Follow-up
the efficiency of sharpening teeth with a file:
The width of the edge of the rhombic file should overlap the edge of the tooth, and in order not to injure your fingers, it is better to put a stopper in the form of a rubber tube on the file 
Secure the saw blade in a vice with the teeth facing up along with a block of wood, first aligning their top edges with the top of the shortest tooth. File the protruding points of the teeth flush with the top edge of the block 
If you had to grind off a lot of metal, then to simplify sharpening, make shallow slits in the cavities between the teeth 
First, evenly and smoothly, without changing the angle of the file, sharpen one side of the row of teeth, and then turn the blade over and sharpen reverse side the same way Follow-up
adjustment of teeth on a hand saw:
Place the top of the tooth being set into the groove of the pliers until it stops in the groove of the limiting bracket so that the middle of the height of the tooth coincides with the protrusion of the lower jaws of the pliers. This will bend 2/3 from the top of the tooth (installing the bracket lower can lead to its breakage) 
Bring the handles of the pliers together and bend the tooth until the lower jaws touch the saw blade 
Compare the distance by which the top of the tooth is bent with the feeler gauge of the desired thickness and, if necessary, adjust it with the screw of spring-loaded pliers. After this, spread the remaining teeth 
Special pliers for setting saw teeth. They have 2 adjusting screws: one (with a spring) - for selecting the distance by which each tooth should be bent, and the second - for selecting the height of the part of the tooth bent from the top
Basic designs of a hand saw:
a) a hacksaw with a universal tooth,
b) a saw with an edge,
c) saw for sheet materials,
d) jigsaw,
e) grooving saw,
e) bow saw,
g) two-handed saw,
h) pruning saw 
It is almost impossible to sharpen a saw with hardened teeth with a file. To improve the cutting ability of the teeth, lightly jerk one or two times on both sides of the cutting blade with an abrasive stone (32-50 or F54-F36 grit) in the direction from the end of the saw to the handle 
Using a miter box allows you to saw off even a few millimeters from the edge of the board without any problems. 
Using tsulagi when sawing small parts
When using a power tool is either expensive, impossible due to lack of electricity, or dangerous in high humidity, you have to think about a regular hand saw...
The variety and constant improvement of carpentry power tools - electric saws, electric drills, electric planes - simplifies wood processing and significantly reduces physical stress on the human body. It is enough to connect the tool to the mains or battery and aim it without much effort. the right side in the process of performing work. And only in cases where using a power tool is either expensive, or impossible due to lack of electricity, or dangerous in high humidity, do you have to think about ordinary hand carpentry tools.
A little about the terms. Of the two professions - joiner and carpenter - we will give preference to the first, following the argumentation of Chekhov's Luka Alexandrovich, explaining to his Kashtanka: “You, Kashtanka, are an insect creature and nothing more. You are against a person like a carpenter against a joiner...”
Working with a hand tool, of course, is more difficult than with an electric one, since you need to manage to activate it with muscle effort and at the same time apply professional techniques and skills. However, with a certain skill, the quality of the finished product does not suffer at all. And physical activity when working with hand tools is no less useful than working out in the gym.
One of the most common types of hand tools is a hand saw, which is found in every home and about which, it would seem, everything is known. At the same time, such manufacturing companies as the Swedish SANDVIK, the American STANLEY, the German STABILA and KONEX, the Danish EIHEN, the Finnish PIKOTERA, the Dutch PREMIUM, the Spanish ASCONA and FURKA, the French ULTRA, as well as a number of Russian factories, for example, Izhevsk, Nizhny Novgorod and Novosibirsk continues to improve hand saws and supply them to our market.
A little more about the terms. When talking about the result of working with a saw, three equivalent terms are usually used in the domestic literature - sawing, sawing and sawing. National peculiarity the common root of these words in the presence of any prefix intuitively evokes side associations. Obviously, this is why in the Russian standard for hacksaws the first term was chosen as the most optimistic.
Basic rules for choosing tooth pitch
It is easier to saw if there are at least 8-10 teeth in the cut at the same time.
A saw with large teeth cuts faster, but the edge of the cut is uneven and jagged due to the vibration that occurs when there are not enough teeth working simultaneously.
Tools with fine teeth cut more slowly due to the difficulty of removing sawdust from the cut, but the edge of the cut is cleaner.
When cross-cutting large-fiber wood, it is most convenient to use a saw with a large tooth or with TPI = 7-3.5 (t = 3.5-6.5 mm), for regular sawing - with a medium tooth or with TPI = 9-7 (t =3-3.5 mm), for precision sawing - with a fine tooth or with TPI=13-9 (t=2-3 mm), and finally, for ultra-fine carpentry work - with a very fine tooth or with TPI=16- 13 (t=1.5-2 mm) and even with TPI=19 (t=1.25 mm).
For effective use muscle effort of the carpenter, the saw blade with a large tooth should be long enough - 550-650 mm, the blade with a medium tooth - 450-550 mm long, and with a small tooth - up to 350 mm.
Each saw tooth, in one stroke of the blade, cuts into the material to a portion of its height, gradually forming a cut of the required depth. To cut the fibers of the material, the saw teeth must have sharp blades, which are sharpened with a file, grinding wheel or abrasive stone. If the saw tooth is not hardened, it is easier to process it with a file with a triangular or rhombic cross-section.
The tooth size of a hand saw affects both productivity and ease of sawing and is assessed by tooth pitch, which is measured in some countries differently than in Russia. We denote it with the letter t and measure it in mm as the distance between the tops of adjacent teeth (for example, t = 2.5 mm). In a number of countries it is designated TPI (after the first letters of the English phrase - teeth per inch) and is measured by the number of teeth per inch (for example, TPI = 7 or 7 teeth per inch). This is due to the protracted transition of these countries from the outdated “humanized” system of measures, operating with such units as foot (English foot - leg) and inch (Dutch duim - thumb), to the generally accepted international metric system SI. That is why some imported hand saws indicate the tooth pitch in TPI, which can be converted into pitch t by dividing 25.4 mm by the TPI value, and rounding the resulting quotient to a multiple of 0.5 mm.
To prevent the blade from jamming in the material, after sharpening the teeth, they are set apart, alternately bending one tooth to the left, the second to the right, the third to the left, the fourth to the right, etc. As a result, the set teeth make the cut wider than the thickness of the hacksaw blade.
The distance by which the top of each tooth is bent should be limited - if the distance is not sufficient, setting the teeth apart does practically nothing, and if the distance is too large, sawing becomes more difficult, since other parts of the tooth begin to work together with the blade. As a result, a significant amount of material is converted into sawdust. To determine the optimal amount of tooth spread, you can use the diagram below.
It is not so easy to move the saw teeth quickly and, most importantly, correctly. The carpenter sets the teeth apart with a special key with slots - “setting”, or even “by eye” with a screwdriver with a wide blade or the tip of an ax. Using special pliers and a set of feeler gauges will help to quite accurately set the saw teeth apart if you lack skill.
Depending on the purpose of the saw, its teeth can have either the same or different shapes. The wood is sawed across the grain with a hacksaw with a straight triangular tooth, which cuts both during forward and reverse strokes of the blade with obliquely sharpened blades located on both sides. The wood is sawed along the grain with a hacksaw with flat edges of an inclined triangular tooth, the top of which works like a narrow chisel when the blade moves straight. Such a tooth rather scrapes, rather than cuts, the fibers, but, surprisingly, the cut walls turn out smoother than in the first case. To cut both along and across the grain, the same hacksaw must have a universal tooth, which is slightly inclined forward compared to a straight tooth. Such a tool is less productive, since it cuts when moving only “from itself”, and when moving in the opposite direction, efforts are wasted. The STANLEY company offered its own version of changing straight teeth, making them taller with a sharpening angle of 26 and grinding the tips at an angle of 30. Sharpening the three resulting edges makes it possible to saw equally successfully during forward and reverse strokes, so this tooth was called jet-cut, which corresponds to the definition of a tooth for high-speed sawing.
To increase productivity and improve the quality of cut walls, along with blades with same shape teeth, blades with special combinations of 3-5 teeth of different shapes are increasingly used. Thus, to neutralize vibration and “bouncing” of the blade when sawing thick lumber (beams, logs, sleepers, timber), saws with variable tooth pitch are often used. Cutting fresh and wet wood is more effective with a blade that has four straight triangular teeth alternating with one double wolf tooth, which removes the wood fibers separated by the first four teeth from the cut. SANDVIK produces XT blades, every third tooth of which is shorter than the others and set apart, and the remaining teeth are straight. This blade cuts faster and maintains the straightness of the cut well, increasing efficiency by 20% when cutting crosswise and by 50% when cutting longitudinally.
Craftsmen invent their own versions of saw sharpening. Thus, Sergei Fedorovich Zyubin, whose hobby is making carpentry tools, makes every third saw tooth shorter and straight, and the remaining teeth with a peculiar sharpening, which allows sawing almost without spreading the teeth.
Sometimes, in order to effectively use muscle force, the maximum value of which occurs in the middle of the saw blade, the straight teeth at the ends of the blade are ground to approximately a third of the height compared to the teeth of the central part. This significantly reduces the force required at the beginning and end of each saw stroke.
The steel of the saw blade must be hard, durable and elastic. The first property ensures long-term operation sharp teeth without dulling, the second reduces the possibility of blade breakage, and the third helps maintain the functionality of the tool during sudden changes in force, for example, it eliminates the possibility of blade bending when jammed. If after a special heat treatment bend a blade made of high-quality steel and then sharply release it, it should quickly restore its original shape and at the same time make a slight ringing sound. As a rule, those companies that not only produce tools, but also produce and heat-treat steel for them, such as SANDVIK, manage to ensure an optimal ratio between the hardness and elasticity of the blade.
In many saws, the cutting blade is made even harder due to the fact that not the entire blade is hardened, but only the teeth. This allows you to keep the tool sharp 5 times longer. This type of saw can be distinguished from a regular saw by the blue-black color of its teeth. It is especially effective when sawing reinforced materials such as chipboard, fiberboard, laminated plastics, plaster, and materials with variable thickness thickness - multi-layer plywood, foam concrete, solid fiber. The only caution is the danger of sawing “on nails,” since it is unlikely that it will be possible to subsequently restore the cutting ability of such a saw using conventional methods.
To perform large-scale work with soft materials and with not too stringent requirements for the quality of the cutting edge, for example, for rough sawing of logs, you should choose a saw with a large tooth. A large amount of sawdust can clog the small spaces between teeth and prevent the teeth from penetrating into the material.
For hard materials such as oak, beech, teak, you should use a saw with a medium tooth. For sawing very hard (plastic, aluminum) and wood sheet materials, preference should be given to a tool with a fine tooth, which will prevent the saw from getting stuck in the material and will not lead to uneven movement and jerking of the blade during operation.
Finally, to get a clean cut edge, you should accept a low cutting speed and use a saw with the smallest tooth possible in all of these cases.
Applying a special black polymer coating to the saw blade, firstly, increases its anti-friction properties and provides the saw with easier running, and secondly, ensures the blade's corrosion resistance both when sawing wet materials and when storing the tool. The thickness of this polymer-coated canvas is 1 mm.
Choosing the right saw tooth isn't everything. For different types different designs of hand saws are also used for work. There are eight of them in total: a hacksaw, a back saw, a saw for sheet materials, a circular saw, a mortise saw, a bow saw, a two-handed saw and a pruning saw. Sometimes the listed types also include a jigsaw, which can be considered a kind of “younger brother” of a bow saw.
Most often, for longitudinal and transverse sawing of materials with a fibrous or layered structure, a hacksaw with a universal tooth is used. A saw with an edge is used for processing the edges of boards and for working with a miter box. A mortise saw is similar to a mortise saw, but has a narrower blade and finer teeth so it can cut tenons for joints and lugs. The steel backing gives the canvas greater rigidity, which makes it possible to reduce its thickness to 0.5 mm.
A saw for sheet materials is used, for example, for sawing plywood (it is sometimes called a plywood saw). The rounded front of this tool has additional teeth cut into it to cut into the middle of sheet material. The circular saw is designed for sawing in narrow spaces and along complex curved contours. It is less rigid than a jigsaw, but is often more comfortable to work with.
The bow saw, which is usually 2-4 times as long as it is high, is used for both rough sawing of logs and fine carpentry work. This versatility is explained by the high rigidity of its tensioned blade, which, like a mortise saw and a saw with a back, can have a thickness of up to 0.5 mm.
Probably, the two-handed saw was invented in our country, because when doing work together, both pull in different directions and only “toward themselves.” It is used for rough sawing of logs and preparation of firewood of any thickness. A pruning saw is indispensable for cutting limbs and branches on trees, which is why it is also called a pruning saw. It is produced both in a folding version (like a penknife) and in a version that allows the use of an extension pole.
SANDVIK has made it as easy as possible for the buyer to select a saw with the required tooth pitch. A bright triangle of one of four colors is applied to the surface of the blade of each saw: blue - a tool for large-sized lumber (logs, beams); green - a tool for medium-sized lumber (boards, bars); red - for small lumber (slats, baseboards, shingles) and, finally, yellow - on special-purpose saws (groove, round, for sheet material).
By doing complex work a saw with an edge or a hacksaw with fine and very fine teeth; usually a miter box is used - a special device for guiding the blade when sawing. The traditional design of a miter box is a wooden box with slots in the walls for a saw blade. The slots are located in three directions and resemble the Roman numeral XI. Over time, the width of the miter box slots increases, and jagged edges appear, which impairs the accuracy of sawing and, consequently, the quality of the work.
Recommendations for choosing the tooth pitch of hand saws for sawing various materials
| Material | Tooth pitch in TPI (t in mm) at the following material thickness | |||
|---|---|---|---|---|
| Up to 6 mm | 6-15 mm | 15-30 mm | Over 30 mm | |
| Tree |
|
|
|
|
| Soft | 13-9 (2-3) | 9-7 (3-3,5) | 7 (3,5) | 5 (5) |
| Medium hard | 13 (2) | 9-7 (3-3,5) | 7 (3,5) | 7 (3,5) |
| Solid | 13 (2) | 9 (3) | 9-7 (3-3,5) | 9-7 (3-3,5) |
| Layered | 13 (2) | 13-11(2-2,5) | 9 (3) | 9 (3) |
| Fibreboard |
|
|
|
|
| Insulation material | 9 (3) | 7 (3,5) | 7 (3,5) |
|
| Wall slab | 9 (3) | 9 (3)-7 (35) | 7 (35) |
|
| Solid fiber | 13 (2)-9 (3) | 9 (3) | 7 (35) |
|
| Pressed sheet material |
|
|
|
|
| Soft | 13-9 (2-3) | 9(3)-7 (3,5) | 7 (3,5) |
|
| Medium hard | 13-9 (2-3) | 9 (3)-7 (3,5) | 7 (3,5) |
|
| Solid | 13-9 (2-3) | 9-7 (3-3,5) | 9-7 (3-3,5) |
|
| Laminate | 13-9(2-3) | 13-9(2-3) | 9-7 (3-3,5) |
|
| Single or multi-layer plywood | 13-11 (2-2,5) | 9 (3)-7(3,5) | 9 (3)-7(3,5) |
|
| Foamed concrete | 9(3) | 9-7 (3-3,5) | 9-7 (3-3,5) |
|
| Plaster of Paris | 9 (3) | 9-7 (3-3,5) | 9-7 (3-3,5) |
|
| Sheet plastic |
|
|
|
|
| Soft | 13 (2) | 9 (3) | 9-7 (3-3,5) |
|
| Solid | 13-9 (2-3) | 9-7 (3-3,5) | 9-7 (3-3,5) |
|
| Aluminum | 13 (2) |
|
|
|
Red numbers - blade with hardened teeth
A modern metal miter box is lighter, simpler and, most importantly, more convenient, and it can be installed for sawing with both the right and left hands. In it, the blade is reliably guided by a spring plate that does not interfere with the saw’s free movement. When using such a miter box, the saw blade can be turned in relation to the wood fibers discretely after 15. This device will ensure the correctness and accuracy of the resulting cuts for many years.
For sawing small parts, tsulaga is sometimes used instead of a miter box. It is a rectangular piece of board or multilayer plywood with two bars nailed on opposite sides. The tsulaga is placed on a workbench and rested with the bottom bar against the edge of the table. The part is placed on the upper plane of the tsulagi and pressed against the upper block, which, being shorter than the width of the board, determines the direction of sawing.
Many companies sell saws whose teeth are covered with a specially fitted skid cover so that they do not become dull due to accidental impacts. You can make such a case yourself by cutting a rubber or plastic tube of the appropriate diameter lengthwise. When the saw is not in use long time, you should wipe the hacksaw blade machine oil, put a cover on the teeth and choose a drier place to store the tool.
When purchasing a hand saw, manufacturers usually provide a one-year warranty, but good care the tool lasts much longer.
When marking a future cut, it is necessary to take into account its width so that you can cut along the intended line and at the same time maintain the correct size.
The saw should be moved along the entire length of the blade, straining the hand, shoulder muscles and top part bodies. The wide stroke of the saw makes it easier to remove sawdust from the cut. First, you need to lightly cut the saw into the material, and then continue sawing without strong pressure onto the blade, ensuring cutting with the weight of the tool.
If the saw gets stuck in the cut and bends, the cause may be either a small set of teeth or the structure of the material being cut. In the second case, you can apply a small amount of wax or soap to the hacksaw blade, and also insert a homemade wedge into the cut.
When sawing thin layered materials or wood with a large tooth, it is better to move the blade at a slight angle to the surface (no more than 15-25). At least three to five teeth must be in contact with the material at the same time to prevent the possibility of its individual fragments breaking off.
To prevent the material, especially wood, from splitting at the end of the cut, a wooden block should be placed under its lower plane. This way you will also protect the supporting surface of the workbench.
The report uses terms from GOST 26215-84 “Hacksaws for wood”.
The editors would like to express their gratitude to the regional representative of SANDVIK, Alexey Pavlovich Veselkov, for his assistance in preparing the material.
Let's say we need to adjust a wooden plinth or trim the garden. It would seem that we take a hacksaw and saw. What kind of hacksaw do we use for wood? No, the question is not an idle one at all. To be convinced of this, just go to any construction supermarket or online store that sells tools. Dozens of models are presented to our attention. And their differences are not only in logos and prices.
It seems like a simple tool, but no, if you make the wrong choice, at best, you won’t get the expected pleasure from your work. At worst - as the author of the comment on the forum: “It seemed to me that the saws were sold ready for use, i.e. already sharpened and divorced.” So how to choose a hacksaw for wood? What should you pay attention to: brand, length or price? We will try to answer this question in this article.
Main characteristics
The canvas is of primary importance in this tool. The ease of use of the product and its service life will depend on the grade of steel, the correct hardening procedure and successful sharpening. The choice of a hacksaw for wood is based on four basic characteristics:
- blade length;
- tooth size;
- steel type;
- handle type.
The first criterion is the length of the canvas. It depends on the needs of the buyer, for small bars, boards, etc. A 280 - 300 mm hacksaw is quite sufficient. For construction or summer cottages, a sheet of 450 - 500 mm is more appropriate. There is more. When selecting a model, you must clearly know what size wood you are going to cut. The rule is this: the length of the hacksaw should be twice the length of the largest workpiece for which it is intended. You can do less, but ease of use will be lost. This is due to several reasons:
- This ratio allows all the hacksaw teeth to completely come out of the log during cutting, and this effective removal sawdust (will not clog);
- It’s easier on the hands; with more sweeping movements the hand doesn’t get so tired.
The size of the teeth and their sharpening. The accuracy of the cut and its speed will depend on this characteristic. The pattern is this: a small tooth means a clean and precise cut, but less speed; larger - a rough cut at much higher speed and less fatigue. This characteristic on hacksaws is referred to as “TPI,” which stands for the number of teeth per inch (almost 30 mm). The higher the TPI value, the more “delicate” the cut will be. For example, for working with chipboard and fiberboard, this value should be at least 7 - 9. The cut surface will be smoother without a “ragged” edge.
For garden work, cleanliness of the cut is not so critical, especially for trimming or sawing logs. A more important characteristic for such work is the cutting speed and the effort to be expended. For this we need a hacksaw with a TPI value of 3-6, the distance between the teeth is from 4 to 8 mm.
The classic tooth shape is a triangle. As a rule, such saws are of the sharpened type. Last generation hacksaws with hardened teeth have a trapezoidal shape. They are initially designed with increased strength and wear resistance. When it gets dull, we go buy a new hacksaw or change the blade. No matter how hard you try, you won’t be able to sharpen it: repeating the sharpening angles is extremely difficult, and such steel cannot be filed. Provided that the production technology is followed.
Steel type. The standard metal hardness for a wood hacksaw is 45 HRC. Steel with a hardness of 55 - 60 HRC is used for the teeth. This type of hacksaw combines the flexibility of the blade with high resistance to tooth wear. They are easily recognized by their characteristic appearance- the teeth have a darker shade than the rest of the surface of the blade. These hacksaws are of the non-sharpenable type. If the teeth are not hardened, they can be straightened and sharpened.
Lever. The number of calluses on your hands depends on its ergonomics. There are two handle options: reversible or classic. The first option allows you to change blades, for example, in the Bahco Superior EX-19-XT9-C wood hacksaw model.
How to choose?
First of all, it is necessary to determine what type of tool is needed: carpentry or carpentry. Joiner's cut has a more precise and clean cut and is used primarily for dry wood. Cutting speed for of this type the instrument is not the main characteristic.
When choosing a length, focus on your needs, i.e. what size timber or log are you going to cut? If the tool will not be used often, for example, in a summer cottage, choose one with hardened teeth. The service life of such a saw is long. In addition, properly sharpening and setting teeth is its own science, and mastering it for seasonal work in the garden may not be advisable.
The quality of the canvas can be checked upon purchase. To do this, take a hacksaw and see how smooth the canvas is. Next, bend the canvas until you feel resistance and release. The bending force should be slight, do not break it. After this, look at the evenness of the blade at the bend; if the deviation is more than 2 mm, the steel is not of very high quality.
The teeth of a hacksaw have a dual role:
- cut wood;
- remove sawdust.
The smaller the number of teeth per inch, the faster the cutting speed and the less clogging with sawdust. Hacksaws with up to 7 teeth provide high productivity with little user effort. True, accuracy will suffer from this. But even here it is necessary to look for a middle ground, because The greater the distance between the teeth, the smaller the cutting surface. Accordingly, productivity will decrease. The best option would be the following rule: the minimum thickness of the bar should be greater than the pitch of three teeth. Otherwise it will be torment, not cutting.
Hacksaws can be used with longitudinal and transverse cutting methods. Longitudinal blades can be easily recognized by the angle of the teeth; such saws cut only from themselves. Usually their length does not exceed 50 cm, they have an acute cutting angle - 75 - 800. Most of the models presented in stores can be classified as cross-cut hacksaws. They have sharpening on both sides of the tooth. This allows you to cut both forward and backward.
One of the determining criteria for choosing a hacksaw for wood is price. As with everything else, quality products from leading brands will cost more than Chinese brands. This overpayment, in fact, guarantees the durability and wear resistance of such a tool. And with hardened teeth this is very important, it will depend on shared resource operation of such a tool. It cannot be sharpened. Leading manufacturers exercise more stringent control when choosing steel grades and hardening technology. And as we discussed above, even the shape and pitch of the teeth of such a tool will influence a lot. Starting with convenience and effort expended, ending with the accuracy and evenness of the cut.
Models you should definitely take a closer look at
The models below have earned very good reviews, both according to the results of specialized tests of the tool, and according to the users themselves. For convenience, all models will be in increasing price categories, from budget to professional wood hacksaws.
Wood saw Bison Expert, has a very comfortable plastic handle. The teeth are hardened, triangular in shape with two cutting edges. Suitable for both longitudinal and cross cuts. The length of the blade, as well as the number of teeth per inch, is selected by the user independently; there are different variations of this model. It cuts any type of wood well. This tool is suitable for carpentry work because... controllability and cutting accuracy are excellent. For the garden, you can choose a model with a lower TPI value. Cost from 12 to 15 USD.
Wood saw Gross Piranha also available in several versions. Blades Available in different lengths (from 400 to 550 mm) and different amounts teeth The saw is made of hard steel 52 HRc, teeth, hardened 66 HRc with triangular laser sharpening. It cuts smoothly and cleanly. The Piranha wood hacksaw has a Teflon coating, which significantly improves the glide of the blade and allows you to get clean cut edges. The cost of this tool is 12 - 15 USD.
Stanley General Purpose wood hacksaw. This instrument is produced by a French company, has good quality and not at a high price (about 12 USD). Designed for both longitudinal and cross cutting. Length 500 mm with TPI 8. Hardened teeth. The cut is easy, without additional effort. An excellent purchase for a summer cottage.
Irwin Xpert hacksaw. A very good tool for a reasonable price, from 20 USD. The cut was easy, the cut was even and smooth. When sawing hardwood, the force on your hand does not increase significantly. Good ergonomics of the handle. Length 500 mm, teeth, hardened with proprietary geometry, TPI 8.
Sandvik wood saws(in the past), and now it is a well-known instrument under the Bahco brand. Bahco saws with proprietary XT geometry have practically no equal; this is already a category of professional tools. The Bahco ProfCut PC-19-File-U7 model is noteworthy. This is one of the few saws that can be sharpened. Convenient, 475 mm long hacksaw. Sawing smoothly and easily. Cost from 20 USD
By the way, you can get Bahco quality and save money by purchasing a hacksaw under the “Tescha” brand. This instrument comes to Russia from two countries. If you purchase one marked “made in Sweden”, you will have in your hands a tool from the Bahco factory, with its level of quality.
Bimetal - the cutting part of the blade, which is laser soldered to a base made of spring steel, is a complex alloy of several metals obtained different ways. Bimetal HSS M42 (analogue 10Р2М10К8) and HSS М51 (analog 12Р10М4К10) can be manufactured by mutual simultaneous casting, synchronous pressing or galvanic deposition. In the case of metal band saws, different manufacturers use excellent methods for their manufacture, and the quality of the blade, its strength and service life depend on this.
Description GOST R 53924-2010
GOST R 53924-2010 was prepared by JSC "VNIIINSTRUMENT", introduced by the Technical Committee for Standardization TC 95 "Tool", approved and put into effect by Order Federal agency on technical regulation and metrology dated November 12, 2010 N 399-st. GOST applies to endless band saws for cutting long and shaped steel, castings, sheet material, pipes and other products made of ferrous and non-ferrous metals, as well as non-metallic materials on band saw machines.
GOST R 53924-2010 includes modified basic regulations of the following international standards:
- ISO 4875-1:2006 "Fabrics band saws on metal. Part 1. Vocabulary" (ISO 4875-1:2006 "Metal-cutting band saw blades - Part 1: Vocabulary");
- ISO 4875-2:2006 "Metal-cutting band saw blades - Part 2: Characteristics and dimensions".
The following standards are used in this standard:
GOST 3882-74 Hard sintered alloys. Grades (ISO 513-75 "Hard tool materials for cutting. Designation of main chip removal groups and application groups", MOD).
GOST 5950-2000 Rods, strips and coils of alloy tool steel. General technical conditions.
GOST 19265-73 High-speed steel rods and strips. Technical conditions.
Options for manufacturing tape fabrics:
1 - blades made of tool alloy steel according to GOST 5950;
2 - bimetallic blades (cutting part material - high-speed steel according to GOST 19265);
3 - blades made of tool alloy steel with teeth equipped with a hard alloy in accordance with GOST 3882;
4 - blades for friction cutting (under the influence of heat generated by friction) made of fatigue-resistant steel.
Types of tooth set:
1. Standard wiring: Transverse setting of each tooth alternately to the right and left.
Note - does not apply to blades intended for work on ferrous metals.
Figure - Setting two adjacent teeth through one undone one.
2. Setting two adjacent teeth through one undone: Setting one tooth to the right, one to the left, one without setting.
Figure - Setting two adjacent teeth through one undone
3. Wave-shaped wiring: Transverse setting of groups of teeth with regular changes in the direction of setting to the right and left.
Drawing - Wave-shaped layout
4. Group wiring: Transverse setting of several teeth alternately to the right and left, followed by one, at least, undone.
Figure - Group wiring
The general setting of the teeth of band saws of all designs is at the discretion of the manufacturer.
The spacing of the teeth on the sides of the blade should be equal.
Maximum wiring deviations are ±0.05 mm.
The tolerance for straightness of the side sides of the web in the transverse direction across the entire width of the unset part should be no more than 2 µm/mm.
The main dimensions of the canvas must correspond to those indicated in the table
The length of endless band saws is determined according to the type of machine used.
Marking and designation of tape webs
An example of decoding from the markings applied to the Honsberg BI/M42 S 20x0.9x2362 mm, 10/14TPI tape:
Honsberg- German manufacturer of tape;
BI/M42- material of the cutting part of the teeth is bimetal M42;
S- Spectra tooth profile with rake angle 0°;
20
- blade width in mm;
0.9
- thickness of the canvas in mm;
2362
- length of the “endless” fabric welded into a ring in mm;
10/14
- variable pitch of the teeth, indicates that the first inch of the tape blade will have 10 teeth, the second 14 teeth, which will subsequently alternate along the entire length every 2.54 centimeters (Inch = 2.54 cm);
TPI- an abbreviation for Teeth Per Inch, translated as the number of teeth per inch.
All teeth are identical and spaced at the same distance.
- “small” and “large” teeth alternate every inch and it turns out that for one inch there is one constant tooth pitch, and for the second - another. Band blades with variable tooth pitch are most preferable when cutting metal, as they have a wider operating range compared to a constant pitch, and also reduce vibration and noise of the band blade.
Difference between M42 and M51 tapes.
The cutting edge of the M51 blade is slightly harder than that of the M42 blade, but also more fragile. Due to its fragility, the M51 blade makes sense to use when sawing solid workpieces that are not prone to vibrations; for example, it is perfect for cutting stainless steel round timber, which cannot be cut by the M42 blade. The durability of the M51 blade is usually 10-20% higher than that of saws with an M42 cutting edge material. Another important point is that M51 blades cannot be less than 27 mm wide, and the smallest tooth pitch will be 4/6 TPI (the first inch is 4 teeth, the second inch is 6 teeth). For comparison, for M42 tape blades with a width of 27 mm, the finest tooth pitch can be 14 TPI (14 pieces per inch).
Advantages of sawing on band saws
The technology of sawing on band saw machines is increasingly in demand in modern industries. The main advantages of using tape fabrics include:
- the smallest amount of chips and cutting waste;
- high accuracy manufacturing the ends of parts;
- perfectly smooth cutting surface of the part;
- excellent performance and speed of equipment;
- low noise and no vibration.
By using band saw blades instead of basic cutting methods with discs and knives, we ultimately get the opportunity to save money. Metal is used more efficiently, and the generation of production waste is significantly reduced. In addition, the quality of the products produced significantly exceeds the analogues of disk or hacksaw cutting.
1. Preparation for work - running in the belt:
A very important point, since the resource of the belt web mainly depends on the controlled procedure of its “running in”. A sharpened pencil will break immediately, unlike a sharp but slightly dull one; the same principle applies when preparing the canvas. First, you need to let the blade get used to the machine pulleys by running it idle through the air for about five minutes. Then, at a lower blade rotation speed, approximately 70% of the recommended and 50% of the recommended feed speed, saw through the workpieces for about fifteen minutes, and only after that bring the rotation and feed speed to normal.
2. Web tension:
The degree of tension of the belt web is indicated in the operating instructions for the machine. Professional and industrial models of band saw machines are equipped with built-in strain gauges, with which you can control the degree of tension. It is important not to overtighten the fabric, since overtightening significantly reduces the durability, which leads to the rupture of the tape along the weld seam or the formation of cracks. If the blade is not tensioned enough, there will be a deviation from the perpendicular cutting plane and a tortuous cut.
3. Operation of the canvas:
The main indicator of the correct choice of cutting modes is the absence of strong vibrations during cutting and the type of chips. For optimal cutting, each tooth of the blade must cut chips of a certain thickness. In practice, the feed is selected according to the recommendations of the equipment manufacturers or according to the type of chips that are produced during cutting. In the case of thin or dusty chips, increase the blade feed speed or reduce the cutting speed. Slightly curling chips indicate that the sawing mode has been correctly selected. Chips that are thick or have a blue tint indicate an excessive feed rate or a lower cutting speed than necessary. It is also important not to overheat the cutting material of the blade, which means that intensive watering of the blade with coolant, the cutting zone and the workpiece being cut is required. If vibrations occur, reduce the feed. Monitor the quality of the cut surface; scuffing and cavities may result from incorrect selection of pitch, processing modes, or blade wear.
4. Rest of the canvas:
Rest of the blade allows you to redistribute the fatigue stresses that arise during operation, preserve the properties of the tool material and increase the service life. At intensive work throughout the working day it is better to work with two canvases, one before lunch, the other after. At the end of the working day, be sure to loosen the tension of the canvas, or even better, remove the canvas from the machine, turn it inside out, and hang it on a hook.
5. Approximate resource of tape webs:
The durability of the tape depends on many factors, including:
- type of machine;
- operating modes;
- processed material;
- cross section of the material;
- canvas material;
- preparation of the canvas;
- compliance with operating rules;
- finally, the mood of the worker.
On average, with a correctly selected tooth pitch, the resource of one linear meter of blade is enough to saw 1.5-2.5 m² of solid ferrous metal.
For sawing thin-walled workpieces, such as pipes, sheet metal and the like, band blades with a fine tooth pitch are required, otherwise there is a danger of damaging or breaking the tooth of the bimetallic blade.
Blanks big size must be cut with strip blades with a coarse tooth pitch. The coarse pitch increases productivity and leaves plenty of room for free chip formation.
For sawing soft and tough materials such as aluminum and bronze, a lot of free space is required for the formation of chips; blades with large teeth are also used here, as they prevent chips from accumulating and getting stuck between the teeth.
Selecting the pitch of the band saw teeth
The blades are most widely used for cutting profiles and pipes at mechanical engineering enterprises in procurement and serial production. Depending on the thickness of the workpiece, the pitch of the band saw teeth is calculated. Below are special calculation tables that can help you make the optimal choice of tooth pitch for a particular blade.
| Diameter, mm | Teeth per inch | Diameter, mm | Teeth per inch |
| to 10 | 14 | up to 25 | 10/14 |
| 10 - 30 | 10 | 15 - 40 | 8/12 |
| 30 - 50 | 8 | 25 - 55 | 6/10 |
| 50 - 80 | 6 | 40 - 80 | 5/8 |
| 80 - 120 | 4 | 55 - 120 | 4/6 |
| 120 - 200 | 3 | 80 - 150 | 3/4 |
| 200 - 400 | 2 | 120 - 350 | 2/3 |
| 300 - 700 | 1,25 | 250 - 500 | 1,4/2 |
| > 600 | 0,75 | > 500 | 0,75/1,25 |
Band saw pitch size for profile and pipe cutting
| Wall S, mm | Outer diameter, mm | |||||||||
| 20 | 40 | 60 | 80 | 100 | 120 | 150 | 200 | 300 | 500 | |
| 2 | 14 | 14 | 14 | 14 | 14 | 14 | 10/14 | 10/14 | 8/12 | 6/10 |
| 3 | 14 | 14 | 14 | 10/14 | 10/14 | 10/14 | 8/12 | 8/12 | 6/10 | 5/8 |
| 4 | 10/14 | 10/14 | 10/14 | 8/12 | 8/12 | 8/12 | 6/10 | 6/10 | 5/8 | 4/6 |
| 5 | 10/14 | 8/12 | 8/12 | 8/12 | 6/10 | 6/10 | 5/8 | 5/8 | 4/6 | 4/6 |
| 6 | 8/12 | 8/12 | 6/10 | 6/10 | 5/8 | 5/8 | 5/8 | 5/8 | 4/6 | 3/4 |
| 8 | 8/12 | 6/10 | 6/10 | 6/10 | 5/8 | 5/8 | 5/8 | 5/8 | 4/6 | 3/4 |
| 10 | 6/10 | 5/8 | 5/8 | 5/8 | 5/8 | 4/6 | 4/6 | 3/4 | 3/4 | |
| 12 | 5/8 | 5/8 | 5/8 | 4/6 | 4/6 | 4/6 | 3/4 | 3/4 | 3/4 | |
| 15 | 5/8 | 5/8 | 4/6 | 4/6 | 4/6 | 4/6 | 3/4 | 2/3 | 2/3 | |
| 20 | 4/6 | 4/6 | 4/6 | 3/4 | 3/4 | 2/3 | 2/3 | 2/3 | ||
| 30 | 3/4 | 3/4 | 3/4 | 3/4 | 2/3 | 2/3 | 2/3 | |||
| 50 | 2/3 | 2/3 | 2/3 | 2/3 | ||||||
* when cutting pipes lying next to each other, use values with double the wall thickness.
Sequence of actions when choosing band saws
1. Machine model.
Depends on the machine model:
Band saw loop length. For example, the length, width and thickness of the tape web are respectively 5500 x 34 x 1.1 mm. The nominal size of the saw length, which is indicated in the machine passport (in in this case 5500 mm), may have a tolerance of +/- 50 mm. This is the stroke of the tension pulley.
Width and thickness of the canvas. This is usually a constant value. These dimensions have long been formed from the standard sizes of produced “Birmingham rolled” steel and have the following series: 10x0.9; 13x0.9; 20x0.9; 27x0.9; 34x1.1; 41x1.3; 54x1.6 and so on.
2. Cutting edge type of bimetal band saws.
Currently, band saws with the following types of cutting edge are most widely used:
Selection of band saws depending on the hardness of the teeth:
- hardness of the cutting edge of carbon band saws: 62-64 HRC;
- hardness of the cutting edge of bimetallic band saws M2 (Matrix): 62-64 HRCе;
- hardness of the cutting edge of bimetallic band saws M42: 67-68.5 HRCе;
- hardness of the cutting edge of bimetallic band saws M51: 67.5-69 HRCе.
The price/durability ratio is most preferable for saws with a cutting edge made of M42 high-speed steel.
The average price of one meter of WIKUS 34x1.1 saws from M42 is ~9-11 euros, the average price of one meter of Matrix 2 is ~7-8 euros, the average price of one meter of M51 is 12-14 euros.
The ratio of saw durability when cutting structural carbon steels: M42 - 100%, Matrix 2 ~ 60-70%, M51 ~ 115%.
The use of Matrix 2 band saws is justified when sawing small volumes of workpieces, when cutting non-ferrous metals and profile workpieces.
Band saws M51/M71 are used for cutting difficult-to-cut heat-resistant and stainless steels and alloys, titans, etc.
3. Rake angle of the cutting edge of the teeth.
Band saws are available with teeth with a rake angle of 0°, 6-7°, 9-10°, 14-15°.
The larger the rake angle, the better the cutting ability of the teeth, but the less wear resistance.
Saws with a rake angle of 0° and 6-7° are produced for cutting profile workpieces.
Saws with a rake angle of 10°-15° are used for cutting workpieces with diameters over 120 mm, viscous materials, non-ferrous metals, plastics, etc.
4. Selecting the tooth pitch.
TPI is an English abbreviation for Tooth Per Inch (teeth per inch - the number of teeth at a distance of 25.4 mm). The German abbreviation for TPI is ZpZ.
Constant pitch saws. All saw teeth have the same pitch and shape. Used for cutting solid workpieces, soft materials and non-metals.
Saws with variable pitch. Periodically changing tooth root profile. Provides some reduction in vibration and noise during cutting. Used to expand the range of workpiece sizes.
The pitch of the teeth depends on the width of the workpiece being cut.
The rule usually applied is at least 3 teeth in the body of the workpiece, optimally 10-12 teeth, maximum 22 teeth.
For example, to cut an F100 workpiece, you can select a tooth pitch of 3TPI, 4TPI, 3/4TPI, 4/6TPI.
To facilitate the selection of tooth pitch, tables are used.
| Selecting the pitch of band saws for profiles and pipes | |||||||
| Diameter | |||||||
| Wall thickness | <40 | 80 | 100 | 150 | 200 | 300 | 500 |
| 3 | 8/12 | 8/12 | 8/12 | 8/12 | 6/10 | 6/10 | 6/10 |
| 8 | 8/12 | 6/10 | 6/10 | 5/8 | 4/6 | 4/6 | 3/4 |
| 12 | 6/10 | 5/8 | 5/8 | 4/6 | 4/6 | 4/6 | 3/4 |
| 15 | 5/8 | 4/6 | 4/6 | 4/6 | 3/4 | 3/4 | 2/3 |
| 20 | 4/6 | 4/6 | 3/4 | 3/4 | 3/4 | 2/3 | |
| 30 | ¾ | 3/4 | 3/4 | 2/3 | 2/3 | 2/3 | |
| 50 | 3/4 | 2/3 | 2/3 | 1,33/2 | |||
| 100 | 2/3 | 1,33/2 | 0,75/1,25 | ||||
| 120 | 1,33/2 | 0,75/1,25 | 0,75/1,25 | ||||
If necessary, we will help you decide on the choice of band saws for a specific task.
A hand saw, at first glance, is a fairly simple tool that does not require much maintenance. However, few people know about the criteria for choosing a saw and its types. Like other tools, a hand saw has certain signs of quality and characteristics.
Basic parameters of hand tools for cutting wood
A hacksaw is one of the most necessary tools in every man's inventory. This device allows you to easily change the dimensions of wood and plastic lumber. Using a hacksaw, you can perform a lot of operations in construction, cut branches in the garden, shorten fence poles, and so on.
A hand saw is used to work with lumber
But when purchasing such a seemingly simple tool, not everyone thinks about how to make the right choice and what criteria need to be taken into account. A hacksaw has its own special parameters that can affect the quality of work. There are four basic parameters when choosing a hacksaw: blade length, tooth size, steel type and handle type.
Blade length
For ease of use, the length of the hacksaw blade is chosen so that it is twice the size of the material at the cut site. This allows you to effectively remove sawdust during work due to the fact that all the teeth of the blade will come out of the board/log. In addition, this ratio of the size of the hacksaw and lumber contributes to a greater range of hand movement. This, in turn, takes much less effort. In construction, a universal hacksaw with a blade length of 45–50 centimeters is most often used. To work with small bars and boards, a blade 30–35 centimeters long will be sufficient.
Tooth size
This is perhaps the most important parameter. After all, the speed and accuracy of cutting depends on the size of the tooth.. The number of teeth per inch of blade is usually denoted by the TPI coefficient. To work more accurately with the material, it is necessary to use a hacksaw with a high TPI coefficient, that is, with a large number of teeth. When choosing a blade with a TPI of at least 7–9, and a distance between teeth of no more than 2–4 mm, the surface at the cutting site will be smoother and without torn edges. For working with large beams and garden trees, a blade with a TPI of 3–6 and a tooth spacing of over 4 mm will work well. Using such a hacksaw will reduce the effort required and increase the speed of cutting the working material.
Tooth pitch correspondence table
| 1 TPI = 25.5mm | 10 TPI = 2.5mm |
| 2 TPI = 12mm | 11 TPI = 2.3mm |
| 3 TPI = 8.5mm | 12 TPI = 2mm |
| 4 TPI = 6.5mm | 13 TPI = 2mm |
| 5 TPI = 5mm | 14 TPI = 1.8mm |
| 6 TPI = 4mm | 17 TPI = 1.5mm |
| 7 TPI = 3.5mm | 19 TPI = 1.3mm |
| 8 TPI = 3mm | 22 TPI = 1.1mm |
| 9 TPI = 2.8mm | 25 TPI = 1mm |
Sharpening teeth
The usual triangular shape of hacksaw teeth is taken as standard. The teeth are made in the form of an acute triangle or isosceles, depending on the purpose of the cut. Such a blade can be sharpened with particular ease by repeating all the angles of the teeth. This blade can be used for both longitudinal and transverse cuts to avoid rough notches.
The teeth of a classic hacksaw are made in the shape of a triangle and can be sharpened
Video: self-sharpening hacksaw teeth for wood
But modern hacksaws, unlike classic ones, have hardened teeth with a non-standard trapezoidal shape. Such saws are endowed with increased strength and are resistant to wear. Their steel cannot be sharpened, and it is very difficult to maintain all the angles of the sharpened teeth.
Modern hacksaws are made with hardened teeth in the shape of a trapezoid.
Steel type
High-grade stainless steel is most often used to produce hacksaw blades. Typically, wood saws are made of steel with a hardness of HRC45. Very often, manufacturers combine steel in the canvas. In a hacksaw with a combined blade, the majority is also made of 45 steel, but the cutting part is made of 55 and 60 steel. When the cutting edge is hardened, wear resistance increases. This type of tool can be easily distinguished from a regular hacksaw by its dark, hardened teeth.
The first forged saws were made in Ancient Greece. Forging gave high hardness to the metal and improved the quality of the tool.
Handle type
The ease of use of the saw depends on the correct choice of saw handle. Handles are made of wood or plastic. A very important point - the surface at the grip site should be such that the hand does not slip. This can be eliminated by scarring the handle or covering it with a rubber layer. The hacksaw can be either a classic cast saw or with a reversible blade. The latter allows you to replace the canvas, which is very convenient.
How to choose a hand saw
By combining all the basic parameters of the saw, everyone can easily decide for themselves which one suits them best. When choosing a tool, you need to decide for yourself which saw is more suitable - a carpenter's or a carpenter's saw. If the most important thing is cutting speed, then, of course, you need to purchase a carpenter's tool. A carpenter's hacksaw has fewer teeth per inch, which allows for faster cutting performance and sawdust removal. If cutting accuracy is a priority, then you should use a carpentry shop.
The quality of a hacksaw can be determined in simple ways. First you need to visually verify the evenness of the canvas. Then you need to bend the canvas with a little effort and release it as soon as resistance appears. After the blade plays back and calms down, you should again check the evenness of the blade. If it is slightly deviated from the original position, then the tool is of poor quality and it is not recommended to buy it.
If you need a rip saw, you need to choose a hacksaw with sharp teeth. The teeth of such saws are sharpened only on one side, so the cut will be made only in one direction - away from you.
The teeth of the rip saw blade are sharpened in the shape of an acute triangle
When longitudinal sawing, the cut occurs parallel to the fibers of the material. For rip sawing, circular saws and bow saws are well suited.
Crosscut saws are the most common. Their teeth are made in the shape of an isosceles triangle and sharpened on both sides. This allows you to cut in both directions.
For cross cutting, the teeth of the blade are made in the shape of an isosceles triangle and sharpened on both sides
When cross-cutting, the material is cut across the grain. For such sawing, classic hacksaws, hacksaws with a backrest, and, for large material thicknesses, two-handed saws are suitable.
The price of the saw is also an equally important factor when choosing. A more expensive hacksaw guarantees reliability and wear resistance. Those saws whose price is significantly lower than average are made from cheaper raw materials and do not guarantee you long-term service.
What types of hand saws are used for what purposes?
- The classic hacksaw is the most common of all. It has a long and wide canvas. If the blade is too long, the hacksaw may tilt to the side when cutting. Great care must be taken to avoid deviation of the cutting line from the initial marking. This hacksaw is suitable for working with timber, boards, chipboard and so on.
- Hacksaw with back. This saw model has a rigid rib attachment, which minimizes the vibration frequency of the blade. This hacksaw also has smaller teeth and a higher TPI coefficient. They are designed for cutting plywood, chipboard with a coating layer and sawing profile strips.
- Finish saws have an adjustable handle. They are needed for cutting grooves, grooves and straight and profile planks.
- A circular hacksaw, or a hacksaw with a narrow blade. It is also used for cutting grooves, as well as for cutting out parts with rounded areas and large holes.
- A bow saw is well suited for cutting knots and rough parts of material, as well as for cutting out parts from plywood and wood. This hacksaw is distinguished by a thin blade fixed on both sides in a frame. It is worth noting that you need to work with it extremely carefully due to its increased fragility.
- The award has two handles. The appearance of such a saw is in many ways similar to a plane. It is used for cutting tenons and grooves, deepening holes and slots in materials of any hardness.
- Garden saw with curved blade. Most often, for greater convenience, they are made folding. This saw is well suited for garden work. The saw blade is made of chrome steel. Widely spaced teeth with an inclination in the direction of the handle will allow you to conveniently cut down twigs and branches, placing emphasis on yourself while cutting.
- A two-handed saw has the highest productivity. It has two wooden handles. For greater efficiency, cutting with such a saw requires two people. A two-handed saw is often used for sawing large logs and trees.
- A hand or pocket chain saw is a small piece of chain with two handles at the ends. This saw is convenient for both one and two people to work with. The log or branch is wrapped around a chain and cut is made using the handles. A manual chainsaw, like a folding one, is well suited for gardening.
Photo gallery: types of hand saws
This classic hacksaw can be easily sharpened. This hacksaw has hardened teeth and increased wear resistance. A hacksaw with a back or butt minimizes vibrations of the blade during work. A hacksaw with a narrow blade is well suited for cutting holes and grooves. 
This type of saw has an adjustable handle, which allows you to work at the desired angle. A bow saw is well suited for cutting parts from plywood. This type of hacksaw is similar to a plane and is used for cutting tenons and slots. A two-handed saw is suitable for cutting large logs. 
Garden saws with curved blades are well suited for cutting down knots and small tree branches. 
The hand chain saw is compact and well suited for sawing logs while camping and branches in the garden.
Thus, having carefully studied all the nuances regarding hand saws, everyone will be able to choose the most suitable option for themselves. Choosing the right tool will provide you with high-quality and enjoyable work.
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