Homeowners who heat a dwelling with a wood boiler or stove have to harvest 4–12 cubic meters of logs annually. Sure, exercise is good for your health, but chopping with a hand ax takes too much time. There are 2 ways to speed up the cutting process: buy a mechanical cleaver for firewood or save money and make a wood splitter yourself. Consider options for homemade appliances and the technology for their manufacture.
Choosing a wood splitter design
First, recall what a cleaver for firewood is. This is a modified ax with a long handle (about 0.8 m) and a heavy blade sharpened at a relatively obtuse angle - 30-35 degrees. The design is designed for splitting wood along the fibers, this tool is not suitable for conventional chopping and tees.
Reference. The weight of the “head” of a traditional hand cleaver with a long ax is in the range of 2-3 kg.
Mechanical splitters inherited some of these characteristics, which we will discuss later. Today, households use 3 types of factory-made devices and home-made analogues:
- spring with a manual drive;
- electric - screw and rack;
- hydraulic.
We suggest that you consider the design of mechanical splitters and find out which device is best done based on the volume of splitting and the cost of components. If you want to cut many small branches, then it is better to make another machine - a wood chipper.
Spring tool with lever
The splitter options shown in the photo consist of the following elements:
- frame made of metal profiles or pipes with horizontal supports;
- long arrow - a lever mounted on a hinge;
- from the hinge side, the arrow rests on a spring inserted between two cups;
- at the end of the lever is fixed the load and the blade of the cleaver plus a handle is made for a comfortable grip.
Note. The frame design is optional. The main task is to prevent the mechanism from tipping over during the decking process. Sometimes the end of an arrow is embedded in a wall or attached to various house structures.
The principle of operation of the wood splitter is based on the amplification of the impact due to the elasticity of the manually extended spring. A stand is placed under the blade at a convenient height, where sawn decks are installed. The operator swings the lever with one hand like a pendulum, the second moves the tree under the blows of an impromptu ax.
The advantages of a spring cleaver made of metal with your own hands:
- simplicity and minimum price of materials for the manufacture of devices;
- the operation of the mechanism is independent of electricity;
- due to the frequent fluctuations of the lever of the deck, it is easy to chop wood for any size - from torches to logs, the main thing is dexterity.
The main minus of the splitter is the danger of slipping fingers between the oscillating blade and the block during the rearrangement process. Well, the second point: the mechanism does not exempt the homeowner from hard physical labor - you need to swing the arrow, quickly move the deck and remove firewood.
Comment. It is much more difficult to chop knotty scraps and “slingshots” - you have to strike several hits at one point.
Electric models
Mechanized splitters - screw and rack, powered by an electric motor, greatly facilitate the work of the cutter. But the cost of these wood splitters increases due to the use of motors, drive parts and a special splitting tool:
- The main chopping element of the screw model is a metal cone with a large thread cut to the side opposite to the rotation of the shaft.A spinning “carrot” with its tip captures the deck, cuts into the thickness of the wood and breaks it into 2 parts.
- The rack and pinion transmission is the main element of the second design with an electric drive. The principle of operation resembles a car steering rack - the block is mounted on a fixed blade of the cleaver with a pusher attached to a gear steel rack.
Reference. In the rack model, one detail of the traditional cleaver is used - a blade pointed at 30 °. By the way, instead of an electric motor, you can use a suitable single-cylinder gasoline engine or connect the power take-off shaft of an agricultural walk-behind tractor.
Assembling an electric wood splitter will require the cost of manufacturing key parts - a threaded “carrot” or a rack with gear. If the electric motor, drive pulleys and metal rolling can be found in the household, then the cone element will have to be ordered by the turner, and the gear rack - by the milling machine.
From the point of view of labor safety, a rack and pinion machine is preferable, since rotating parts are under the frame, it remains only to take care of your hands. Problems happen with a screw splitter - the cone easily captures and instantly winds up the elements of clothing. When operating the unit, care must be taken.
Hydraulic cleaver
This design is considered expensive for self-manufacturing. In addition to the support frame, the splitter consists of the following functional elements:
- electric motor rotating oil pump;
- hydraulic cylinder with high pressure hoses;
- manual shift force distributor;
- tank with oil and filter;
- an iron pusher screwed to the cylinder rod;
- the blade of the cleaver is usually cruciform.
The work of the unit is built on an effort of 4-10 tons, developed by hydraulics, which allows you to split the block immediately into 4 logs (you can do more). The drive action algorithm looks like this:
- After starting the electric motor, the pump raises the pressure in the system to the desired value. Excess oil is discharged by the distributor through the return line to the tank.
- When the operator presses the control knob of the dispenser, fluid is supplied to the cylinder and presses on the piston. The latter moves the pusher along with the deck to the blade.
- After splitting, the operator switches the unit to another mode and the oil begins to press on the piston on the other hand, coming in through the second hose. The rod and pusher moves back.
Operation of a hydraulic splitter minimizes physical labor - the cutter only needs to lay the tree on the bed and turn on the drive. The risk of injury is quite low - the operator’s hands and clothes are far from moving parts of the machine.
Selection recommendations
The most difficult is the assembly of the rack and pinion mechanism - you need to find or grind the gear train and the guides along which the pusher will move. In addition, you need to accurately select the rotation speed and gear ratios. Other versions of chopping devices are made somewhat easier.
Choose a cleaver design depending on the working conditions, materials available in the farm and the budget allocated for the purchase of components. Our recommendations:
- In the country, where electricity is absent or intermittently supplied, it is better to make a simple lever splitter. Financial costs are minimal.
- The second place in terms of simplicity is taken by a screw machine. If you want small mechanization with small investments, order a cone element and look for an electric motor with a power of 1.5-3 kW.
- A device with a hydraulic drive will greatly help homeowners of old and retirement age. The difficulty lies in acquiring a set of hydraulics - a pump, a cylinder and a distributor.
Note. We specifically did not mention the oil tank - it is easy to weld a metal tank of the required volume yourself or to find it ready-made.
How to make a wood splitter on a spring
We already wrote above that the frame design is chosen arbitrarily, the main thing is stability. But before you make a lever, you need to calculate the main dimensions according to the distribution of effort. The task is to achieve the perfect balance between the length of the boom, the mass of the load at the end and the distance from the hinge to the spring. The mechanics of this system is described by the equation:
- M is the mass of the counterweight at the end of the beam, kg;
- F is the spring force;
- l is the distance from the hinge to the spring, m;
- L is the total length of the lever, m
If you neglect the calculation, then 2 scenarios are possible: you will have to make a big effort to swing the arrow or the cleaver will hit very weakly. Physical meaning: the farther the spring is from the hinge and the higher its stiffness, the longer the lever and the mass of the load will be required.
An example of determining the main dimensions of a beam. We take the spring from the Zhiguli car, which compresses with a force of about 200 kg (the weight of the machine is 0.8 tons), and we move it away from the strut by 30 cm. We calculate the remaining indicators by the selection method - we take the boom length of 2 m, then the weight of the load is 30 kg, including the mass of the cleaver and lever. Check: 30/200 = 0.3 / 2 = 0.15.
To assemble a lever splitter, use simple materials:
- spring from a small car (VAZ, Tavria and the like);
- a finished blade from a manual cleaver or a billet of low carbon steel with a thickness of 20 mm;
- pipe according to the diameter of the spring - for the manufacture of cups;
- various metal products for the frame - corners, pipes round and profile with a wall thickness of 3 mm.
Tip. As a hinge, it is not necessary to use a shaft on bearings, this is an excess. The mechanism is quite rough, so a simple articulated shaft-sleeve pair will fit, as shown in the photo. Similar details are placed on the garage doors as awnings.
The assembly process is quite simple and does not require a detailed description. Based on the drawing, weld a stable frame, make cups and install a spring with a lever. At the end, attach a load and a splitting blade to the beam.
We assemble the screw and hydraulic apparatus
To greatly simplify the design of the cleaver will help a suitable engine with a speed of 500 rpm with a power of 1.5-2 kW. Such an electric motor fits directly with the cone, you do not have to put a belt drive. If the unit with these characteristics could not be found, prepare the following set of materials:
Recommendation. Do not order a turner screw "carrot" until you know the diameter of the driven shaft or the main shaft of the engine. The thread of the working cone is performed with two passes, the steel grade is St35 ... St45 (high carbon).
From metal profiles it is necessary to weld a table, fix a sheet of metal on top. The motor is mounted on a plate under the countertop, the secondary shaft with a cone - at the top. The pulleys are placed on the dowels or fixed with locking screws. When connecting the power cable, take care to ground the unit.
An important point. When chopping wood with a screw device, you need to correctly slide the block to the tool - strictly in an upright position. If you lay it on its side, one log will be stuck between the cone and the countertop.
The assembly of the hydraulic splitter differs in the installation of equipment. Instead of an electric motor and a carrot, you need to install a blade, a plate-pusher and a working cylinder. Note that the rest of the components can be placed separately by bringing high-pressure hoses to the cylinder from the hydraulic pump.
A very detailed and intelligible process of manufacturing a hydraulic unit is shown in the video:
Finally about hand axes
If you do not have the opportunity to make a mechanized wood splitter yourself, you will have to chop wood in the traditional way. It is important to choose a convenient tool that will facilitate the work as much as possible.
How to choose axes for splitting firewood:
- The shops sell cleavers with different stick lengths and blade weights (2-5 kg).Get a tool that suits your physical form, because you need to wave an ax often and for a long time. Do not immediately take the heaviest specimens.
- A wooden hatchet of quality products is trimmed from elm, maple or birch. These rocks do not crumble into chips and do not crack.
- Do not buy an ax with a handle that is too short to reduce the impact force. Too long an ax is easily trimmed to the desired size.
- Make sure that the “head” fits tightly on the handle.
If the budget allows, it is worth paying attention to more practical imported splitters with a durable plastic handle and various blade profiles made of quality steel. Popular options are Fiskars brand direct axes and firewood splitters with a shifted center of gravity from Vipukirves.