Construction of the saw
Saws can be an independent tool or be part of another device. Devices that use a saw as a working element are called chainsaws. A characteristic feature of the saw has a serrated working blade for cutting or another shaping (carving) of materials such as wood, metal, or stones. Saws can be powered by hand, by the power of human muscles or mechanically – electric or internal combustion engines.
The saw blade is called the saw blade and is an essential part of the tool. Usually, it is placed in holders or various types of housing in order to facilitate work. Hand saws can be equipped with one or two handles, and the saw blade can be mounted on a handle, but also stretched on a frame or bow.
Sawteeth can have a variety of shapes, e.g., arched, wedge-shaped, or square – should be selected depending on the type of material being processed, cutting direction (lengthwise, crosswise), as well as the required cutting precision. To strengthen tooth durability, they can be locally hardened or coated with sturdy materials (cemented carbides). Unlike typical saw blades, so-called circular saws that have blades (teeth) located around the circumference of the wheel.
Types and use of a hand saw
Compared to power saws, the advantage of hand saws is much higher safety at work and a much lower price. However, their disadvantage is much lower efficiency and the need to put more effort into the cutting process.
Depending on the application, we distinguish:
– general-purpose saws – for both wood and plastic or metal. Their handle can be bent; the blade can also be movable – giving the possibility of cutting in various planes,
– metal frame saws made of frame tool holders and interchangeable saw blades. These can usually be adjusted (shortened, lengthened) to make them easier to reach,
– fibrin saws for wood, metal, or glass. They have thin saw blades, often reinforced – e.g., with cemented carbides – the teeth enable erasing even complicated shapes. In addition, these saws may have a guide for natural alignment of the blades,
– tilting saws are mainly used for wood, but they are quite universal. They can have different types of modules, including those with large teeth alternately parted – for longitudinal cuts, or with smaller teeth – for transverse cuts. Their variation is the so-called hole saws with a very narrow blade for cutting holes and curves,
Double-sided MacAllister 160 mm
– saw blades, they have a thin edge, allowing for precise trimming of even small parts. The blade is reinforced on the back with flat steel or brass, which significantly stabilizes the work of the saw. The ends have teeth bent forward and cut when we move the saw away and when we bring it closer – the chips are removed,
– cross-cut saws with two handles, operated by two people alternately pulling the blade toward you. They are used for rough cutting large pieces of wood or other quite soft materials,
– angle saws allow precise cutting at various angles. They are equipped with guides, and sometimes also vices and stops built into its base. They are used for trimming, e.g., frames, slats, boards. The adjustable guide has a hoop with an inflated blade and handle. A wide range of cutting angle adjustments is possible, set e.g., every 15 or even 1 degree.
Hand saw teeth should be alternately tilted from the blade plane, one to the right and the other to the left. To correct their deviation, you can use the so-called driller.
Saws are standing new large, and heterogeneous groups. They can be divided depending on:
a) Types of blades used for:
– Circular saws, equipped with rotating toothed blades of circular shape (swords). They can be mounted stationary at a large table, but there are also portable saws, only with a motor and a small table. Circular saws have a number of unique varieties, e.g., miter saw, pendulum saw, shoulder saw, panel saw.
Application: for cutting wood, panels, plastic, or metal, A circular saw cuts materials of different hardness and thickness depending on the drive power and the type of blade. The higher the engine power, the more comfortable and smoother (without slowing down) can be cutting any, even hard materials.
MacAllister frame saw for metal 300 mm
– Frame saws, also known as sawmills, their blades are mounted on the frame, they are mainly used for woodworking, horizontal and vertical cutting of logs.
– Chainsaws, their blade, is a unique chain with U-shaped teeth. They are among the most popular.
Applications: both professional and amateur, they are used for roughing, cutting bushes, cutting branches, firewood – also used in carving.
– Jigsaws are short-saw blades for cutting various profiles, e.g., in wood, metal, or plastic. The right saw blade is attached at one point, works with reciprocating movements.
– Band saws – they have a closed-cut toothed band tensioned on 2 or 3 wheels, of which at least one should be the drive.
Application: for longitudinal, transverse, or profile cuts (uniquely curved, with a radius depending on the width of the tape).
- b) Depending on the type of power supply, we distinguish:
– electric saws, which are driven by a motor powered by current from the socket.
Advantages include smooth operation, the possibility of using it indoors, no exhaust gas. They can have many applications at home, workshop, garden (cutting branches, firewood, DIY). Compared with combustion engines, they are not very loud (around 96-107 dB), but the power of electric motors (from 1700 to 2200) is lower than combustion engines. Electric chainsaws are quite light (from 3.5 to 6 kg), handy.
35 cm OPP electric chainsaw
Disadvantages: necessary access to the socket, possible use of extension cords, quite weak power. Instead, they are suitable for relatively light and amateur backyard work.
– chainsaws – the fuel is gasoline and a unique engine lubrication oil. They are often used in various types of chainsaws. They work well when cutting wood over 30 cm in diameter and many other delicate materials.
Advantages: they have high power (so-called useful power 1.5-9 HP), are reliable and durable, they are characterized by mobility. They are suitable for amateur and entirely professional use; they are not dependent on access to energy; their fuel supply can be easy and smooth.
Disadvantages: they cause a lot of noise ( 109.8-116 dB), emit exhaust fumes. They have a considerable weight from 3 to over 10 kg. The troublesome need to use a mixture of gasoline and oil in the recommended proportions (otherwise engine seizure and permanent damage are possible). They require regular servicing; their operation is not smooth.
– battery saws powered by the included batteries
Advantages: high mobility, no exhaust gases, relatively low noise level (93-94 dB), quick start-up, reasonably smooth operation, especially when using an automatic tool-less tensioning and changing system (chain), smooth, fast operation.
Disadvantages: considerable weight due to the presence of the battery, the need to charge the battery, which can cause a lack of continuity of work, long battery charging time (from 0.5 to 8 hours), and quite short work on them (30 – 50 min).
- c) Depending on the areas of application of saws and saws, we can distinguish:
– professional, high power – they are durable and precise,
– universal – for fairly versatile use,
– for household, hobby, garden or workshop works,
– for tree care, including forestry,
– for rescue (including medical, fire) ).
What to look for when choosing a saw?
When deciding to buy a saw, we should, first of all, take into account the scope, type, and frequency of work and materials that we will most often process.
Engine power is of great importance, affecting the ability to perform complicated tasks by a chainsaw. It is the largest in chainsaws (measured in horsepower, even up to 9-10 hp), the weakest are electric chainsaws (from 1.2 kW and their power is given in kW).
Do you know that…
When comparing the power of individual chainsaws, when it is given in different units, it is worth using a practical converter,
i.e. 1 kW equals 1.4 HP.
The weight of the saw may be necessary – lightweight devices are better for easy homework. These will include hand and tricks. Battery and petrol are much more massive.
Comfort is also essential, noise levels, the presence of exhaust gases, and dust. For example, chainsaws will do the job quickly, but it will be necessary to use headphones to protect them against high noise or to protect the respiratory system against dust and fumes.
To facilitate and improve the conditions of use of saws, it is worth considering buying models with exceptional amenities and functions. For example, additional features of circular saws can be a system for maintaining a constant speed, the possibility of connecting a bag to collect the generated dust, or the use of sight glasses to monitor the cutting lines.
In chainsaws, it can be ensured that the chain can be tensioned without tools, using a unique knob, there can be vibration reduction systems, vibration damping, blocking accidental switching on.