple fact that the lock bears the entire tension load. That is, if you are making a crossbow with a bow weighing 300 kg (probably for an elephant), then the parts of the castle will naturally receive all 300 kg of them + shock load and so on, but the stock should be able to handle it in its thinnest place (usually where it is weakened by the key groove), still survive 300 kg + torsion and other non-parallel loads. Again, in some drawings, the locks have attachment points too close to the edges or small diameter holes for thin bolts or screws. If this value turns out to be acceptable for metal, then for wood it is necessary to provide some reserve. So, summing up all the factors, we can conclude that the lock must have minimum dimensions, in particular width, have a maximum surface of contact with the groove, that is, fit its front surface tightly in the groove, and only be fixed to the stock with bolts. In addition, the stock itself must have sufficient strength in its weakest part when calculating the bow's tension load. So for monsters, it’s better to make a stock from a metal profile, and put linings made of beautiful durable wood on the body kit. I cannot give any special recommendations regarding the choice of wood due to my incompetence on this issue, although I personally prefer beech.

For those who do not live in the regions where this wonderful tree grows, I advise you to pay close attention to the old pianos of your acquaintances and friends. In them, beech is found in the form of massive power beams for hanging cast iron frames. At the risk of arousing the wrath of aesthetes, a piano these days is easier to find than a piece of good wood. Let's write off this barbarity as a by-product of art. For metal lovers. Excellent aluminum and alloy profiles can be found in office furniture. Rigid rectangular profiles are now commonly used in some machine tools. There is a wonderful thin-walled pipe made of blackened metal in.... a large inclined tablet like that of designers or draftsmen. I don’t know what the warriors have to do with it, but such a pipe can be used in powerful pneumatic and light firearms systems, as well as for fireworks mortars. You can also cast stocks from aluminum and alloys, followed by milling grooves and other things, but this is more a matter of technology and taste.

Let me remind you that the tension force of the bow acts on the lock! This means that the lock must withstand heavy loads without loss of functionality, so tin as a material is immediately excluded. The proposed millimeter steel, after processing is already 0.8 mm, can only be used on crossbows of small power, otherwise the lock will simply be deformed. The details of the castle are also worth taking a closer look at. The main hitch is under full load, so use stronger steel and a thicker axle. Depending on the design and lever, a lesser force acts on the release that releases the hook. Other parts can be made based on their purpose and the load on them, without forgetting the margin of safety and wear resistance. Gunsmith designers have a technology for constructing the mechanisms of real weapon locks “on pins and needles”, this is when the contours of the intended parts of the lock are cut out of cardboard, pinned at the points of their axes to the plywood. At the same time, it is possible to immediately see the interaction of parts with each other, correct them, and then translate everything into metal. In principle, all that remains is to choose a suitable lock; further modernization can be achieved by using high-quality steel, some modification of the trigger and equipping the lock with additional devices, adjustments, etc.

Structurally, locks with a so-called “nut” or a similar hook design are more suitable for crossbow sniping. The hook rotates freely on an axis close to the center of mass, resulting in a very soft, jerk-free descent. Such locks will appeal to lovers of high-precision shooting and the fairer sex (there are such in this business!), but the Hollywood-style clanging and clicking aggressive locks will be more useful in systems of a threatening militaristic or medieval style of execution. In one of the “pro” locks, the design of which I took as the basis for mine, there is a safety lock and a lock that prevents the bowstring from being lowered without a threaded bolt, which is quite thoughtful for preserving the bowstring. By adding a slot in the upper part of the hook, it was possible to ensure shockless interaction of the bowstring on the butt, the rear end of the bolt, in common parlance, the “butt”.

Block

Designed for attaching a bow or its limbs directly to the stock. The block works under very intense conditions and experiences shock loads, so it must have a significant margin of safety. Made from aluminum casting or metal, calculated depending on the bow used. The block for separate bow limbs is subject to more forces with different vectors. When designing pads, it is necessary to wisely use various bevels and triangles, which allows for significant savings in weight with the same rigidity of the part. The block can be removable to reduce the size of the crossbow when carrying. There is a certain peculiarity in the method of attaching the bow limbs to the block, which is that it is preferable to use threaded clamps rather than rivets, but it is better not to weaken the bow limbs with holes at all. (!) Pay special attention to the fastening of the bow limbs, take into account the rule of leverage, which, together with the tension force of the bow, adds up to an immodest amount. It is most convenient to make a block from thick sheet steel, bending the workpiece like origami.

The bow is the main part of any crossbow

Structurally, it is easier to use a monobow made of durable and elastic steel, but some plastics are also suitable. The simplest thing is to use ready-made bows for sports shooting. Can be made from any elastic spring steel, such as springs. We used a powerful spring from some relict hell trap. A compound bow, consisting of a package of strips, has enormous friction losses between the strips. Even if you lubricate the stripes with something like “ER” to reduce friction, using such a bow is not advisable. If you want to make a removable bow with latches, then I advise you to secure the bow tightly to the block, but the block itself can be made tightly fastened to the stock. In general, analyzing the physics of a bow, it can be noted that a bow with developed shoulders, which have some narrowing towards the ends, is better. Such a bow, bending evenly, accumulates a lot of energy. However, larger bows require a longer stock due to the increased draw stroke, which is unacceptable. Ancient crossbows, judging by the sources, fired at 200 steps. So they “beat”, knocking the riders off their horses, but for a longer firing range you already need perfect sights, and even now no one shoots from machine guns at a longer range, there is no point. We'll talk more about firing range in the paragraph about bolts.

If possible, you can forge a bow from a suitable metal, and it is better to immediately provide places for fastening the string on the block. Again, it is better to make a block pattern if the bow has a lot of power.

The block brackets, the blocks themselves, work on the tension force of the bow + the compression force of the bowstring + shock loads. Blocks can be machined from a material suitable for strength, but it is necessary to relieve the bow's arms as much as possible. In most cases, the choice of aluminum as a block material is very successful. For those who have difficulty making blocks, I recommend looking into old reel-to-reel tape recorders. In some models there are wonderful blanks for aluminum alloy blocks; you just need to cut off the excess. To lighten the blocks, holes are drilled in them or windows are cut out. You can also look into old receivers, where the venier is based on a cable system. The warriors have a lot of old radio equipment with such units. There are small blocks on ancient dental burstanki. On professional crossbows, the blocks are oval-shaped. This is due to the fact that the block rotates only at a small angle. I think that the fact of some gain when using a block scheme versus a conventional, recursive one is obvious, but a further increase in the number of blocks gives less and less results. So there is no point in assembling a garland of 6,8,10 blocks. Even a child can draw a four-block crossbow. I note that a compound bow works more softly than a recurve bow, which improves shooting accuracy, and besides, the force to break the string is less, apparently due to the loading of the string with blocks.

Springs are sometimes used as a propellant on some exotic models, but they have a large weight, volume, short stroke and enormous energy, which in turn entails a more complex design and requires high-quality steel for locks. A compressed car shock absorber spring can easily tear off a person's arm or leg. A shot from such a spring into a bag of compacted cement pierced it, and the spring itself flew off behind a row of neighboring garages. A very dangerous and inconvenient thing.

Bolt - crossbow arrow

The bolt is the damaging element of this type of weapon. It has a greater (emphasis on the first syllable) stopping effect than a bullet(!). Kevlar body armor also loses its effectiveness against such hello from the Middle Ages. So it would be appropriate to once again remind you of compliance with safety rules when shooting from a crossbow, despite the fact that the article is devoted to a slightly different topic. A bolt wound can often be fatal! The death of a victim can even be caused by just the sight of a bolt protruding from the body!

So, bolts. They are made from any durable material that is lightweight and has sufficient elasticity. It can be made from suitable pieces of straight-layered wood, and the layers of wood should be arranged longitudinally, which gives the arrow flexibility. It’s difficult to do without some mechanization in the form of at least an electric drill. The bolt must have a perfect shape, the center of gravity is usually located between the first and second third of the bolt, and already assembled (!), however, it is possible to vary this parameter at your discretion. You can change the mass of the bolt by selecting different materials for the shaft, sizes and materials of tips and toes. To protect against moisture, wooden bolt shafts are impregnated with protective compounds and are usually stored in a horizontal position. Great bolts can be made from sections of broken fiberglass telescopic fishing rods. They have great strength with low weight and are not afraid of dampness. Please note that all bolts should be as close as possible in weight and size, otherwise a surprise will await you with each new shot, especially when shooting at maximum range. In general, the crossbow itself allows you to shoot quite heavy arrows, even with welding electrodes, so it is quite difficult to clearly determine the optimal bolt. When selecting experimentally the mass of bolts for your crossbow, do not forget about the golden mean: a light bolt loses speed faster, and a heavy bolt does not fly far. Instructions for making bolts yourself -.

About the firing range

A crossbow is a crossbow. A bolt, like an arrow, is launched with a relatively low initial speed, has a fairly high air resistance and a small mass, so that physically it cannot fly very far, one must be realistic. There are firearms for such things. By the way, looking back to ancient times, the crossbow was valued precisely because it was used exclusively for the destruction of heavy cavalry at medium distances, having a short and heavy arrow in its arsenal. I consider articles that mention shooting almost a kilometer away to be purely humorous.

Bolt ends are made based on the task at hand for this type. Hunting bolts are generally equipped with creepy-looking four- or three-bladed harpoon-like tips. Almost any hard material can be used for sports shooting. When shooting at hard targets, bolts often break. It is better to make the tips with a recess for mounting on the bolt shaft. Tips attached to the cut of the shaft usually split it when it hits a solid obstacle. Rubber tips don't make sense. The diameter of the tip may exceed the diameter of the bolt if the shaft is longer than the guide.

Bowstring

A good bowstring with proper care will last a long time. It is made of steel (cables, strings), polymer wood or woven from silk. I don’t know about the latter, there are now a huge amount of synthetic materials. Kevlar for making a bowstring should be used as a material with high tensile strength. For powerful crossbows, you can use a thin steel cable for the bowstring. Found everywhere in motorcycles and automobiles. I note that a braided bowstring can more easily withstand breaking loads due to the fact that part of the energy is spent on friction between the woven threads. Protect the bowstring from abrasion on the stock with special metal or plastic pads.

Sights

Actually, it's a matter of your taste. The use of certain sights depends on the range and nature of the crossbow's shooting. Optical sights for weapons at a hundred meters or less are generally somehow ridiculous, although a crossbow with optics looks quite predatory. They have a large mass and prohibitive cost, require a standard mounting bar, and are convenient for shooting at a static target. Installing collimator sights in this case is more justified, and it also becomes possible to shoot offhand. Even simpler and better for crossbows are simple diopter sights, and the simplest open sight is not difficult to make at all. I’ll keep silent about optics for now, but you can stop at making open or diopter sights. The fact is that there is some difference between the axis of flight of the bolt and the axis of the crossbow, not to mention the hinged flight path of the arrow, so for sights it is necessary to provide for the possibility of fine adjustment using the appropriate screws. To do this, the mounting of sighting devices is done with oval holes that allow some displacement, or adjusting screws with fine threads are installed in the body of the mounts, which shift the sight itself when rotated. It is best to zero in sights indoors or in calm weather. In this case, the crossbow itself is fixed on a massive fixed base, for example, with clamps. Next, test shots are made with one standard arrow. The difference between the aiming point and the actual point of impact of the bolt at a given distance is adjusted using the adjusting screws of the sight. Then the shooting distance changes and the process repeats. This way you can calibrate any sight for any shooting distance. Corrections for wind are entered in the same way (frontal against the wind, at an angle towards, at an angle downwind, at a side, downwind).

Tensioner devices, such as various “goat legs”, can easily be made from a suitable metal, changing the dimensions of the data to fit the geometry of your own crossbow, however, such devices are rather necessary for cocking very powerful crossbows with recurve bows or are simply a convenient excess, since compound bows are even of considerable power can be cocked by hand, albeit with gloves.

This completes the theoretical part of the instructions on how to make a crossbow, see the photo and explanations below:

To make a crossbow we need a wooden stick and a piece of iron

The stick is made approximately according to these dimensions

One spring plate 650Х100Х8 was taken. Using a grinder, we slowly separate out what we need. The dimensions of the arch in the middle are 35 mm, and at the edges - 18 mm.

Using sandpaper, we narrow the shoulders, evenly from the center to the ends until we reach 5 mm. in thickness. We stretch a steel wire (cable) onto the arch in this form. We clamp it in a vice. We will insert a round timber strictly in the center so that it does not interfere with the arch when bending. We tighten and at the same time check the force and tension distance. We will dance from these parameters in the future.

As in “The Golden Calf”: we take a weight and saw. And this is what happened. The most important part in a crossbow. Hook or crampon.

But to make a normal lock, we need a sear and a trigger. A hole is made in the upper part of the pin so that the bolt of the strip spring falls into this hole and fixes the pin from moving.

Let's start making the lock body

We carefully try everything on and drill holes for the pins.

Let's start making the trigger guard. We take a wooden stick and try it on.

Hollowing out a place for a lock

Inserting the lock

To attach the rear sight we make a dovetail. And solder it. I did it with PSR, but it can also be done with POS. It all depends on how we will burnish (what temperature it will be).

In the arch we drill two holes at the edges for attaching clamps. Many people ask whether it is possible to drill a spring. I answer - freely. Pobeditov drill corrected on a diamond wheel.

Grinding the rollers

Grinding the rollers

We adjust the clamps to the required size. Let's start making the arch mounting clamp.

Making a stirrup

This is how I seal the ends of the string. Do not hit, but press with a lathe chuck.

In production and finished form

Finished look

Let's begin a very serious operation - bluing. I specifically show the unsuccessful bluing.

Here's some successful bluing

Take a stick and make a channel for the guide

Glue the plank

Now let's take the butt, but be careful with the tools

We remove unnecessary things. The stick I took is a wild cherry. Birch, walnut, etc. are suitable.

Varnishing. But here who gives preference to which varnish.

Excess. But, in my opinion, it is pleasing to the eye.

It is important that the gap between the bowstring and the stock is 2 mm. The calculation is simple - the middle of the bolt diameter.

Bottom view

And I put shrink film on the arch. And it gives the appearance and protects it from fragments in the event of an arch breakage.

Finished look

After 40-50 shots the bowstring burst.

I decided to add 2 more videos.

To facilitate the design, the rollers were replaced with caprolon ones. With a distance of 30 cm from the string to the hook and a force of 85 kg. with the addition of rollers, the force on the arch decreases and the speed of the arrow increases.

Source cazac.ucoz.com

Another selection - professional drawings of a homemade block crossbow (download for free)

To view in full size, click on the picture.

Shooting, as a form of sport and an ability for self-realization, has enjoyed success among people for a long time. An indication of this is the countless competitions using various types of weapons. One of the oldest types is throwing weapons. The heightened emotionality of these days resonates in archery and crossbow tournaments.

Sports crossbow shooting in our country is not as developed as bow shooting. This state of affairs is not due to a lack of interest, but to an obvious shortage of shooting equipment. Crossbow sport itself certainly contains many advantages. Today we suggest making a crossbow with your own hands. It will be a wide field for the discovery and application of certain types of talents.

DIY crossbow made of wood

As a way out, you should make a crossbow with your own hands. This is not as problematic as it might seem at first glance. The design of the crossbow is light. In sections of bullet or bow shooting, there are weapons workshops where it is easy to find professional craftsmen. Such a specialist has the right to make a crossbow from whatever he has on hand, replacing missing building materials with identical ones. A homemade crossbow is sufficient for target shooting.

We drew a drawing of a crossbow and assembled it with our own hands. When creating the crossbow, the developments of foreign manufacturers and fellow athletes who themselves make crossbows without the help of specialized companies were taken into account.

Our crossbow differs in that we chose bow limbs as the elastic component. This selection is justified by the lighter weight, in contrast to steel shoulders. Plastic shoulders also even out physical contact from powerful recoil. To gain the ability to shoot accurately at distances of up to 60 meters, all you need to do is tighten these arms without applying much force. The ability to use limbs from broken bows is another positive feature of our device. The main thing is to find a pair based on strength. We advise you to carefully study the crossbow drawings and begin assembly. To create a crossbow is not to cross the field. Read on to learn how to make a crossbow with your own hands.

Crossbow device: stock, shoulders, trigger mechanism, sighting devices.

To create the bed, real wood is used, solid or glued, mostly hardwood. Approximate dimensions can be seen in the pictures. (1 and 3)- crossbow drawing. We choose the shape of the hands ourselves, guided by the convenience and ergonomics of the stock and the desired image. When choosing, you must also take into account the possibility of correct manufacturing.

Using a small arms stock makes it possible to significantly reduce energy costs for making a crossbow. The trace of the trunk left in such a stock must be hammered in with wooden blocks, firmly seated with epoxy glue.

The processing of the arrow guides and bowstring deserves special attention. Their finishing is quite dependent on the accuracy of the hit. The guide lines must be immaculately straight and smooth. The desired option is grinding on a milling machine and subsequent processing with fine-grain sandpaper. Then the guides need to be polished. It is possible to study the proportions of the guide groove for an arrow with a diameter of 8 mm at rice. 3. The crosspiece, with the shoulders attached to it, is mounted at the end of the stock. As a rule, it is cast from an aluminum alloy, but it is also possible to create it from an aluminum blank. Wood can also serve as a suitable material.

The window from which the crossbow arrow will fly must be located opposite the groove that guides it. This is exactly how the window must be located on the bed of the cross containing elastic elements. In this case, at the moment of departure, the bowstring can be pressed against the smooth plane of the stock. Each arm is attached to the crosspiece using 2 M8 screws. The mechanism for triggering the trigger device was created in accordance with the description of the design of crossbows of the Middle Ages. It can be done without any special problems even with an average level of illumination in the workshop.

DIY crossbow trigger mechanism

How this mechanism is structured and works becomes clear from Figure 4- DIY crossbow diagram.

When the bowstring 1 is cocked, it is engaged with the protrusion a of the lever 2. When the lever rotates, it holds the trigger 3. When the hook is pressed, at the same time the lever is released, at this moment the bowstring, straightening, sends an arrow. The stop 4 is limited during the movement of the lever. In order to soften the impact force on the stop, it is necessary to put a rubber tube on it. The stop must be in a position in which the extreme position of the protrusion a of the lever is lower than the guide surface of the stock. This prevents the string from sliding. After the shot is fired, spring 5 holds the lever in its extreme position.

In the process of pulling the crossbow, the bowstring is focused on protrusion 6, lever 2 takes its original position. Spring 6 acts on the trigger so that it rotates, the lever and the bowstring are fixed. To prevent the string from accidentally jumping off protrusion a, the release mechanism is closed with a cover 7. A flat-type spring 8 is attached to this cover, which holds the arrow on the guides while aiming the sight. Bearing 9, which is attached to the tip of the trigger, sufficiently weakens the force of the trigger. The level of trigger force is selected by sawing the surface resting on the lever bearing 2. In order to reduce the weight of the lever, it is better to make it from light alloy D16T. Safety pins can serve as a replacement for springs 5 ​​and 6. The trigger mechanism can be mounted in a metal housing, after which it is inserted into the stock socket and secured with two screws. In this way, reliability and ease of adjustment can be significantly increased. But this method makes the design more complex, and metal-cutting machines will also be needed to implement it.

The sighting device of a crossbow consists of a rear sight and a front sight. Vertical adjustments are made entirely, mounted on the cover of the trigger mechanism, and horizontal ones - by a front sight mounted on the bracket of the elastic element.

There can be many design options for these devices, depending on the possibility of manufacturing, the availability of ready-made sights for sports bullet weapons, etc.

It should be borne in mind that the flight path of a crossbow arrow is quite high, so the rear sight must be installed significantly higher than the front sight. Angle of elevation of the aiming line ( cm. Figure 1 - crossbow drawings) depends on the weight of the arrow, the tension of the bowstring, the shooting distance, etc. In our crossbow at a distance of 50 m it is approximately 6°.

The design of the crossbow rear sight is convenient, allowing it to be removed or folded during transportation.

Our homemade crossbow, the manufacture of which is described above, is designed to shoot crossbow arrows with a diameter of 8 mm and a length of 350 mm. Arrows for a crossbow can be easily made from a duralumin (D16T alloy) tube with a wall thickness of 0.5 mm. The arrow is equipped with a tip and fletching in the same way as is done for archery. It should be borne in mind that the shank of an arrow for a crossbow, unlike an arrow for a bow, should not have a cutout for the bowstring. It is convenient to carve it out of wood in the form of a cork and insert it into the end of the tube using glue.

In conclusion, I would like to express the hope that you understand how to make a crossbow; making it yourself will give you a lot of pleasure, and shooting from it will give you the opportunity to have a good time in the fresh air. Just do not forget that a crossbow, like any weapon, requires a responsible attitude and compliance with all safety measures when shooting. And the amount of pleasure directly depends on how the crossbow is made.

Crossbow Arrows (Bolt)

The striking element of a crossbow is considered to be a bolt. It has even greater stopping power than an arrow. Even Kevlar vests lose their effectiveness against this seemingly simple medieval weapon. That is why you should not forget to follow safety rules when shooting from a crossbow. Even though the article is about something else, it is very appropriate to remind you of the rules. In most cases, a bolt wound is fatal. Even the sight of a bolt protruding from the body can cause the death of a victim.

To make the bolt, a durable material is used, which is characterized by sufficient elasticity and low weight. The bolt is also made from straight-grained wood, that is, from suitable blanks. A prerequisite for the flexibility of the boom is the longitudinal arrangement of the layers of wood. In order for there to be small mechanization, you need to use, for example, an electric drill. The bolt must have a perfect shape.

The center of gravity is between the second and first thirds of the bolt. And this, mind you, is already assembled. True, the parameter can be changed at your personal discretion. Also, due to the different materials used for the shaft, the sizes and materials of the toes and tips, the weight of the bolt can be changed.

To protect wooden shafts of bolts from moisture, they are impregnated with special protective compounds and also stored in a horizontal position.

The best bolts are made from broken telescopic fishing rods (from their sections) made of fiberglass. They weigh relatively little and at the same time are very durable, and they are also not afraid of dampness.

To shoot from a crossbow, you can use fairly heavy arrows, even welding electrodes. That is why clearly defining the optimal bolt is a serious matter. In the process of selecting the required mass of bolts for your crossbow, it is worth remembering the golden mean: if the bolt is heavy, it does not fly far, but if it is light, it loses speed quite quickly.

If the bowstring is of high quality and you take good care of it, you will use it for a long time. As a rule, steel is used for the bowstring (strings or cables) or weaved from silk. True, nowadays there are a huge number of synthetic materials. If you make a bowstring from Kevlar, it is used as a material with high tensile strength (specific resistance).

In powerful crossbows they use a thin steel cable, which serves as a bowstring. You can find this in both cars and motorcycles. Breaking loads are most easily borne by a braided bowstring. This happens due to the fact that a particle of energy goes into friction between synthetic threads. In order to protect the bowstring from abrasion on the stock, use special linings made of plastic or metal.

DIY crossbow drawings

Follow the download link to create a crossbow.

DIY compound crossbow

Sports crossbow shooting in our country is not as developed as bow shooting. This state of affairs is not due to a lack of interest, but to a banal shortage of small arms equipment. Crossbow sport itself undoubtedly has a lot of advantages. It is a vast field for the discovery and application of a certain kind of talent.

Technical characteristics of a homemade compound crossbow:
Overall length -730 mm;
Overall width - 530 mm;
Shoulder length -300 mm;
Height without sight - 180 mm;
Height with sight - 230 mm;
Weight ~3kg;
Cocking force ~30 kg;
Bowstring stroke - 210 mm;

Sight type - optical only (installed software 3.5x17.5, dovetail mounting brackets).
The material of the shoulders was a spring from a 412 “Muscovite”, cut with a grinder, constantly poured water on it to avoid tempering, simply burned the holes with electric arc welding (the edges didn’t seem to come loose);

The trigger force varies from approximately 1 to 1.8 kg, the trigger operates with a warning, and an increase in force is felt before the shot. Shooting performance (shooting was carried out lying down from a rest indoors at a distance of 25 m in three series of 5 shots, fiberglass arrows, weight 25g, length 300 mm. Triple tail height 8 mm):
- maximum radius from the midpoint of impact is 75 mm.
- maximum diameter between extreme hits is 120 mm.
- the average radius of a 100% hit in three series is 68 mm.

The trigger mechanism “rotary nut with sear”, made from spring scraps, was first annealed (t0 = 8500C red heat, held for 10 minutes and slowly cooled with a furnace) and carried out all metalworking, but left an allowance for processing in the places where it will occur friction, then hardened to approximately 45-46 HRC, (t0=8300C light cherry red heat, holding for 10 minutes) and tempering (t0=2950C bright blue tarnish, air cooling). Then I polished all the rubbing surfaces. The mechanism itself is installed directly into the guide on pins. The springs are made from a folding metal meter.

The stock was cut from solid wood (oak), the base was a 30x180 board, the groove in the center was selected using a jigsaw, a drill and a narrow chisel, the treatment was first done with 10% ferric chloride (gives it a black color), and then varnished, but I don’t like this coating I liked it, it was too slippery in wet or sweaty hands.

I had to sand everything and treat it with a special impregnation (I used Danish Oil, which is used specifically for impregnating wood on knife handles), applied the coating several times until it stopped being absorbed, and then sanded the holding areas with fine sandpaper (~500-100 grit for imported paper).

The size of the butt is adjusted to me personally, so if you repeat it, do it with a margin, and then adjust it. The guide is assembled like a package of duralumin/getinax/duralumin/getinax/duralumin, on M3x35 screws, the central plate comes out from the bottom for fastening with the butt, assembled on M6x30 furniture bolts with a semicircular head, on the opposite side it is attached with nuts (the holes for the nuts on the butt are hexagonal, I burned them out secured to a long rod with several nuts).

The material for the guide was a 30x4 duralumin strip; 8 mm of getinax was taken from the instrument panel of the electrical cabinet. The guide drawing is made with a margin, because during manufacturing, the stroke of the string may differ, so it is first necessary to assemble the bow and measure the stroke of the string, and then drill holes for attaching the deck. The deck is argon welded from an aluminum plate 50x5 (bus from a transformer) and duralumin corners 40x20x4, secured to the guide with two M6x40 bolts .

Fastening the shoulders to the deck through spacers (this is necessary because the shoulders have an initial bend, and the deck is straight) and pressure plates with three M6x25 “furniture” bolts (for one shoulder); The earrings for the blocks are made of steel, like the blocks themselves, the weight of one block is ~65 g, if you make the same ones from aluminum alloys, the weight will be reduced to 25 g, I tried to make blocks by casting them in a sand-clay mold, it generally worked, but they were quickly cut by the cable.

The material was technically pure 99% aluminum, and it was not possible to age the material, so I’m content with steel, and I’m thinking about where to get a duralumin blank of a suitable size (or maybe I’ll try using epoxy plastics). The diameter of the blocks is 46 mm, the eccentricity is 11 mm. The bowstring is made of 3 mm steel rope. in a PVC shell, in places of contact with surfaces, additional layers of heat-shrinkable tubing are put on; I use loops to seal the ends and crimp them in the tube, like a clutch on a motorcycle, and the use of studs is necessary both for initial tension and for subsequent tightening during operation.

The string is attached to the blocks through a pin that is inserted into the central hole, and opposite the hole with a dimer of 8 mm, which is opposite the hole through which the axis of rotation of the block passes, under two holes with a diameter of 3 mm are drilled in the groove of the block through which the cable enters the block and wraps around the pin. The string enters the blocks through holes perpendicular to the axis of rotation of the block, and the loops at the ends are placed on the pin, one loop on the upper part, and the other on the lower part of the pin. It was through these holes that my aluminum blocks were cut.

The stirrup is a fabric belt that is draped around the deck, although a steel one can be attached to the deck, and by making it swivel, it can be used as a bipod when shooting prone or from a rest.

When tensioning, I use a device consisting of a pair of blocks and a rope, when I cock it, the rope is thrown over the butt, and I attach a bowstring to the clips of the blocks and pull the ends of the rope, the gain in strength is twofold, which is quite enough for non-tiring shooting, I took the idea from the book by Yu. IN. Shokarev "History of weapons, bows and crossbows."

Video on how to make a crossbow, super powerful

Just twenty years ago, a bow or crossbow for individual use did not exist in nature. Some eccentrics and fanatics of historical reconstructions took on making them at their own peril and risk, having absolutely no idea what they would get in the end. And all because the process of accumulating experience and honing skills in the manufacture and use of throwing weapons, which lasted several tens of thousands of years, in our time was once interrupted and anathematized.

Now all this rare knowledge has been taken out of dusty chests, they have learned to make bows and crossbows using modern technologies, and the army of followers of William Tell and Robin Hood is growing at an exponential rate. And today we have prepared drawings and diagrams for you that will tell you how to make a crossbow at home.

Despite the abundance of online stores selling throwing weapons, as well as a fantastic range of products, there are many who want to make a crossbow on their own. Most of them don't know where to start. Today we will tell you about the main design features of the crossbow. This knowledge will help you avoid manufacturing errors, as well as frustration and injury when using it.

Before starting work, there are two main points to know.

1. In our country, a crossbow is recreational and sporting weapons. Hunting with it is prohibited. Any throwing weapon with a tension force of more than 43 kilograms is considered a combat weapon, the right to use which is given by the licensing authorities of the Ministry of Internal Affairs.
2. Crossbow is a structure that experiences enormous loads during operation. Therefore, any carelessness in its manufacture will most likely lead to injury. Any part of it must have a multiple safety margin.

So, let's learn how to make a simple crossbow at home.

The video below will tell you how to make a crossbow at home:

Onion

The crossbow's energy source is the bow - an elastic plate of complex shape, having one main bend and, as an option, two additional ones at the ends. You need to start making a crossbow with this particular part and adjust everything else to it - choosing the type of tension (recurve or block), the size of the stock, the type of trigger.

Wood and composite

The urgent question is what to use as a material for the bow: wood, composite or metal?

• Tree- the worst choice. Available “pieces of wood” lying underfoot are garbage, suitable only for lighting stoves. Branches cut down in the forest lose their elasticity as they dry, crack and fall apart. From this material you can only make something for short-term entertainment in the country. Of the models sold in stores that contain wood, the one that is very popular is also the one.
• Composite, created from fiberglass and epoxy, is very tempting and simple in appearance. But there is an obstacle - the need to scrupulously adhere to the technology of all work. Mix proportions, drying, aging. At home this is almost impossible.

Metal

There is only one option left - metal. If you have an old Moskvich with a set of leaf springs on hand, consider yourself lucky. One sheet is taken from the entire package - the second. If you are not too scared by the dimensions, then the first one will do. Moreover, it has tubes at the ends - an almost ready-made bracket for attaching blocks or bowstrings.

A block is used to attach the bow to the stock. This is a U-shaped design that wraps around the stock from the front. It can be welded tightly to the spring leaf, but in this case, when the bow is bent, the welds will experience excessive pull-out stress. Therefore, it is better to attach the ball joint from the VAZ 2108 to the block. The bow is attached to its pin. This is also convenient because there is a hole on the spring leaf.

If you are very strong, then you can choose the recursive method of tensioning the bowstring (as in, etc.). But it’s better to choose a block one (as in models, etc.). To attach the blocks to the bow, if you have chosen a second spring leaf, you need to attach brackets to its ends. A bolted (or even better, rivet) connection is preferable to welding, since this unit experiences strong vibration loads. As pulleys, use parts of the window lifting mechanism of the same Moskvich.

Regarding the bowstring, an obvious solution arises: a thin metal cable. But it is not entirely correct, since steel cables do not withstand variable loads well. It is better to choose a climbing cord with a diameter of 5-8 mm.

Once you've made your bow and attached the string to it, you can conduct full-scale bending tests. It’s great if you have a dynamometer of 100-150 kilograms. As a result, you will learn two parameters necessary for further work: the length of the bowstring stroke and the load.

Read below to learn how to make a stock for a powerful crossbow at home.

Lodge

For this part of a homemade crossbow, wood is the only option. But not everything. In any case, not aspen, alder, spruce or pine. Better beech, elm, oak. The product has been dried for twenty years. It is clear that you will never find something like this anywhere. Therefore, use moisture-resistant plywood with a thickness of 7-9 mm. 3 or 5 contours of the stock are cut out of it, and then this package is glued together with epoxy resin. Not very pretty, but extremely reliable.

• Regarding the shape, give up the semi-pistol style and use a straight English stock. It is not only easier to manufacture, but also stronger.
• When assembling the stock package, it is necessary to take into account both the course of the bowstring and the load. The first determines the distance from the block to the slot for the trigger mechanism. The second is the thickness of the stock walls at the place of its attachment. It is the straight English stock that will allow you to avoid excessive thinning when moving from the forearm to the butt.
• The most important part of a crossbow stock is the arrow guide. It should be smooth and durable. For it, you can use the plates framing the side windows of the Moskvich, furniture fittings, and other similar-shaped parts.
• If you use a block type of bowstring tension, then there should be a groove in the forend under the guide for the cable system. This is another element that weakens the stock, so give up the idea of ​​making the forend dainty. High will protect your fingers from getting caught under the bowstring and traumatic amputation of the phalanges.

Typically crossbows have a plastic stock, such as models and others.

Below we will tell you how to make a homemade trigger mechanism for a crossbow at home.

This video will tell you how to make a crossbow from wood (plywood) with your own hands:

Trigger

If you are not a sixth-class mechanic, then give up the idea of ​​making this element yourself. Make an effort and find the trigger for any spring-piston air rifle. In the most difficult case, you will only have to modify its tooth that holds the piston - it may be too small for a thick bowstring.

A casing with a height of 2 to 5 cm is placed above the trigger mechanism, which is necessary to protect it from moisture and dirt, and also serves as the basis for sighting devices - rails for optics or rear sights. Weaver, Picatinny or dovetail rails can be purchased at any online store that sells pneumatics.

The front part of the casing above the trigger mechanism is made in the form of a long (no more than 10 cm) elastic “tail”, which holds the back of the arrow on the guide.

Making arrows

Canonically correct crossbow ammunition is called a “bolt”. But many online stores sell crossbow arrows. For crossbows with a rifle stock, lengths of 14, 16, 20, 22 inches are suitable. To be completely honest, you won't find better magazine arrows. Unfortunately, none of them are worth less than 150 rubles. Therefore, it is worth trying to make them yourself.

They can be made from straight-layer wood without knots. As an option, use furniture parts - balusters from chairs, railings of cribs. Good arrows are made from aluminum tubes up to 2 cm in diameter. If desired, you can even use electrodes of the maximum diameter, but they bend hopelessly when hit and it is difficult to attach the feathers to them.

Thin plastic is used for the plumage. Natural bird feathers can give the unexpected effect of chaotic changes in flight direction, since they have natural curves that must be taken into account.

The main condition for a good, smooth flight is balancing. The center of gravity of a crossbow bolt should be after the first third of its length from the tip. If it is not metal, the end of the arrow can be loaded with lead wire wrapped around the shaft.

The issue of equipping an arrow with a tip must be treated without fanaticism. Sharpening metal on lathes, milling and polishing, giving it exquisite shapes - these operations are accessible to few. In addition, such a tip is extremely dangerous. If you do not need to pierce knight's armor, then a wooden bolt can simply be sharpened at an angle of 30 degrees using a regular knife.

We will tell you further how to make a crossbow that shoots with your own hands from paper, pencils and other materials.

Cool shooting games

Shooting with toothpicks or matches can be made from a wooden clothespin. To do this, disassemble it and remake it:

1. widen the narrow groove for the spring of one half to 1 cm, make the same on the second, but with an indentation of 1 cm;
2. at the front ends of both halves, on the side of the narrow grooves for the spring, make a longitudinal groove 1-2 mm deep;
3. assemble the halves of the clothespin “inside out” by twisting them with thread;
4. install the clothespin spring with its paws in the cut grooves, and with the spiral outward;
5. place a toothpick in the hole between the halves;
6. press the spring spiral, moving it into the semicircular cutout;

The spring tab will slide along the long slot, clicking on the toothpick and causing it to fly out.

To learn how to make a mini crossbow from pencils with your own hands at home, watch the video below.

Do you want to make a real crossbow that will not only look like it, but will also shoot? Then don’t pass by and read our article on the topic of how to make a crossbow with your own hands. In the article we will not only talk about the intricacies of this matter, but also show the whole process in the photo. The topic is especially relevant in the summer, when you can go out into nature and shoot at targets. And a thing made with your own hands will delight not only the eye, but also your friends or acquaintances, who, having seen such a product, will certainly set a goal and desire to own it!

How to make a crossbow with your own hands

Among simple tools created with one's own hands, the bow definitely wins. However, crossbows are also very popular. If you want to make a crossbow with your own hands, you just need to read the instructions below. A medieval design was chosen as an example due to its simplicity. Such a crossbow does not require metal welding; it can be made at home; it also does not require the presence of springs, as in its other, more advanced variations.

All that is needed to make a simple medieval crossbow is the desire to craft. Initially, you need to find a suitable stick for the base of the structure. It is recommended to use bird cherry, since after drying the wood retains good elasticity characteristics. When a suitable branch is found, you should carefully saw it off, completely remove the bark and leave it to dry in a warm place.
Typically the drying time is about 5-7 months.

Step-by-step instruction:

In addition, it is recommended to immediately bend the stick so that it does not crack during processing and fixation, as well as during use. If bird cherry is not available in the area, you can use elm or other alternative wood.

It should be remembered that for good strength, durability and elasticity of the launching part of a home crossbow, you need to stand it well. Moreover, in this case, the chances of a crack during operation of the crossbow will be significantly reduced.

To have the opportunity to practice and to avoid the need to wait again, it is recommended to prepare several sticks at once.

You can use any type of board or dry wood on the stock of a homemade crossbow. It all depends on how accurately you want to replicate the medieval model of the weapon.

Once the wood has been selected and processed, a notch needs to be made in the front of the wood to accommodate the crossbow bow. You can make a notch with any tool from a metal file to a regular knife.

The next step in making a crossbow with your own hands at home is to drill holes for the bow bolts. They are placed at a distance of 8-10 cm from the front of the bed. Previously, holes were made with red-hot metal, so you can also use this method if you don’t have the right tools at hand.

Moreover, if you don’t have any bolts at hand, you can use the same wood.

The upper plane of the stock should have a groove in which the crossbow bolt will be placed. Often this groove is made round, but it is recommended to plan it triangular to increase the accuracy of the bolt.

When everything is ready, you can fix the bow. This is applied to the cutout made in the front of the stock and tied tightly with rope to the previously installed bolts or their wooden alternatives. This will be enough, but for a tighter fixation it is better to use glue.

The last element of a homemade crossbow is the organization of the trigger mechanism. Usually the simplest lever type is used. The crossbow drawing below shows how such a system works.

When the bracket-lever is lowered, the pin instantly launches, and it launches the bolt forward. It is important that this system does not have any safety mechanisms, so the bolt must be installed only before firing.

The created crossbow must have a tension force of about 40 kg, so the design will not be included in the list of edged weapons. The bowstring is tensioned by hand, so additional mechanisms are also not required.

Drawings for making at home

The photo above schematically shows a crossbow with all the necessary dimensions. Its main value is to understand what size its parts should be in relation to each other. Its entire length is 732 mm, with a height at the sight mounting point of 223 mm. The drawing shows a “pistol” handle (shaped like a pistol), for a reliable and comfortable grip.

The second hole is made to facilitate the construction, since the total thickness of the plywood handle (can be made of wood) is 30 mm. The arms are 302 mm long and are a universal option; their total length is 532 mm. For the first time, it is enough to make exactly according to the dimensions indicated in the diagram, and after testing, make adjustments.