Do-it-yourself assembly of a tire and disk mini-sawmill. How is a homemade tire sawmill made? DIY tire sawmill at home

For the production of lumber, machines are used for dissolving tree trunks. Tire sawmill with an electric motor represents one of the possible options for individual production of timber or boards.

The primary processing of timber is often sought to be shifted as much as possible to the zone of its growth. Then wood waste will serve organic fertilizer for future forest plantings. Rotting on the ground and in the soil, sawdust, branches, bark, and cutting residues will serve as the basis for the intensive growth of young trees. Therefore, a small-sized structure can be used immediately after felling a tree. It can be easily placed in the trunk of a car. Only lumber will be removed from the forest.

In some countries, the industry produces a trailed band sawmill that can be attached to for a passenger car and take it out to work in the forest.

Sawmills for home use

To make timber and boards with your own hands, several types of devices are used:

• Frame, installed on a strong foundation. At least three people are involved in servicing. Are different high level power consumption and performance. General view of the frame type sawmill:

• Band saws can cut logs large diameter. Individual samples equipment are capable of dissolving a tree trunk with a diameter of 3 m. General view of the band sawmill:

• Disc saws are quite often used in private households for sawing wood. Some samples are capable of processing wood with a diameter of up to 1 m. General view disk sawmill(it can be seen that it uses discs installed perpendicular to each other. Cutting is performed in different planes in one pass):

• Tires as a working tool are tires for electric and chainsaws. By using similar devices Single users can turn logs with a diameter of about 60 cm into lumber. The simplest bus sawmill (in this design the saw moves along a guide made from a channel):

At logging enterprises, frame installations are most common. Setting up for the production of a certain format of lumber is quite simple; the required distances are set between the saw blades. It is quite difficult to use such sawmills on a personal basis. The installed power of the drives reaches 30...40 kW.

Tape equipment has been in use relatively recently (about 30 years). Typically, the saw blade thickness ranges from 0.8...1.0 to 2.5...3.0 mm. In practice, automatic machines are used that perform cutting according to a given program. To work, just enter the necessary data and install the workpiece. The auxiliary workers will clear the table ready-made boards and timber.

Some do-it-yourselfers make such machines on their own. They are attracted by the opportunity to create a relatively simple device. They can be used when going into the forest, organizing a wood processing workshop for logging.

Disc sawmills are structurally the simplest. A large diameter disc is used, which performs a long saw according to the specified parameters. In practice, double-disc machines are used that cut logs from both sides. This approach allows the use of relatively small disks.

Using a saw bar with an electric or gasoline engine allows you to use them to perform long rip sawing. Some craftsmen make mobile sawmills that can be transported to a construction site or to the forest. You just need to organize the layout of the logs on supports and install auxiliary devices that ensure the linear movement of the working body.

In practice, tires are used with and without fixation in the frame. If you fix the canvas on a rigid frame, it is easier to obtain a processed flat surface. The frame prevents movement to the side, which is often observed when creating simplified devices.

A special frame for installing a chain saw bar increases the rigidity of the structure and ensures a stable position of the blade when performing work:

Attention! Having made a homemade tire sawmill, the master will receive a machine that will allow him to create a small individual production. It will make it possible to produce the necessary products and receive a certain income.

How to make a simple installation

Home master will be able to make a small sawmill for longitudinal sawing logs You need to have skills in working with a welding machine, grinder and electric drill.

Device design

Any work begins with a project. At the design stage, you need to decide on the main issues.

1. What will move? Tool or log? It is easier to install a guide along which you want to move the chain saw. If you specify the movement of a log, then it is necessary to create a powerful foundation for intermediate supports. The log pusher must overcome shear resistance and then maintain movement at a constant speed.
2. Which tool should I use? Gasoline or electric? If you plan to make a machine for home use, then you should focus on an electric saw. If it is necessary to create a mobile installation, preference is given to a gasoline saw.
3. What are the requirements for the quality of boards? If you want to obtain perfectly flat cutting surfaces, then you need to fix the blade in a special frame. For less stringent requirements, you can leave the free end without additional fixation.
4. How to fix a log? In practice, the material being processed is secured from the ends or sides. Each method has its own advantages and disadvantages.

End locking makes it easier to adjust the tree trunk before starting processing. Centering is easy.

The side fastening is more rigid, but requires time to position the log.

Having developed the basic diagram, the master works on the design of individual components. For complex elements, working drawings are developed, details are developed based on them, and the production of components begins.

It's time to move on to the question of how to make a tire sawmill with your own hands.

A variant of a tire sawmill in which the log moves. The tool is stationary during operation:

Step-by-step manufacturing of the installation

A small-sized sawmill will be manufactured. A Husqvarna chainsaw with an engine power of 3 hp will be used for production. To work you will need an aluminum folding ladder. It will be used as a guide to move the tool.

The sawmill is designed for processing logs brought from the forest. The option of using the installation directly in the forest is being considered.

Regular sanitary cleaning is required there. A lot of dead wood needs to be disposed of. The forestry department has been tasked with selectively removing old trees.

The Husqvarna petrol chainsaw has a standard bar with a working length of 38 cm. This will be used as the main tool in the installation.

Low weight and high power density, as well as a reliable gearbox, are the main criteria by which the tool was selected.

A support frame is welded from profile pipes with a square section of 25·25 mm with a wall of 2 mm. Her inner size is 400·400 mm.

The machine will be able to cut logs with a diameter of up to 400 mm. The corners of the frame are reinforced with gussets made of 4 mm thick strip. The corners are made of spring steel. Additionally, guides made of 30×30 mm profile pipes are welded to the frame.

Holes are drilled on the guides. M8 nuts are welded to them. The presence of such fasteners will allow you to fix the frame at a given height.

Special racks are equipped with clamps. They will hold the chain saw bar. The racks themselves fit tightly along the guides.

An example of installing a tire inside the rack jaws. The front and back are fixed on both sides.

You can secure the canvas in the jaws using bolts. For ease of operation, nuts of increased length are used. It will be easier to unscrew and tighten them for quick installation and dismantling of the saw blade.

Required condition for subsequent quality work installation is the perpendicularity of the jaws to the guide of the rack. Therefore, after manufacturing, the tire is installed in clamps and the quality of welding work is checked.

To prevent chain jamming, 4 mm thick plates are welded inside. The length of the plates themselves is 40 mm. The chain and tooth elements will fit freely between the inner plate and the clamping bolts.

The racks are installed so that the jaws are located below the elastic corners. This installation was thought out at the design stage of the device.

The parallelism between the racks is checked after they are installed in the guides. At this stage of assembly, the location of the canvas clamps relative to the frame must be controlled.

A drawing of the frame installation is presented, showing the main dimensions of the structure:

To allow the frame to move freely along the guides, furniture casters are used. They are mounted in such a way that the moving object is rigidly oriented in the vertical and horizontal planes.

Simple furniture casters with an internal bearing will move along the guides without displacement.

The aluminum ladder will be used as a guide support for making the sawmill. You can use one section, but if necessary, all three are connected. Then the working length of the formed lumber can reach 9 m.

Shows how to install the frame on the stairs. It is important to ensure that the side rollers are pressed. Then the frame will move without displacement.

The top and side rollers are tightly pressed against the aluminum guide. If necessary, the elastic corners can be shifted in one direction or another.

For longitudinal sawing, the chain of the tool must be changed. For transverse, a tooth with an inclination of 30⁰ and a pitch of 0.325” is used. For longitudinal – the tilt angle is 10 ⁰ and the pitch is 3/8 “.

The drive sprocket is being replaced. The replacement takes about two minutes.

Two different circuits are shown. Their differences are shown:

To be able to cut large diameter logs instead of a standard bar, an analogue from the “Partner” chain saw is used. The length is 600 mm.

First, a stand is installed near the saw.

Then the second rack is installed, located at the free end of the bus.

The frame is installed on top. Check the free movement along the guides. Only after making sure that the movement occurs without unnecessary effort, the jaws are fixed.

Attention! When tightening the jaws, do not use unnecessary force. The chain may become jammed.

Logs have different diameters and heights. The butt has a greater meaning. Further decreases.

To make parallel movement along the axis of the barrel, you need to place pads under the guide.

The log is mounted on trestles. A center search is in progress. Drawing with a pencil horizontal line.

You need to draw a vertical line. The center of the log is determined. Relative to it, other measurements and calculations will be performed.

A line is drawn along which the first cut will be made in the future.

Special backing boards are attached to the steps of the stairs. Metal clamps are used, they impart rigidity to the structure.

Self-tapping screws will be screwed into the log; they will create a strong connection between the log and the ladder.

For smaller diameters it is necessary to lay additional planks. They help produce a cut parallel to the axis of the log.

The position of the frame relative to the posts is set. Now the sawing will be performed with the specified plate thickness.

The machine is ready for use. All that remains is to start the engine and start cutting.

The cut to the specified length is completed. You can see the place where the cut was made.

All that remains is to cut off the plate. If necessary, additional sections are installed and the log will be sawn along its entire length.

View of the surface on which the chain saw blade moved. The whole structure was quite rigid. Therefore, an even flat surface on the back.

If it is necessary to obtain a long cut, the ladder links must be rigidly connected to each other. The usual three-section design will allow you to cut logs up to 9 m long.

You can start making lumber from existing logs. Even tree trunks that are uneven in different planes can be used for sawing. The timber and boards will have acceptable parameters.

The guide ladder is installed on a log. Sawing to the specified dimensions began.

It can be seen that the guide is located outside the log. The cutting and subsequent movement of the tire inside the wood will be carried out parallel to the surface of the stairs.

Since the length of the guide is greater than that of the log, the tool descends strictly along the stairs. The plane will be close to an ideal surface.

Cutting subsequent boards will be easier. There is a ready-made plane, relative to which the frame with the saw bar is oriented.

Now there is no need to install additional pads on one of the sides. Setup is much easier.

As a result of the work of the sawmill, boards are obtained that can be used in construction or for the manufacture of solid wood furniture.

A performance check showed that minor modifications and the production of guide devices made it possible to create a convenient machine for sawing logs.

According to the owner's review, this sawmill copes well with its tasks. In 6...8 hours, from the available logs, one user can prepare up to three cubic meters lumber. For a small-sized and budget instrument, the figure is quite decent. According to the manufacturer, the cost of creating the device was about 3 thousand rubles in 2017 prices.

The finished installation can be transported off site. Already at the site of deforestation, engage in the production of boards and timber.

Video: do-it-yourself tire sawmill.

Conclusion

1. Using an electric or gasoline chainsaw, you can make attachments that turn the tool into a sawmill.
2. A small machine can be adapted for work in the workshop, as well as on the road.

Wood sawing machine (saw bench) – quite complex special production equipment, requiring strict adherence to safety measures during operation. In the conditions of the Russian Federation, your own sawmill can significantly reduce the cost of wood construction and/or become a source of stable income. The purpose of this publication is to help the reader understand how to make a sawmill with your own hands, choose a suitable design for yourself and avoid insurmountable difficulties in its manufacture.

When is it needed?

Interest in the “do-it-yourself sawmill” actually came to RuNet from the EU. There, at a certain period of time (which has not yet completely ended), independent sawing of round timber into measured lumber turned out to be profitable no matter what. In the Russian Federation the situation is significantly different. First, price scissors wild log and timber in Russia have already been “divorced” a lot. Second, primary wood processing is a particularly dangerous job, just like logging. It is not realistic for a small individual entrepreneur to open a sawmill legally - Russian legislation on labor protection in this regard is draconian.

The third point is sawdust. There will be a lot of them from the primary processing of wood. Store sawdust (for example, for fuel for a stove) long burning) is impossible - they begin to ferment, releasing highly toxic methanol (methyl alcohol, wood alcohol). Sawmills are required to hand over sawdust for recycling. It’s easier with them “over the hill” - local MDF and fiberboard manufacturers will willingly buy the raw materials they need, maybe even with pick-up. The Russian Federation is not poor in wood and Russian manufacturers of slabs/sheets wood materials“left” parties do not take sawdust. Based on these conditions, it is possible to preliminarily determine cases when making a sawmill yourself in the Russian Federation may make sense:

• An indispensable condition is if round timber is easily accessible in your area, and the nearest sawmill is far away. Renting a timber truck for Russian distances (meaning idle mileage from the garage) on Russian roads in the outback is significantly more expensive per ton-kilometer of cargo than in Europe.
• If the indispensable condition is met, then the first case is independent wooden construction in the event of a chronic shortage Money. Then, independent sawing of round timber into timber will reduce the construction estimate by 2-3 times and up to 5 times, taking into account the costs of manufacturing a sawmill. Resp. The construction period will also lengthen, but when there is no money, there is nothing to choose. With sawdust - do what you want, they will turn out once.
• The next option is cutting wild logs to order at home, i.e. a foreman on call to the owner's yard. In the Russian Federation, this is probably best option: you can bring a mobile mini-sawmill (see below) to the place of work in a passenger car, so the cost of sawing is acceptable for both parties. Sawdust is the owner’s problem, and a small one, because... They are also thrown out to him on the site once. They don’t give the master a headache, i.e. you can register, for example. Individual entrepreneur as a carpenter and work “in white”.

Design Features

The main feature of the sawmill is that the cut in it is always longitudinal. It is well known how difficult it is to cut wood along the grain. Unlike a circular saw, a sawmill does not deal with measuring boards and beams, but with wild logs of generally irregular shape. Therefore, in sawmills, a saw carriage with a working element (the saw itself) moves along the log being cut; Otherwise, it is very difficult to ensure the accuracy and cleanliness of the cut. Large timber processing enterprises also have sawmills for sawing very long logs (up to 30, and in the tropics up to 60-70 m). In them, the carriage is stationary, and the log is moved by a hydraulic system; The centering of the line is ensured by a computer with sensors. But at home, such a solution is unrealistic.

Note: The sawing of logs is always carried out in the direction of convergence of the wood fibers, i.e. from the butt to the top. If you put the carriage in reverse, then any saw (see below) will certainly get stuck in the tree and/or break.

What to cut with?

How affordable, durable, convenient and safe to use a home-made sawmill will be is mainly determined by the design of its working part. Other essential condition– requirements for the productivity of the machine and its operating mode (regularly, occasionally). The third is the resource of the working body and the possibility of replacing it. And finally, the energy supply at the place of work is important: what is more accessible there – electricity or motor fuel? There are also less significant additional conditions, see below.

In sawmills with small and medium productivity (up to 3-5 cubic meters of wood per 6-hour work shift), the following are used. types of working bodies:

• Reciprocating saw bar (old).
• Saw blade (item 1 in the figure below).
• Saw band (item 2).
• Saw chain (item 3).
• Continuous chain saw bar (new, item 4).
• Household chainsaw (item 5).

How to drink?

The orientation of the cutting surface can be horizontal or vertical. Resp. and the cut will be horizontal or vertical, and the sawmill will be horizontal or vertical. Vertical cutting, firstly, reduces material waste, because It is enough to level the log under it only in the horizontal plane. When cutting horizontally, a log needs to be leveled both horizontally and vertically to minimize waste, otherwise too much wood will go into the slab (“hunch”). Secondly, when cutting vertically, the cut (the part of the log being sawed off) does not put pressure on the working part and clings to it much less. Therefore, to saw the same timber vertically, the drive power required is 2-3 times less than horizontally, see the video below:

Video: homemade vertical chain sawmill

But, firstly, the risk of injury with vertical sawmills is much higher than with horizontal ones. Secondly, the transverse feeding of logs under the saw of a vertical sawmill is structurally and technically very complex, and ensuring the maximum permissible sawing accuracy according to specifications of up to 6 mm per 6 m of log length on a homemade vertical sawmill is extremely difficult or even impossible. Therefore, it is better to build a sawmill with your own hands for a horizontal cut.

Structural composition of the sawmill

We’ll talk a little further about the features of a particular saw for a sawmill. First you need to understand the design of the sawing machine as a whole. It consists of:

1. working body - saw (see above and below);
2. drive to it from the motor;
3. saw carriage;
4. rail track (guide) for it;
5. carriage (cradle) for logs;
6. grip holders for him;
7. a frame that combines all this into a single device and ensures its overall strength and reliability.

Note: certain structural components of the sawmill can be made integral with the frame.

Sawmill drawings in full structural composition(layout diagram) are given in the figure:

Its features are, firstly, a frame made of wooden beams. Secondly, the minimum welding work during assembly. This important point: conducts metal structures during welding; Because of this, it is very problematic to specify the cutting accuracy of a welded sawmill. Thirdly, the carriage rail (item 13 on the right) is made of angle steel, cheaper than a channel; the necessary stability of the track is ensured by rigid fastening of the rails to the frame. As a result, the support shoes of the carriage are pairs of ordinary rolling bearings, and the smoothness and accuracy of its movement are high; trembling of the carriage is the main cause of sawing defects. Another consequence is the carriage feed mechanism without a gear (chain, screw, etc.), which also increases the smoothness of its movement. Finally, in a carriage of this design it is possible to install a drive with any of the saws listed above for horizontal cutting; disc, with a continuous tire and a chainsaw also for a vertical one.

The disadvantage of this machine is the comb log holders. It is impossible to make them from a channel less than 60 mm, as they will not hold the wood. That is, the last unusable slab will be no thinner than 60 mm. Additionally, material waste will increase because it is impossible to align the log vertically in this machine. However, it is not so difficult to get rid of these shortcomings by using a separate carriage for logs of a simple design, see below.

The operation of the cutting thickness setting unit (in the inset) requires some explanation, which in this machine is quite simple, accurate and easy to use. The nuts 5 in the insert are welded to the support plate 4 and locked. After the first cut, the adjusting screws (item 1 in the inset and 11 on the right) rotate synchronously, because they are connected by a chain drive (item 20 on the right). There is no need to loosen the locknuts (item 2 in the inset): they will loosen on their own. When the saw is installed in a new position below the previous one, the locknuts are tightened by hand.

Saw like a saw – longitudinal

A reciprocating saw bar is nothing more than a carpenter's rip saw blade. Its drawing, tooth profiling and wiring diagram are given in Fig. on right. The drive in the sawmill is from a flywheel to a crank mechanism through a slider - a smooth steel rod sliding in a cage with bronze or Babbitt liners (this is exactly what is shown in the figure above with the layout diagram of the sawmill). In former times, craftsmen used carpenter's bow saw blades instead of a saw bar; They also saw along, and you could buy them in almost any tool store. In this case, the tension of the blade during the reverse stroke is ensured by a fairly strong return spring.

The advantage of a reciprocating saw bar is a smooth, clean cut with a width of no more than 3 mm, i.e. low material waste. The resource is very solid, no less than that of a saw blade, see below. But there are also a lot of disadvantages:

• Low productivity: if the feed of the carriage during the reverse stroke of the saw exceeds 1/3 of the tooth height, i.e. 4 mm, the saw gets stuck.
• It is impossible to saw a log with a diameter of more than 300-320 mm - the blade immediately gets stuck and wrinkles.
• Damp, unseasoned wood does not take, it also immediately gets stuck and breaks.
• Very often gets stuck on knots and strands.
• If there is insufficient tension on the reverse stroke, the cut sharply worsens - it becomes wide and torn.
• The same applies to an excessively strong return spring.

In professional forestry, reciprocating saw bars fell out of use by the end of the 19th century, and among amateurs, with the advent of chainsaws in everyday life.

Disk

A saw blade from a circular saw will not fit into a sawmill: it is made of steel of poorer quality than required in this case. When sawing raw logs, the disk material from the circular saw will soon release itself due to heating, the disk will quickly fail or be completely blown apart. That's why saw blade For a sawmill, the pleasure is not cheap. In some sources you can find advice: they say, cut out a round piece from galvanized (!) or duralumin (!!!), attach 2-4 teeth to it, and saw. Judging by the fact that the authors of publications of this kind seem to be alive and not mutilated, they themselves did not do this and have no idea what could come of it.

Disc sawing of wood is widespread in professional woodworking because... allows you to cut several pieces of measured lumber from timber in one pass; For this purpose, angle and multi-disc saw carriages are used (inset at the top left of the figure). However, an industrial circular sawmill is complex structure, see fig., on the topic of “do it yourself” does not work.

If an amateur gets a sawmill blade (diameter from 600 mm, tooth profile the same as that of a rip saw, see above), he needs to keep in mind the following advantages and disadvantages:

• Long resource – up to 5000 hours or more; up to 1500-2000 hours between teeth regrinding.
• Required for sharpening sharpening machine, there is no way to do it manually.
• The cut is not very even, 3-5 mm wide, i.e. material waste up to 10-12% by volume. A “clean cut” disc, which produces a waste of 2-5%, costs 3-10 times more than a simple one.
• You can cut without any technical breaks for 6 hours. shift; Maximum performance in this class of devices.
• High energy consumption, because the disc rubs against the wood both vertically and horizontally when cut with the side surface large area. To obtain the required drive power in kW, multiply the diameter of the log in dm by 1.7.
• The quality and condition of the sawmill being processed have virtually no effect on the productivity of the sawmill.
• A disk with a diameter of 800 mm can cut a log with a diameter of up to 350 mm.
• Larger diameter discs in amateur designs are very dangerous, because... require a high-precision drive to avoid runout.
• The drive is only electric, because The disk should rotate absolutely smoothly at idle. In the tree he’s already got more than enough tugs.

In general, a DIY circular sawmill is definitely not an option. Let's look at the drawings in Fig. below. The first thing that catches your eye on the left is the carriage on rollers in channel rails. This is not a rail track made of milled profiles: a 1-2 mm misalignment of the rollers when moving the carriage is inevitable. The consequence is a disk misalignment of 6 mm or more. Right there he gets stuck in a tree. Considering the mass of the disk, its rotation speed and moment of inertia, the occurrence of an emergency and extremely traumatic situation is inevitable.

Next, the lower edge of the disk must fit into the groove of the log carriage, otherwise it will not finish cutting it to the end. And so, we sawed off the first top. What's next? In theory, you need several grooves in the carriage, depending on the thickness of the resulting boards. After each cut, either the carriage is raised, moved forward and lowered back to the working position, or the carriage with the log must be moved under it in the same way. Can you imagine such a design made at home? No need, your head will hurt a lot.

What if it’s simple? Just move the log on the carriage? No, it's not easy. It must be laid again so that the next cut runs exactly parallel to the previous one. And on the carriage there’s not a stick, there’s a huge, heavy block of wood.

Well, let’s say we have a strong family/staff, we don’t care about moving logs, and the loss of productivity due to this is acceptable. Then look at what is marked in red in the drawing on the right in Fig. Yes, this is a log holder. Without it, it will either roll off the carriage, or tip over when 2-3 blocks (unedged boards of the entire timber for cutting into measuring boards) are sawn off. The holder is located in the very middle of the log. You can't cut on it. In total, the most valuable, wide, strong and most evenly drying core block will most likely go to waste, because Due to the repositioning of the log, the thickness will be unacceptably converging on a wedge.

Note: an amateur single-disc sawmill for horizontal sawing is no more convenient or more productive than a vertical one, but its design is much more complex and dangerous.

So, making a circular sawmill with your own hands is an option in one and only case: if you have come up with an improvement to it that is a commercially promising invention and you need to test the idea in hardware in order to apply for a patent. In all other cases, it’s not necessary.

Band saw

The band sawmill is one of the inventions that produce significant results with trivial technical solutions. The reciprocating rip saw has a lot of advantages, and its disadvantages are due most of all to the presence of reverse motion. This means that you need to get rid of it in order to get a continuous saw blade. As a result, the operational properties of the band sawmill differ significantly from those of the prototype and machines for similar purposes:

1. Productivity – up to average, 2-3 cubic meters. m of wood per shift.
2. Saws both seasoned and raw freshly chopped round timber.
3. The cleanliness of the cut is as high as that of a rip saw blade, and the material waste is just as low.
4. The cutting accuracy is as high as that of a circular sawmill, provided that the saw blade tension is uniform and optimal.
5. It is impossible to saw logs immediately into pieces of measured materials.
6. Energy consumption per 1 cubic meter m of wood is 1.2-1.5 times lower than that of a circular sawmill.
7. To avoid self-release of the tape material, technical breaks in work are necessary: ​​after each wash for 5-10 minutes; after sawing 0.5 cu. m (2 logs with a diameter of 0.3 m and 6 m long) – 10-15 minutes; after 2 hours of work – half an hour to an hour; from 6 hour shift to next. the same - at least 2 hours.
8. The full resource of the working body (belt) is 100-500 hours; re-sharpening is not possible.
9. The cost of the tape per hour of work is much less than that of a simple saw blade.
10. The cost of the entire machine is several times less than a disk machine with an angular carriage per cut.
11. The drive is electric, because The idle speed of the belt needs to be as high as for a disk.

Due to these features, the band sawmill is most widely used in small sawmills. According to most advertisements: “We accept round logs/logs for sawing,” it is band sawmills that work. In Russia, band sawmills are produced in a fairly wide range (Taiga, etc.).

The simplest way to make a rip saw is to roll the blade into a ring and place it on pulleys, pos. 1 on next Fig.. To prevent injury from the non-working branch of the blade, a protective cover is put on the working part. Making a sawmill with a belt without it (item 2) is extremely dangerous!

The second stumbling block for DIYers here is the belt pulleys. The branded ones have a special slightly convex profile of the side surface (working surface). The belt slides off the cylindrical pulley; flanges (edges) do not help. Some craftsmen tilt the entire sawing unit upward by 1-3 degrees. However, as soon as the tension of the tape weakens (which is possible during one cut), the tape will fly off from above; without protective casing this is even more dangerous than sliding down.

Smarter craftsmen have found a way out: they put the tape on the wheels of cars and motorcycles with tires, pos. 3 in Fig. and rice at first. Their profile almost exactly matches the required one, and the elasticity of the tightly inflated chambers ensures optimal belt tension, at least enough to cut a whole log. In addition, if thin, high-quality materials are being sawed, then you can get by with a simple friction drive, also pos. 3 fig. on right. The manufacture of the machine is also simplified, because auto-moto wheels are already quite balanced, see video:

Video: DIY band sawmill

Transfer to saw

When sawing raw, untreated logs and knotty/twisty and sticky fine-grained wood, the transmission from the drive to the belt (the main one) is also a stumbling block. Mechanical characteristics The belt is too soft: the belt is elastic and can slip. Gear gear, on the contrary, is too rigid: for a moment before jamming, the gears give a sharp, strong jerk. In both cases, it is very likely that the tape will get stuck in the tree and become crushed, which immediately creates a dangerous situation.

The best final drive for a band sawmill is a chain drive. Idling It provides a belt almost as smooth as a belt. And when sawing “bad” wood, the chain’s own inertia pulls the tape with small, frequent jerks, and the inhomogeneities of the wood are successfully overcome. This is the same property chain transmission used, for example in screw wood splitters.

Chain instead of tape

The working body of a chain sawmill is a chain with saw teeth stretched on rollers. Its operational strength, service life and reliability (not prone to getting stuck on wood defects) are several times greater than tapes, and the cost per cut length before wear is lower. The saw chain can be re-sharpened (you need a sharpening machine!) and does not require any technical breaks during the shift. The drive can be energy-independent from a 1-2 cylinder 2-stroke internal combustion engine: saw chain itself dampens its vibrations. In terms of safety, the chain sawmill is the best in this segment of production equipment.

Disadvantages: firstly, increased energy consumption compared to tape - the chain casing rubs against wood, although not as much as the disk. The second is a wide (4-6 mm or more) rather ragged cut: lumber from a chain sawmill needs sanding (that’s why a surface grinder is not often built into it) or will be sold as a second grade. Consequence: increased material waste, up to 15% by volume. Third, in continuous operation it is necessary to supply coolant (cutting fluid, emulsion) to the saw chain, see fig. The fourth is a long technical break between shifts for self-healing of the chain properties: at least 10 hours. And, finally, the high labor intensity of maintenance: re-sharpening and/or replacement of chain teeth is required every 10-50 hours of work, and fiddling with them - mom, don’t worry!

Due to these circumstances, chain sawmills are used primarily. for primary sawing of timber at stock exchanges and harvesting sites. In the latter case, the energy independence of the machine with an internal combustion engine plays a decisive role: it is brought in by truck or tractor, the wood is unraveled onto the blocks and taken away. In remote regions of the Russian Federation and Canada, wood losses are often more than compensated by savings on round timber transportation by timber trucks. But this approach, of course, does not benefit the forest as a living community. Both from excessive cutting and from clogging with sawdust.

New tire

The continuous saw bar is a cantilever chain saw, i.e. does not require tension at the end farthest from the drive; it also does not require coolant supply. Do you recognize? This is the “blade” of the chainsaw. Application modern materials and continuous improvement of the design made it possible to create chainsaws that are suitable in all respects for domestic use. A sawmill made from a chainsaw at home is also much easier to make than any other; drawings of a frame with rails and a log holder can be taken, and carriages for a household chainsaw. Its performance qualities and features (except for the resource) will be approx. the same as for a chain sawmill. Changeover from horizontal to vertical cutting is carried out simply by rearranging the carriage. But please note:

• The service life of the saw motor will be reduced by approx. doubled.
• Full canvas resource best models will be no more than 20-30 hours, and cheap ones - 10-12 hours.
• Every 2-3 hours you will need to re-sharpen, and every 4-6 hours you will need to replace the teeth (if possible for this sample).
• The total operating time during the day is 2-3 hours.
• Maintenance break until next shift – from 12 hours.
• The saw must be designed for both transverse and longitudinal cuts.

The last circumstance, as Comrade Sukhov would say, is a delicate matter. Models from leading manufacturers (Stihl, for example) have both cuts provided by default, but the resource for the longitudinal one is given for normal use: 15 minutes of work, half an hour of rest. It is impossible to withstand it in a sawmill, because... You cannot stop the carriage while cutting is in progress. In this case, the resource of the saw bar is reduced by half or three times. “Alternative” manufacturers often have the opposite: the default saw is only a cross-cut saw. If the user manual says “transverse and longitudinal”, “also longitudinal”, etc., then the resource for a longitudinal cut is not specified. Keep in mind.

Special continuous saw bars are produced for sawmills. Due to the refusal of a transverse cut, their offset (length) is greater, up to 1000-1200 mm, the cut is thinner (3-4 mm) and cleaner; virtually the same as a band saw. The resource and mode of use are the same as those of a saw chain. A sawmill with a tire can be of a conventional design (on the left in the figure), but in the context of homemade ones, the Logosol type tire sawmill, center-right in the figure, is of much greater interest. Spring edge supports keep the log from rolling away. The elevators are adjusted separately, which allows you to level the log horizontally.

The history of Logosol is interesting and inextricably linked with ours. In the USSR, since the 30s, the export of unprocessed wood was strictly regulated and produced in large quantities through established channels. After its collapse, the former Soviet republics, which had forest reserves, literally flooded Europe with cheap round timber, with standards equal to the size of a log. In the EU, the main domestic logging is carried out in Germany and Switzerland in the Alps. There are plenty of smart woodworkers here and there, and they are accustomed to working with an acute shortage of raw materials. Given the prices for timber there, calculating the income from the purchase of wild timber and sawing it into boards in one’s yard gave results that made one’s eyes pop. Plus - there is no headache with disposal of sawdust, but there is a significant additional benefit from selling it. It was then that the Swiss Bengt-Olof Byström came up with a sawmill, which he called Logosol. Its highlight is the replacement of a technologically complex rail track with a smooth guide along which the carriage is moved manually with a clamp. This requires more labor and some skill, but the design of the sawmill is greatly simplified, and its cost drops significantly. Hobbyists have developed many modifications of Byström's undoubtedly successful design. Their drawings of Logosols and components for them can be openly taken from here: //www.logosol.su/files.htm. How to make a Logosol sawmill with your own hands, see the video:

Video: DIY mobile-stationary Logosol “Terya”

The appearance of Logosol is the direct reason for the development of saw bars for sawmills. There are models available for sale that are compatible with household chainsaws: remove the standard blade and install the bar. Thus, the issue with the cost and labor intensity of the drive was resolved: a chainsaw on the farm is already a necessary thing.

Mini

A further development of Logosol’s idea is a mini sawmill without a frame, guide and rails, see fig. on right. Instead of a guide, an existing saw cut is used; with careful manual sawing its accuracy within the log is maintained. In this case, in addition to the tire and drive, only the support platform and handles for holding and moving.

The pioneer cut is made according to a template (a flat board, top right in the figure), a channel, a frame from an angle, etc., longer than a log. Subsequent horizontal ones are the same as the previous one, in the center on the right. If a vertical cut is necessary, place a channel (bottom right), because in this case, a flat lateral supporting surface is needed. However, this does not eliminate all latest problems: installing a log on a carriage, leveling it and holding it.

Carriage, grips, clamps

There remains such a problem as a frame with additional components. The one on pos. 1 pic. the left is far from optimal. For one-time sawing for self-construction, it is too complex and expensive. It is also not suitable for long-term regular use: even if the supporting frame is made of a 200 mm channel, it will not sag after the first or second dozen logs, which means the machine is completely unsuitable. A stationary sawmill should be made with separate concrete rail tracks and a carriage for logs (item 2; in this case we will not focus on safety precautions - the topic of this article is different).

The next tasks are leveling and holding the log. In industrial woodworking they use hydraulic jacks in hooks. The log is hung on the hoist, lowered onto the carriage without touching it, the jacks turn on and grab it tightly. In automated carriages, a log is placed on it and hydraulics, based on sensor signals, immediately levels the timber.

In amateur conditions, the first is not feasible; the second is in no way feasible. In many homemade sawmills, log grippers are made as shown in Fig. below. The log is hung on automatic jacks (see below), hooks are brought to it, sliding along a guide (pipe, thick rod). The hooks are tapped with a hammer according to the principle of “lightly tapping with a sledgehammer”, they are wedged on the guides and hold the log.

Firstly, such fastening is simply dangerous: vibrations during sawing can cause the grips to become wedged, and this is an accident most likely with serious consequences. Secondly, it is impossible to grab the wood by the very “bottom” in this way. This means that you will have to turn the log over before finishing it halfway. As a result, the cutting quality and material waste will be the same as on a vertical single-disc sawmill, see above.

Carriage

Let's try to develop technical requirements for a log carriage suitable, incl. for use with a portable mini sawmill when working on the road:

1. materials – ordinary rolled metal without preliminary screening for evenness;
2. for strength, reliability and durability - welded;
3. the influence of the quality of welding and warping of the metal from it on the quality of sawing is absent;
4. prepared base (support) surface – not required;
5. weight and dimensions - suitable for transportation in a mini-truck, pickup truck and on the top trunk of a car;
6. the maximum length of the processed log is 6 m;
7. its maximum diameter is up to 1 m;
8. leveling and hanging the log - in any way independent of the carriage, see below;
9. the influence of the flatness of the carriage along the horizon on the quality of sawing - no;
10. the reliability of holding the most clumsy, unrooted forest is absolute;
11. the ability to dismantle the sawn blocks into edged measuring boards/beams without readjusting the sawmill - a must;
12. security – sufficient for non-production conditions, when access to the site of untrained outsiders is easily controlled.

Drawings of a log carriage for a sawmill, incl. mini, satisfying specified conditions, are given in Fig. (left/center – top view). Material – channel 120x60, rod 14 and 16 mm.

Exactly under the M14 holes in the upper flange of the channel, D15 holes are drilled in the lower flange for the passage of the shanks of the hook holders (on the right in the figure). The M16 holes in the bottom shelf (marked in green) are for threaded feet. The plan configuration and location of the grip holders make it possible to reliably hold both full-length logs and short logs. Use this carriage like this:

• the log is hung and leveled on a pair of auto jacks. An option is to use one jack at a time: put something suitable under the raised end, rearrange the jack and lift the other one;
• the carriage is slipped under the middle of the log with the widened part towards the butt and aligned along the axis of the timber. If the log was hung on a hoist, then the middle pair of legs should fall under its center of gravity;
• the holder hooks are turned out until they touch the log so that their points look inward exactly at each other. A slip by one turn (by M14 thread pitch) does not affect the cutting accuracy;
• the log is lowered onto the hooks. If the timber was hung on one jack and a support, then first release the jack, and then knock out the support with one sharp blow;
• to securely hold a thin light log, you can sit on it and jump;
• saw the log using any sawmill using horizontal cuts. The thickness of the last slab in the vast majority will not exceed 40 mm.

Clamps

Full functionality of this carriage will be ensured by 2-5 clamps (3 are almost always enough) for sawing blocks into dimensional lumber. The design of the clamp to the log carriage is clear from Fig. below. The clamps are bolted into the standard holes of the M14 carriage, so their bases and the distances between the axes of the mounting holes are different: unlike the hook holders, the clamps are not interchangeable! Before dissolving into boards/beams, the logs are first sawn into blocks. Then the blocks are sorted and collected into packages of blocks of a similar configuration to each other. The next package is clamped with clamps on a gun carriage and cut into boards/beams using horizontal cuts.

Bottom line

Let’s take a look, as they say, at a grandma: what kind of sawmill to make with your own hands and in what cases does it make sense.

If you see a range of clients for sawing and/or see a stable income from the sale of lumber - a band on motor-wheels. It will last at least until you have enough money to buy a “new, good” factory one. Then it will be possible to open a sawmill in its entirety and calmly work legally. If sawing wood is a side hustle for you, the Logosol sawmill will perform better - it is less productive, but structurally simpler and cheaper, and a chainsaw will come in handy on the farm anyway.

The modern construction market is overcrowded various models tire sawmills, differing from each other both in price and quality. However, it is not at all necessary to purchase ready-made woodworking equipment, because a tire sawmill can be made with your own hands. It won’t take you too much time and effort, but the result of this work will delight you for many years, because a do-it-yourself tire sawmill will serve you just as long as a model made by a well-known company.

The sawmill is an indispensable tool when processing wood and building from this material.

The tire sawmill is an indispensable woodworking equipment for many residents of our country living in small towns or villages. Every rural resident is well aware of the huge role this equipment plays when performing wood processing work.

To make a sawmill you will need two channels 8 m long and 0.14 m high

A self-made tire sawmill will become a reliable assistant when performing household work. Do-it-yourself is quite simple; for the production of the frame the following are used:

• two steel channels having a length of 8 m and a height of 0.14 m.
• rails;
• in some cases, metal corners.

It is very important to ensure that all your workpieces are perfectly straight, otherwise your equipment will not function properly.

1. In steel channels along their entire length it is necessary to make holes with a diameter of about 15 mm at a distance of no more than 1.5 m.
2. Next, depending on the number of these holes, you will need to make special couplers. You can use pieces of metal water pipe as material for them.
3. After everything finished parts must be securely fastened using threaded rods or regular bolts.
4. Now all the components of the structure of the future sawmill with your own hands, which you have previously prepared, need to be collected in one place, and then installed on racks.

The number of racks directly depends on the size and length of your sawmill. It is important to remember that the end posts must be placed at least 1 m from the end of the guides.

Read also:

Manufacturing and installation of the trolley

Construction of a sawmill.

In order to give the structure of the sawmill the necessary rigidity, you need to securely fix the braces. After this, install a movable cart on it, for the manufacture of which a steel plate is used. To do this, its thickness should be from 4 to 6 mm, and its length should be approximately 60 cm. However, the parameters may be different, depending on the size of the electric motor itself. For the finished sawmill cart, you will need to select clamping plates and some spacers.

These elements are necessary to ensure free movement of the entire trolley mechanism in DIY tire sawmills. But at the same time for normal operation equipment requires the minimum possible clearance. To tighten the gaskets, you can use regular bolts. Next, you will need to eliminate the lateral play, for which you should simply attach the stop angle to the sawmill cart. It should be noted that this trolley can be installed either on rollers or on bearings.

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Features of the tire sawmill engine

Pressed onto the motor shaft (usually electric) aluminum profile, which has two belts. While the engine is running, the force from the motor is transferred through two belts to a pulley, which is located on the cutting bracket. All pulleys located on the outer edge must have a diameter of 80 mm. If you have a walk-behind tractor, you can take them from there. Through the driven pulley, the engine force is transmitted to the roller, which rotates on two bearings, then to the sprocket and finally to the saw chain.

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Do-it-yourself saw chain on a sawmill

Saw unit and operation diagram of the sawmill.

The chain is used to move the metal cart on which the saw and the sawmill motor are located. It is very important to ensure that the chain is not tensioned very well. The required tension of the sawmill chain and belts can be easily adjusted with your own hands, simply fixing it with two bolts and nuts. In addition, in addition, you can also install a special tension bolt on the sawmill chain tensioner; however, as practice shows, the force of the pliers is usually enough to ensure that the equipment chain is always tensioned very well. To ensure easier and longer operation of the chain, it is recommended to regularly lubricate it with machine oil.

The sawmill steering wheel should be mounted directly on one of the sprocket bushings located at the edges of the guides. Next, you need to start making a device for fixing the log. For this purpose, special movable rods are inserted into pipes with a diameter of approximately 30-40 mm, which are inserted into the stopper at the desired level with an M8 screw. Next, you should attach the necessary pressing parts (they should be about 1.5 cm long) and cam clamps on top of these rods.

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Do-it-yourself installation and use of a tire sawmill

Drawing the simplest sawmill made from a chainsaw.

Now that your DIY sawmill is completely ready, you can begin its installation. To do this, the sawmill should be installed on guide rails using four support rollers. It should be noted that these rollers are often converted from walk-behind tractor tensioners. When installing a sawmill, it is very important to remember that the tires and saw chain must be designed only for longitudinal sawing. Make sure to keep the chain very sharp so you can cut the wood much faster. For normal operation of the sawmill, you will need to change at least two chains within one day.

So that you can set the thickness of the cuts you cut wooden planks, you need to install a special vertical screw. When it rotates, the frame with the saw unit will move either up or down, according to your needs. At first, you can only set the exact size of the board using a ruler. However, later, when you become a truly experienced framer, you will easily set the thickness of the blanks you need, just by focusing on the turns of the screw.

Our clients have repeatedly asked about high-quality drawings for tire sawmills. Basically, all their questions can be combined into several particularly important ones:

• Is it possible to download a high-quality drawing of a sawmill from your website?
• Can I do homemade sawmill based on your drawings?
• How much will the drawings of your sawmills cost?

Our answers:

• You can download drawings from this page for informational purposes. The fact is that the drawings of the Murka tire sawmills are our own and therefore secret production development. The drawings below are the first prototypes of tire sawmills.
• Of course this is possible, but artisanal conditions You will not be able to obtain a structure with the required rigidity. High quality material It's not cheap. Well, probably one of the main disadvantages self-made- these are terms that can sometimes be extended for six months or a year.
• A complete set of high-quality drawings and documentation costs 15,000 rubles, provided that you use the sawmill for your own purposes without distribution rights. It is possible to sell drawings with the right to distribute and use for commercial purposes. The price is around 40,000 rubles, negotiated individually.

Drawings of the Murka bus sawmill

All the drawings of the sawmill and its individual components and parts presented below can be viewed or downloaded. To download, you need to right-click on the link of the drawing you are interested in and select “save to download folder”, “save object as..” or similar, according to your browser.

Don't make a sawmill like this. During the production process, shortcomings in the design of the mini sawmill were identified and eliminated. The sawmill, assembled with our own hands according to the drawings proposed above, has the following disadvantages: heavy weight and long production time, we went through all this by trial and error. These drawings do not provide a guarantee or accuracy in the manufacture of the sawmill. Alternatively, you can look for a used sawmill, but no one will give you a guarantee of its long service life. We provide a 2-year warranty on our sawmills. Therefore, make the sawmill the most in a simple way- buy it on the website. Woodworking machines can also be ordered on the website www.sibpilorama.info. You can sell a sawmill after building a house, but a mini sawmill will always come in handy on the farm.

3D models of tire sawmills

Below are several 3D models of Murka tire sawmills, general view. When you order a set of drawings, you also receive three-dimensional models of the sawmill and documents.

Jokers can say this: “Repairs cannot be completed, they can be temporarily suspended.” Irony comes in very handy here, since an economic person always has a reason and desire to build or improve something. There would be time for this, and building materials. The building materials market is saturated to the limit. But their prices can hurt your wallet.

The difference between a homemade tire sawmill and a conventional one is that the cutting element here is a tire and a chain from a chainsaw.

And if you think about it, you can make some of the materials yourself. You can definitely prepare lumber yourself. It is enough just to make a tire sawmill.

Required tools and materials

The tire sawmill does not have any special design tricks. It differs from an ordinary sawmill in that the cutting element here is a tire and a chain from the most ordinary chainsaw. The first versions of such sawmills were made on the basis of a chainsaw. Currently, craftsmen recommend making sawmills using more powerful gasoline or electric engines. Preference should be given to internal combustion engines. In this case, the sawmill will not require an electrical network and can be used away from communications. You can cut logs directly in the forest.

To make a tire sawmill you will need:

• metal channels;
• tubes (it is better to have rectangular tubes);
• bearings;
• engine;
• two pulleys;
• pulley belts;
• gearbox;
• chainsaw tire;
• electric welding;
• drill.

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Assembly order

First you have to assemble the cutting machine. For a tire sawmill, a frame is made that resembles a cube frame. The chainsaw bar should be located in the central part of this frame. The tire must be secured on both sides.

The driven sprocket is usually mounted on a vertical holder. The opposite part of the bar is attached to elements that allow you to adjust the chain tension. But this is optional.

It is better to securely fix the tire, and organize the chain tension by moving the drive sprocket. This is not difficult to do: the drive sprocket is attached to the gearbox shaft, which is mounted on a metal base with longitudinal slots. It will be enough to simply release the fasteners and move the gearbox in the required direction.

We connect the gearbox drive shaft to the pulley (to a key). The second pulley will be located on the engine. The place for mounting the motor must be organized so that nothing interferes with the movement of the sawmill cutting machine. Rollers are used to tension the belts. The design of the belt clutch may vary. It is not necessary to make this element yourself: any design from agricultural machinery will do.

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How to adjust tire height?

And now you have to think over a system that allows you to adjust the height of the chainsaw bar above ground level. The simplest solution would be to place the entire cutting machine on vertical stands. For this purpose, two pipes are used, on which are cut pipes of larger diameter. Movement should be free, but without play. The outer (movable) tubes have holes to which nuts are welded. By screwing the bolts into these nuts until they stop, you will get a reliable fixation of the height. For convenience, notches can be made on the supporting posts at a distance of 1 cm from each other. Thus, you will be able to accurately determine the lowering height of the cutting element of the sawmill and obtain lumber of the required dimensions at the output.

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How to arrange horizontal movement?

Now let’s solve the issue of moving the entire sawmill along the log. Unlike usual band sawmills, where on cutting elements the log is fed, the sawmill itself must move along the line of the intended cut. Vertical racks To do this, they are welded to a metal base, in the lower part of which wheels (or bearings) are located.

There are chainsaw-based sawmills that move on rails on corresponding wheels. This perfect option, since there is no need to invent anything. In reality, it will be difficult to find all the elements to create such a movable sawmill base. More often, metal wheels are used that move along guides. U-shaped channels are used for guides. The wheels in this design must be adjustable in height (minimum 2 adjustable wheels). This design of the sawmill base will allow all support points to be located in the same plane.

The guide channels must be welded together into a single structure. You can also make a collapsible design of the guides, then the bus sawmill can easily be dismantled and delivered to the place of intended sawing.

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The importance of secure fit

Now you need to take care of fixing the tree. To do this, you will also have to arrange a small structure. Usually a metal base is welded from two corners (a 5 by 5 corner section can be considered optimal). At the bottom of this structure, you need to weld a stop that has spikes in the direction of the tree. They will keep the tree from moving in any way.

In the rear part of the structure, the same stop is needed, but with a movable base (along the line of the log). This stop will allow you to cut logs of various lengths. Spikes can be made from ordinary bolts, passed through the holes in the stop and secured with nuts with inside. Then the bolts are simply sharpened.

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Design Features

We can assume that the tire sawmill has acquired its final appearance and is ready for sawing wood. Don't rush and don't expect to do everything perfectly quickly and accurately. The sawmill must undergo further testing, and the operator must learn to work on it. On this path, certain negative aspects may await you:

1. The tire sawmill is heavier at the top. The center of gravity at a high altitude causes strong deviations in the direction of the tire. The lumber will have a noticeable “waviness”. The vibration is felt very strongly by the operator. There are two options: either place the engine lower from the sawmill, or increase the weight of the lower part.
2. The sawmill moves along the guides only with great effort from the operator. If the wheels of the sawmill do not have excessive friction with the guides, then the cause of the inconvenience lies, again, in the location of the center of gravity. The design needs a counterweight to the engine.
3. When sawing, the chain stops. A common occurrence when the clutch is adjusted incorrectly. You just need to tighten the clutch rollers or shorten the cable.

Initially, tire sawmills were made on the basis of a chainsaw.

This caused a number of serious inconveniences. Feeding wood and operating the chainsaw accelerator was only possible with the participation of two people. The design of the sawmill described above allows one person to work successfully on it. Moving cutting part sawmills, the operator sees all the moments of sawing and can independently adjust the speed of feeding the tire onto the tree trunk. Typically, it takes about 5 minutes to cut a 4-meter log. A chainsaw will do this job a little faster, but the quality of the cut will not be as smooth as when using a tire sawmill.

A chainsaw sawmill can have a stationary tire arrangement. In this case, the log itself is served. It is not necessary for several people to be present. Supply is ensured through the use of chains from agricultural machinery. Such a chain is fixed to a movable cart on which the log is located. The chain is attached to sprockets, one of which should be located next to the operator and have a handle for rotation. Such homemade products work no worse than others. The only drawback is that such tire sawmills require additional load on the person’s hands and certain sawing skills.

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