Comparison GRUNTEK Piranha vs Tajima MG-300FB

The total length of the hacksaw blade.

The value of this parameter is directly related to the saw type (see above). The general rule for choosing is as follows: the blade should be twice as long as the thickness of the largest workpiece that is planned to be sawn. This will provide an optimal range of motion to avoid unnecessary fatigue, and the tool, on the other hand, will not be too bulky. However, a long blade tends to spring back, so when working with hardwoods or other difficult-to-cut materials, shorter saws can also be taken. And in models with interchangeable blades (beam and jigsaw, some mini-saws), length data will be required to search for spare blades.

In general, for simple household tasks for sawing wood, a length of 280 – 300 mm is considered optimal. For a private house with a garden, simple construction work, you should pay attention to larger models — up to half a metre. And the largest two-handed saws can have a length of 1000 mm and even more. More detailed recommendations on the optimal blade length for certain tasks can be found in special sources.

Density of teeth in a complete saw blade; measured as the number of teeth per blade length inch (TPI).

The higher the TPI, the smaller each individual tooth, and vice versa. Other things being equal, large teeth allow you to cut easily and quickly, but not very accurately; small — provide an accurate and clean cut, but at the cost of increased effort and time. Accordingly, when choosing a saw for this parameter, one must proceed from the fact that in this case it is more important — speed or accuracy. In addition, the TPI determines suitability for small workpieces: the smallest allowable log thickness is considered to be a three-tooth pitch. For example, in a 9 TPI saw, three teeth will take up 1/3", or approximately 8.5 mm.

It is worth remembering that only tools of the same type and purpose can be compared by the number of teeth per inch. So, for example, in standard saws for wood, the minimum TPI value is 4, and already in passer saws — 9. The most coarse-toothed today are saws for foam concrete — they have about 1.2 – 1.8 teeth per inch; and the “record holders” in terms of density are saws for metal and jigsaws, for which the TPI value of 24 is almost the standard.

The type of additional coating applied to the regular hacksaw blade (if such a coating is provided at all).

- Anti -corrosion. A coating designed to protect the canvas from corrosion. The tool steel from which modern saws are made is not stainless; therefore, if the tool is planned to be constantly used outdoors or in conditions of high humidity, this feature will not hurt.

- To reduce friction. A coating that reduces the friction force of the blade against the material being cut (usually wood, since this feature is mainly characteristic of saws for this material). Such a coating performs several tasks at once: it facilitates the movement of the hacksaw, reducing fatigue, reduces the degree of heating of the blade (and its tendency to deformation) and reduces the likelihood of jamming the tool in the cut.

The main material used in the construction of the saw handle.

First of all, we note that no matter what material the handle is made of, the manufacturer usually tries to make it comfortable and reliable enough to hold — so that the tool lies confidently in the hand, does not slip out and does not lead to excessive fatigue. For this, a special shape of the handle, a relief notch on the surface, etc. can be provided. Therefore, if you take a tool of approximately the same price level, there is practically no fundamental difference between the materials of the handles, and the choice for this indicator depends mainly on the personal preferences and sympathies of the user. However, each material has its own characteristics:

— Plastic. Inexpensive, easy to process and at the same time quite practical material. Plastic is resistant to moisture, has low thermal conductivity (does not “cool” the hands), its strength is relatively low, but for most cases it is quite sufficient. At the same time, such a handle (especially in an inexpensive tool that uses relatively simple grades of plastic) can crack from a strong impact and is easily scratched.

— Plastic / rubber. Plastic handles with rubber grips. Features of plastic are described above. As for rubber, it is provided mainly for the convenience of holding: this material is softer and “tenacious” than plastic, handles with overlays are less likely to slip out of the hands, and they are somewhat more comfor...table to hold. In addition, rubber is not particularly sensitive to scratches — on such a surface they are barely noticeable, or even “tighten” themselves. The combination of plastic and rubber is one of the most popular options today.

— Aluminium. Usually, bow saws for metal are equipped with aluminium handles (see "Type", "Purpose"). This material is highly durable, and weighs a little, but at the same time it is quite expensive, which is why it has not received much distribution. In terms of practical properties, it is completely similar to metal (see below).

— Metal. This category includes all metals except aluminium alloys (see above). This material is very durable and reliable, and it costs less than aluminium — although it weighs more. However, metal (without special coatings) is not very convenient for holding: they are hard and tend to cool hands at low air temperatures. Therefore, most models with such handles are a specific kind of bow saws: tools in which the handle as such is practically absent, and the back of the frame plays its role. However, occasionally there are saws with separately made metal handles.

— Wood. Classic material for handles, not losing its popularity these days; it is notable primarily for its characteristic appearance, and it is quite pleasant to the touch. However, in terms of performance properties, wood does not have any special advantages over plastic, and such a handle can cost much more. Therefore, in modern saws, wooden handles are often provided not so much for practical as for design reasons, and also as a tribute to tradition — based on buyers who prefer "classic" tools.

— Rubber. The handles usually use fairly dense and hard rubber, otherwise reliability would be out of the question. In terms of its properties, this option is similar to the combination of rubber and plastic described above, adjusted for the fact that in this case there is no plastic base. However inside the rubber handle there may be a blade shank, which plays the role of a base; however, the thickness of such a shank is small, therefore, such handles are classified as purely rubber, and not rubber-metal.

— Wood / rubber. Wooden handles with rubber pads. In general, they are similar to solid wood (see above), adjusted for the fact that soft rubber provides a more confident and comfortable hold in the hand, but at the same time covers most of the pattern on the wooden surface.

— Metal/rubber. Combination of metal base with rubber pads. For the first material, see above; for rubber, see Plastic/Rubber; we only note that the rubber coating in this case also plays the role of thermal insulation, providing comfort in cold weather.

— Aluminium / rubber. Combination of aluminium base with rubber overlays; has no fundamental differences from the “metal / rubber” option described above.

— Metal / plastic. Metal handles with plastic overlays — usually quite small, not even completely covering the handle. Plastic provides additional comfort when holding: it usually has a knurling for a secure grip, and in cold weather such grips do not get as cold on the hands as metal.