Wood crusher: selection tips and review of popular models

Wood chips are a highly sought after material that is suitable for a variety of applications.

It is obtained mainly as waste from wood processing.

The types of wood chips for different applications, which are determined by the shape, size and type of wood, can vary greatly.

In this article we will talk about the various equipment that is used to produce wood chips.

We will also talk about the influence of the type and configuration of equipment on the characteristics of chips.

What is she like?

A wood chipper is a unit designed for chopping wood . It has found application in logging and woodworking, in homestead farming and in breeding farm animals. In the first two cases, the device is usually used for disposal or recycling of waste and garbage. In the second - for the preparation of feed (goats and rabbits like to eat chopped branches of some tree species).

Types

Wood crushers are divided into several types according to certain criteria.

Depending on the scope of use, they can be professional or household. Professional ones are much larger and more powerful, sometimes combined on the same platform with a truck. Units for summer cottages and household plots are quite small, they are convenient to store in utility rooms (or even on the balcony) and transport in a car. Also, as an independent type, we can distinguish a feed crusher designed for grinding feed. It is very similar to the household one, but differs from it in the size of the dispersion obtained at the output - it is partially optimal for consumption by pets.

According to the mechanism of crushing material, crushers are divided into the following types:

• Knife . The branches are crushed in it due to rapidly rotating disc blades. Most often, such a mechanism is used in household equipment, since it is not capable of chopping branches thicker than 40 - 45 mm.
• Auger . The wood is crushed in such a unit using a special shaft called an auger. Passing between the shaft and the guide, the branches are literally crushed, turning into a mushy mass.
• Hammer . A wood hammer crusher crushes wood by striking a metal block (or several blocks). The mechanism is quite voluminous and is capable of crushing even whole tree trunks. This led to its use in the logging industry.
• Cheek . Consist of a movable and fixed cheek. The movable presses the material being processed against the stationary one and exerts strong pressure on it. As a result, the wood is flattened and crushed. Mainly used in the professional field.
• Conical . The basis of the mechanism is a glass and a movable cone-shaped finger. The wood is placed in a glass, the finger moves and crushes it.

Depending on their ability to be transported, units are divided into mobile and stationary. The former are either a compact device or a unit on wheels that can be transported from place to place using a car. They can also be made on the same platform as a truck, in the form of a self-propelled vehicle. The latter are installed in one place for a long time.

Expert opinion

Levin Dmitry Konstantinovich

For a summer residence, it is best to choose a small mobile crusher. This will allow you to easily transport it to your apartment for storage at the end of the warm season using your personal car.

According to the type of power supply, wood crushers can be:

1-Fuel powered crusher 2-Electric crusher

• Gasoline or diesel.

• Electric.

Manual crushers are designed for domestic use and are driven by the muscular power of the person who works with them. Gasoline and diesel engines can be both professional and household. They are powered by an internal combustion engine. Electric ones operate using an electric motor, powered from a household electrical network with a voltage of 220/230 V. This type of crushers has found application both in the professional sphere and in everyday life.

Please note that gasoline and diesel crushers are very noisy, so working with them is not very comfortable. But electric ones produce much less noise during operation, although it is also quite noticeable.

How to make a wood chipper with your own hands

general information

A wood chipping machine (garden crusher) allows you to forever forget about the need to light a fire in order to dispose of wood waste. Wood chippers are capable of processing raw wood material into sawdust, which can always be used for soil cultivation or for the manufacture of building materials.

A practical owner will never allow the most valuable fertilizer - sawdust - to burn without a trace. A properly organized compost heap will turn this goodness into an environmentally friendly and rich fertilizer in a short time.

NemodnyFORUMHOUSE user

I began to use slightly stale sawdust and decompose it with the help of nitrogen-fixing bacteria (there is 78% nitrogen in the air). Loosening is a must. I plant it right in the sawdust.

About the production of building materials based on wood chips: if you have heard of such a concept as “arbolit”, then you will understand what we are talking about.

And, by the way, some heating boilers successfully operate on fuel made from sawdust. Consequently, the scope of application of material obtained from wood that has served its age is large. Therefore, making a machine for chopping wood is a justified undertaking.

Garden crusher diagram

Studying the design of any mechanism begins with studying the diagram and principle of its operation. Let's start with the diagram.

This image shows a visual diagram of a garden shredder. Let's list its main elements:

• Frame – consists of posts (1) and a base (2).
• Drive mechanism – belt tensioning mechanism (15), motor (8), belt (13) and drive pulley (14).
• Shaft with fan and cutting elements (items 4,5,6).
• Receiving device – feeding hopper (9), pre-presser (10).
• Protective cover (items 11 and 12).
• Calibration grid (item 7).

If all machine components are assembled correctly, if the welding seams are reliable and the cutting elements are strong, then the machine will be durable and easy to use. It will ensure good grip of the processed wood, and at the output you will receive sawdust of the required size.

The operating principle of the mechanism is as follows:

1. The engine (electric, gasoline, etc.) transmits torque (using a chain or belt drive) to a shaft with cutting elements.
2. The stem (or block) entering the receiving chamber is captured by the chopper knives and cut into small chips.
3. The chips enter the chamber of the hammer crusher, where they are crushed to a given fraction.
4. The crushed wood chips spill through the crusher grate and, under the action of the fan blades, are thrown out of the device through the outlet.

Frame

Considering that a wood crusher is a bulky mechanism (and also prone to vibration), its frame should be made of a durable metal pipe (with a wall thickness of 4 mm) or a rigid metal angle.

It would be a good idea to equip a mobile version of a wood chipper with a couple of wheels.

The dimensions and other features of the frame depend entirely on the dimensions of the equipment mounted on it and on the performance of the machine.

Drive unit

The design of the drive is essentially simple: the tension mechanism, pulleys and belts - all this can be made or purchased without any problems. The key challenge we have to solve when developing the drive design is the selection of a suitable motor.

The engine can be used either electric or gasoline. Gasoline-powered machines have a more complex design. Machines with an electric motor, on the contrary, are more compact and easier to operate. For stationary do-it-yourself wood chippers, it is preferable to use an electric motor. For mobile machines, a gasoline engine is more suitable. Among the successful models that FORUMHOUSE users were able to assemble on their own, electrically driven machines predominate. Therefore, we will consider them in this article.

The engine should be selected based on its power. The engine power must be at least 4 kW. This indicator is enough to chop garden branches with a diameter of up to 4 cm. The optimal speed on the shaft of a home-made shredder should correspond to 1500 rpm.

A significant reduction in speed (1000 rpm or less) on the working shaft of the crusher leads to a decrease in the force of the air flow, which pushes the crushed mass out of the crusher. And this can lead to quite predictable consequences: clogging of the drum with sawdust, loss of power, etc.

Ana789FORUMHOUSE user

In the discussion of shredders there is information that the number of rotor revolutions should be within 1500 rpm.

If, in addition to chopping garden branches, you pursue other goals (preparing raw materials for the production of wood concrete slabs), then your DIY wood chipper will certainly require a power reserve. The number of revolutions on the working shaft of the crusher can also be changed (both up and down).

Volodaris FORUMHOUSE user

The 5.5 kW engine turned out to be weak. With such a feed, he could not handle the 50x50 beam. Apparently, this is due to good self-grabbing of wood. Therefore, modifications to the machine began (in order not to buy a powerful motor, which would require at least 11 kW).

The optimal number of revolutions on the crusher shaft can be obtained by changing the diameters of the drive pulleys.

Volodaris

The engines on the first machines were three-thousandths - only because there were no 1500 rpm.

Disc chopper shaft with cutting elements

Perhaps the most complex part of our machine is the crusher - the crusher shaft (on bearings), with a crushing cutter and hammers (bits). Let's begin our consideration with a chopping cutter, consisting of a flywheel (disk) with knives.

The key parameter of the disk, which directly affects the performance of the crusher, is its diameter (from 350 to 600 mm). There is no point in doing less.

Volodaris

In my opinion, this is a dead-end solution (I mean a 200 mm disc). Knives can be placed there, with a shaft in the center, say, 50 mm. There will be nothing left of the disk. In my case, my machine did not allow me to make the disk larger (350 mm with a thickness of 15 mm - this was the edge). Everything that was done was done without leaving home. But there is nothing wrong with ordering a disc from any turner.

In this case, a metal sleeve was welded to the disk during the manufacturing process. After the disk was mounted on the shaft, the sleeve was welded to the shaft itself. Thus, the cutter was securely fixed to the shaft.

As you can see, 350 mm is the minimum. The user "Kirasir" went further, making a disk with a diameter of 600 mm and a thickness of 33 mm, taking the dimensions of parts from a Chinese crusher as a basis. There were 3 knives installed on the disk. The chopper is driven by an 18.5 kW motor.

The knives mounted on the cutter disk deserve special attention. Steel for knives must be strong, so FORUMHOUSE users recommend using car springs as the starting material for knives.

Volodaris

The knives are an ordinary spring (I think from a GAZ-52). I did not do any preliminary tempering (as well as hardening). The knives themselves were collected in a bag and processed to the desired size using sandpaper.

Drilling a spring is a labor-intensive task. And in order to achieve a positive result, the workpiece should be drilled on a machine (lathe or drilling) that allows you to set the spindle speed at low enough speed (so that the drill does not burn out).

The length of the knife must correspond to the length of the working slot on the disk.

The performance of the crusher and its ability to independently capture the supplied wood will depend on how correctly the knives are sharpened. With a good grip, the wood falls into the machine without outside help.

The knife sharpening angle (self-sharpening angle) should be 30°.

When sharpening the cutting element, it is necessary to create a backing (bevel on the back surface of the knife - at an angle of 2°...3°). Backing is needed to ensure good self-grabbing of the supplied wood.

VdoVinFORUMHOUSE user

According to science, the reverse angle should be about 3-5 degrees.

Hammers (bits) for subsequent grinding of wood chips must be made removable. At this stage there should be no difficulties. After all, the design of the removable mechanism is quite simple, and if it is based on bolted connections, then failed parts can be quickly replaced if necessary.

This is what a user of our portal says about the design of the hammers.

Volodaris FORUMHOUSE user

I made the hammers themselves from simple sheet steel 4 mm thick. If you only chop wood, then their strength will be sufficient. As for sharpening: I don’t see the point in it - everything works just fine.

Regarding the width of the hammer mechanism: the author of the presented design believes that a design of 4 hammers should not occupy more than 90 mm.

The disks of the reel shown in the photo are made of 6 mm thick steel sheet. The fan blades can be made from the same material that the bats were made from.

Balancing the drive shaft is not an easy task, but if possible, it should be done. This will relieve the machine from unnecessary vibrations and significantly extend its service life.

Kyper777FORUMHOUSE user

I first balanced the disk itself on the centers (I first assembled everything except the hammers). This was the first rough balancing act. Then I balanced it on the knives (I think there shouldn’t be any imbalance). When I assemble the hammers, I will also adjust them according to weight.

The wood crusher shaft is best mounted on double-row self-aligning bearings. When working in conditions of vibration and uneven loads, the advantages of these products are undeniable.

If the crusher is made for the banal grinding of branches, and the size of the chips coming out of it is not important to you, then it is not necessary to include a hammer mechanism (as well as a calibration grid) in the design of the machine.

Protective cover and receiving device

The design of the casing is best considered in conjunction with the receiving device. The dimensions of the casing depend on the productivity of the machine, or more precisely, on the size of its working parts (mill, hammers, etc.). The thickness of the casing walls must be sufficient to withstand intense loads, if possible acting as a shear resistance element. It is advisable to make the casing with a hinged lid (for ease of maintenance of the machine), as shown in the figure.

The design of the presented casing is fully working. The only thing that was modified during the process of setting up the machine was the window for the loading hopper (the inclination of the loading device changed, and, consequently, the configuration of the inlet opening was changed).

The user Volodaris made two machines with housings of different thicknesses: 6 mm and 12 mm. In the design of the second machine, the role of a counter-cutting element is played by a casing wall with a thickness of 12 mm. The machine is fully operational, but to increase reliability, the casing should be equipped with a counter knife (ideally removable). This can be implemented as follows: weld a rigid plate to the casing, to which the removable counter-knife will be attached using bolts.

The anti-cutting element must be no less durable than the cutting knife. Therefore, it is better to make these parts from the same material. As for the sharpening angle of the counter knife, it should be straight.

Sandugach FORUMHOUSE user

I believe that durable metal is needed, because the load is considerable, and a clear angle is needed - 90 degrees. If I'm wrong, I'll be glad to read other versions. 90 degrees is the sharpening angle of the counter knife.

The smaller the gap between the cutting and counter-blades, the shorter the chips will be. Consequently, the specified distance can be minimized (the main thing is that the knives do not cling to each other).

In principle, the gap between the cutting and counter-cutting element of a crushing machine can be adjusted during operation. This will allow you to obtain the optimal degree of wood chopping. For example, a user of our portal, registered under the nickname Phoenix83, makes adjustments by moving the cutter along the axis of rotation. But you can do it easier by placing washers of various thicknesses under the counter knife.

The loading hopper can be made of the same material as the casing itself. Considering the relatively low load on this unit, its walls can be made a little thinner. The design of the loading hopper is extremely simple, and if the crusher knives are sharpened correctly, then the need to include a pre-presser in the design of the feeding device disappears by itself (self-grabbing of wood in this case will be at the highest level).

When mounting a loading device, the most difficult thing is to choose the correct angle for its installation.

Volodaris

Many people play with this angle: the steeper it is, the better the self-capture. I make it approximately 120-130 degrees. The operation of the machine suits me quite well.

Sieve

A metal sieve (sieve), installed along the inner circumference of the casing, helps to sift out sawdust of the required fraction. The size of the holes in the sieve depends on what kind of chip fraction you want to obtain. It is often determined experimentally. Thus, the user Volodaris made holes with a diameter of 20 mm, being prepared in advance, if necessary, to change the specified size.

Patriot 777FORUMHOUSE user

I used a sieve with oblong holes - 10*50 mm.

When installing a sieve, you should definitely pay attention to the size of the working gaps: between the sieve and the casing, as well as between the hammers and the sieve.

The clearance between the sieve and the casing should ensure unhindered movement of the crushed mass, preventing the crusher from clogging with sawdust. According to FORUMHOUSE users, a gap of 10 cm is enough for smooth operation of the device.

As for the gap between the bits and the sieve, it should be minimal. It is desirable that the length of the hammers extends a couple of centimeters beyond the diameter of the chopping cutter.

We bring to your attention a simple and reliable way to attach the sieve to the machine casing.

Volodaris FORUMHOUSE user

Bolts are welded along the diameter of the casing, onto which the sieve rests. The upper part of the casing presses the sieve with exactly the same bolts. A limiter is welded to the sieve, which, resting against the bolts, does not allow the sieve to rotate.

We looked at the most common design of homemade machines for chopping wood. You can learn more about the features of homemade garden crushers, as well as their working dimensions and technical parameters, on the pages of our forum. You can discuss the questions presented in the continuation of the existing topic. A video about building a house from wood concrete blocks will help you find the answer to the question - in what areas of activity can wood chips be used?

What to look for when choosing?

Here are some important points to consider when choosing a wood chipper:

• Purpose of use . When purchasing equipment for a summer cottage or personal plot, there is no need to purchase professional crushers. They are very expensive, and their power is excessive. A regular household wood chipper will suffice.
• Engine's type . Please note that gasoline and diesel crushers are much more autonomous than electric ones. You can work with them anywhere, including away from home. But electrical equipment requires a connection to a household power supply. However, if you do not plan to use the unit outside your garden plot, you can limit yourself to an electric one.
• Principle of operation . It is believed that a screw crusher is most suitable for a summer residence. It is capable of processing thicker branches and functions more stably, unlike a knife one.
• Build quality . All parts and components of the unit must be tightly fitted to each other, their fastening must be reliable. This is very important because the crusher has parts that rotate at high speed and can cause injury if broken.
• Manufacturer . Today, crushers from a variety of manufacturers are available on the market. There are both expensive devices from world-famous brands and cheap Chinese devices. Obviously, the former are more expensive than the latter, but they are distinguished by higher quality, reliability, and maintainability.

The price range among crushers is very high. But we do not recommend saving on equipment. Everyone knows the proverb that says: “the miser pays twice.” A cheap Chinese device most likely will not last long and will not be stable. However, this does not mean that you have to overpay. If you do not have the opportunity to buy an expensive unit, it is better to purchase equipment in the mid-price category. It will not require overpayment for the brand, but at the same time it will be of high quality and reliable.

Best models

Below is a short ranking of the six best wood chippers. It contains both professional equipment intended for use in logging and feed processing, as well as devices for a summer cottage or garden plot.

Atlas Copco PC1055J

This is a professional level crusher for logging work. It is a self-propelled tracked vehicle weighing one and a half tons, equipped with a SAT diesel engine with a capacity of 250 horsepower.

The crushing mechanism is jaw crushing with hydraulic adjustment of the compression force of the processed material. The entrance hole is rectangles, one side of which is 100 centimeters, and the other is 50 centimeters. This allows the unit to be used for chopping the trunks of young trees, shrubs, and pre-prepared large trunks.

Atlas Copco PC1055J weighs 33 tons, the length of the machine is 5.5 meters, the width is 2 meters. A new crusher costs about 8,000,000 rubles. However, used cars can be purchased at a price within 1,000,000 rubles.

DM-T

DM-T is an inexpensive stationary wood crusher of domestic production. Moving is not provided: the unit is fixed to the floor using screws or bolts.

This model is best suited for domestic use or for small wood processing enterprises (for example, a sawmill, a carpentry workshop).

The DM-T weighs half a ton, the length of the unit is 1.4 meters, the width is 0.7 meters. The operating mechanism is hammer.

It can be bought for 50,000 – 60,000 rubles. The device runs on electricity.

SKORPION 120 R

SKORPION 120 R is a universal mobile crusher. It can be transported as a trailer on a truck or as an attachment on a tractor (for this, the wheels are replaced with a special rack).

The SKORPION 120 R is powered by a Lambardini petrol engine with 28.5 horsepower. The grinding system is knife. In total, the design includes four knives: two main and two additional (they chop what the main ones couldn’t handle).

You can chop shrubs, medium-sized tree trunks, and pre-prepared wood material.

The average cost of SKORPION 120 R is 1,300,000 rubles.

RM-520

Domestic stationary wood crusher. Unlike the DM-T described above, the RM-520 is equipped with a gasoline engine from the Chinese company Lifan, as well as a special socket for discharging chopped wood.

The grinding system is auger. At the same time, the PM-250 auger shafts are equipped with special teeth, which make it possible to grind the processed material to a state close to sawdust.

Despite the fact that the RM-250 is a stationary device, it can be easily transported in the back of a truck. This makes the device very convenient for clearing bushes from power lines, railway embankments, and roadsides.

The crusher is one and a half meters long and 0.7 meters wide. The mass of the unit is 350 kilograms.

The cost of PM-250 on the Russian market varies greatly. A new device costs about 700,000 rubles. However, on the secondary market this model can be purchased for less than 100,000 rubles.

STIGA BIO SILENT 2500

STIGA BIO SILENT 2500 is a household wood chipper. Due to its size, it is perfect for a summer house or homestead. It cannot be used for professional purposes. This is due to the fact that the device can only process branches with a diameter of up to 40 mm.

STIGA BIO SILENT 2500 operates from a household power supply voltage of 220/230 V. The power of the device’s electric motor is 2,500 Watts. Weight – 27.5 kilograms. This makes it easier to transport the device. The set includes a special container for recycled wood with a capacity of 60 liters. The branch processing system is auger.

The average cost of STIGA BIO SILENT 2500 is 15,000 rubles.

CALIBER ESI-2400N

CALIBER ESI-2400N is an ultra-compact garden wood chipper of domestic production. It operates from an electrical network with a voltage of 220/230 V. The grinding system is knife-type. Thanks to its light weight and small dimensions, CALIBR ESI-2400N can be easily transported in a car and stored on the balcony of a city apartment.

Engine power CALIBER ESI-2400N – 2,400 Watts. The maximum diameter of processed branches is 40 mm. There is no waste container. For transportation within the personal plot, the device has two wheels. There is also a metal stop that is used during operation.

A distinctive feature of CALIBR ESI-2400N is its low price. It ranges from 7,000 to 8,000 rubles.

Equipment for the production of

Equipment that is suitable for producing wood chips includes :

• drum chipper;
• rotary chopper;
• hammer crusher;
• shredder

Drum chipper

This is a multifunctional unit that is used both for producing wood chips and for producing various types of shavings.
The basis of this machine is a drum with a diameter of 30–150 cm, on which 4–8 cutting and 4–20 separating knives are installed .

In addition, the machine is equipped with a drive that feeds the wood to the drum and prevents it from flying out.

If, after separation from the total mass of wood, the chips are too large in size, then the knives drag them along the sieve until they either split or are cut by additional knives mounted on the body.

The size of the finished product depends on:

• drum diameter;
• number of knives;
• wood feed speed;
• drum rotation speed;
• angle of entry of knives into wood.

The larger the diameter of the drum, the more time passes between cuts at the same rotation speed, which means the thicker the cut material will be.

In the same way, the thickness of the material is also affected by the number of knives , so if it is necessary to obtain thick chips, half of the knives are removed (every other one, so as not to upset the balance).

feed speed and drum rotation speed on cheap machines are not adjustable , but on homemade or expensive devices this is possible, thanks to which you can change the size of the chopped wood within a wide range.

The angle of entry of the knives into the wood determines the size and shape of the finished product. When it is 90 degrees, that is, the wood fits right in the center of the drum, then the cut occurs strictly along the grain.

Moreover, first, separating knives act on the wood, cutting deep vertical stripes in it, then cutting, separating a thin layer , which immediately falls apart into strips , the width of which is equal to the distance between the separating knives.

Due to their small thickness, these strips break into narrow fragments corresponding to annual rings, because the strength of the connection of the wheels to each other is much lower than the strength of the wood inside one ring.

As the angle of entry of the knives into the wood decreases, the shape of the final product also changes.

After all, the smaller the entry angle, the greater the length of the annual layer caught in the cut fragment, which means the greater the width of the piece separated from the cut plate.

In this case, the thickness of each piece turns out to be noticeably less than its width , due to which the shape of the finished material fully satisfies the requirements for wood chips for the production of wood concrete.

Therefore, by changing these parameters, it is possible to obtain both wide chips suitable for the production of OSB and chips similar to rectangular chips for smoking or infusing alcohol.

The drum chipper can process any long wood whose diameter does not exceed the throughput capacity of the unit.

Therefore, most often the machine is used for chopping round wood, that is, debarked or unbarked trunks and thick branches.

In addition, the machine is also suitable for shredding long scraps , however, there is a limitation on the minimum thickness due to the peculiarities of the feed mechanism.

This unit is not suitable for processing used boards and logs , because an undetected nail will damage the knives and sharply reduce the efficiency of the mechanism.

Rotary chopper

The basis of this device is a heavy and thick rotor , which acts as a flywheel and is a platform for installing knives (usually 3 pieces).

The wood is fed through a special chute at an angle of 50–80 degrees, which increases the width of the cut annual rings, and hence the size of the crushed product. A counter knife is installed between the rotor and the housing on the wood entry side , facilitating the operation of the device.

After all, a chopping knife moving from above and a counter-knife fixedly mounted on the body create an analogue of scissors and not only increase cutting efficiency, but also eliminate wood from being pulled under the rotor and jamming of the unit.

Typically, such a grinder is used in tandem with a hammer crusher, installing them in a common housing. This combination completely eliminates the plates with several undivided growth rings, resulting in a needle-shaped finished product.

If there are no strict requirements for the shape and width of the chips, then a rotary chopper is used without a hammer crusher.

The main purpose of this device is processing cut branches , which is why such devices are often called garden shredders.

The unit is also suitable for processing thin trunks and various scraps of any length, the only limitation is related to the cross-section of the wood. After all, the gutter rests on a window with a relatively small cross-section (from 10x10 cm for garden ones and up to 30x30 cm for industrial ones).

Hammer chip crusher

This apparatus consists of a shaft with support disks, between which there are fingers that hold hammers, that is, rectangular steel plates that rotate freely around their axis.
Also, fender plates are welded to the shaft.

When the rotor disk has completely spun and its rotation speed has become constant, the hammers , due to the action of centrifugal force, form a three-rayed star .

Any change in the rotation speed also leads to a change in the position of the hammers, so they hit the impact plates designed for this purpose either in front of them or behind them. Moreover, the impact force is sufficient to separate the wood along the boundary of the annual rings, but not sufficient to damage the fibers.

Typically, such a crusher is used in conjunction with a rotary shredder , because the impact energy of the fingers is not enough to separate large fragments of wood.

Therefore, most often a complex consisting of a shredder and a crusher is used for the production of wood chips.

Indeed, despite the extremely low cost compared to a drum machine or shredder, such a complex produces chips that, in their size and shape, are ideal for the production of wood concrete.

Shredder

Devices of this type consist of a shaft with special hooks or teeth that pass through grooves intended for them. When wood of any shape enters the work area of ​​the shredder, the hooks crush and break it into pieces the width of which is equal to the width of the hooks.

Twin-shaft units are more efficient , because each shaft is both moving in one row and grooves in another row.
Thanks to the enormous torque with which the shaft rotates, the shredder easily crushes wood of any species .

Even a nail caught under the hooks does not affect their condition, because the shredder’s teeth do not cut or plane, but crush the wood, so small defects on their surface do not affect the result in any way.

More expensive and modern models of shredders are equipped with various systems that correctly position the wood, because the size and shape of the chips directly depend on the position of the wood relative to the shafts .

When the wood fibers are located along the shafts, crushing occurs at the joints of the rings, and the chips are of maximum quality. If the material enters the chipper as it turns out, then the chips turn out to be of different types.

Can I do it myself?

You can make the simplest household crusher yourself!
For this you will need:

• Electric motor.
• Transmission belt.
• Table base.
• Two transfer wheels.

• Casing.
• Disc knives or auger.
• Steel shaft.
• Bearings.
• Steel staples.

The transmission wheels and knives (auger) are attached to the shaft, and the shaft itself is attached to the table using steel brackets. Bearings must be included in the design to avoid friction of the shaft on the brackets. The table can be welded from metal or made from wood. A second wheel is attached to the electric motor, secured to the bottom of the table, and the motor wheel is connected to the shaft wheel. A casing is secured around the knives.

Expert opinion

Levin Dmitry Konstantinovich

The casing can be made of galvanized iron, connecting it with rivets, but such a design will not be very reliable. The best solution is to weld it from sheet steel. This is also more preferable because in this case the casing can be given almost any shape. The casing must have a high socket for feeding wood and a hole for waste.

What kind of wood chipper do you use?

GasolineElectric