Carbide-tipped circular saw blades are high-efficiency cutting tools. They are widely used in cutting wood, plastic, aluminum profiles, acrylic, and furniture industries due to their narrow cutting kerf, high efficiency, and excellent cutting surface quality. By introducing the names of each part of the carbide-tipped circular saw blade, this article helps to understand the composition structure of the saw blade and the selection of saw blade parameters in CAD software design.

Introduction to Components of Carbide-Tipped Circular Saw Blades

A carbide-tipped circular saw blade consists of a carbide saw blade tip and a blade body. The blade body is a steel plate, mostly made of high-quality steel plates such as alloy tool steel and spring steel.

1.1 Functional Structures on the Blade Body

During operation, the saw blade rotates at a high cutting speed, generating a large amount of heat. To achieve better heat dissipation, several heat dissipation slots or holes can be designed on the blade body.

Due to the high rotational speed during operation, the saw blade produces significant noise. Different silencer slots can be designed according to the material being cut to minimize noise pollution as much as possible.

Mounting holes can be designed based on the spindle diameter and installation method of the machine tool, including plain holes, keyway holes, and holes with small round holes.

1.2 Saw Blade Tip and Welding Process

The saw blade tip is made of cemented carbide and needs to be welded to the blade body via silver brazing, which can be done manually or by automatic welding machines. The structure of the carbide-tipped circular saw blade is shown in Figure 1.

Figure 1 Structure of Carbide-Tipped Circular Saw Blade

Selection of Carbide Saw Blade Tips

Cemented carbide is an alloy material made from hard compounds of refractory metals and binder metals through powder metallurgy technology. It is widely used as a tool material due to its high hardness and wear resistance.

Types of Cemented Carbide for Saw Blade Tips

There are two main types of cemented carbide: tungsten-cobalt (YG) and tungsten-titanium (YT). Tungsten-cobalt cemented carbide has good impact resistance and is widely used in wood processing.

Grade Selection of Saw Blade Tips

Common grades include YG8 to YG15, where the number after YG represents the percentage of cobalt content. The impact toughness and bending strength of the alloy increase with the increase of cobalt content, while its hardness and wear resistance decrease accordingly.

Therefore, the grade of the saw blade tip material should be selected according to the material to be cut. For example, a higher grade can be chosen for ripping softwood, while a lower grade is preferred for cross-cutting solid wood that requires high hardness of the saw blade tip.

Selection of Blade Body Parameters

Selection of Blade Body Material

65Mn spring steel is widely used as the blade body material by domestic saw blade manufacturers due to its good elasticity, ductility, excellent hardenability during heat treatment, and cost-effectiveness. However, due to its low heat resistance temperature and tendency to deform when heated, it is only suitable for saw blades with low cutting requirements.

50Mn2V alloy steel has improved hardenability by adding 0.08%–0.16% vanadium. Meanwhile, increasing the manganese content and reducing the carbon content enhances various mechanical properties of the steel and improves its heat resistance, with the heat deformation temperature reaching 300–400℃, thus extending the service life of the saw blade. This material is suitable for manufacturing high-grade carbide-tipped circular saw blades.

Common grades of blade body materials used in China include 45Mn2V and 50Mn2V, while the grade used in Japanese saw blade bodies is SKS5.

Selection of Blade Body Thickness

The thickness of the blade body determines the width of the saw blade tip, and the width of the saw blade tip is generally about 1 mm larger than the thickness of the blade body.

Although a thicker blade body offers higher strength, it will also increase the width of the saw blade tip, leading to a wider cutting kerf and greater material consumption. The thickness of the carbide saw blade is determined by the material of the blade body and the manufacturing process. An excessively thin blade body tends to vibrate during operation, affecting cutting quality.

The selection of blade body thickness should consider both operational stability and material saving. Note that some saw blades have a fixed thickness, such as grooving saw blades and scoring saw blades.

Selection of Blade Body Diameter

The diameter of the saw blade is related to the thickness of the workpiece to be cut and the equipment used. For a given blade thickness, a smaller diameter means higher strength.

According to the thickness of the processed material, common saw blade diameters are: 110, 150, 180, 200, 205, 250, 255, 300, 305, 350, 355, 400, 500 (unit: mm). The diameter of the bottom slot saw for precision panel saws is mostly 120 mm. The empirical reference for the corresponding relationship between the designed blade body thickness and diameter is shown in Table 1.

Table 1 Correlation Between Design Thickness and Diameter of Saw Blade Body

Determination of Tooth Number

The number of teeth of the saw blade is determined by the material to be cut and the cutting method, with a typical tooth pitch ranging from 15 to 25 mm. For example, more teeth should be designed when cutting dense and hard materials; on the contrary, fewer teeth are needed for loose materials to allow larger chip pockets.

When cutting the same type of wood, the number of teeth varies between ripping and cross-cutting. Ripping involves cutting along the wood grain, so fewer teeth are required; cross-cutting involves cutting across the wood grain, which has more fibers, so more teeth are needed.

Of course, more teeth mean more carbide saw blade tips are required, increasing the cost of the saw blade. Therefore, multiple factors need to be considered when determining the number of teeth.

Selection of Saw Blade Tooth Profile

Common types of saw blade tooth profiles are shown in Figure 2.

Flat teeth: Simple to grind and low in cost, mainly used for cutting ordinary wood or as grooving saw blades to ensure a flat groove bottom.

Alternate top bevel (ATB) teeth: The most widely used, featuring fast cutting speed and simple regrinding, suitable for multi-blade saws, solid wood ripping, trimming saws, laminate flooring, and aluminum alloy veneers.

Alternate top bevel and flat (ATB + Flat) teeth: Mostly used for grooving veneered plywood, photo frames, and particleboards.

Triple-chip grind (TCG) teeth: More complex to grind, but they can reduce edge chipping of veneered materials and prevent aluminum adhesion and saw marks, making them suitable for panel saws and aluminum alloy cutting.

Electronic panel saws usually have a large diameter (350–450 mm) and thickness (4.0–4.8 mm), and most of them adopt TCG teeth.

Figure 2 Common Types of Saw Blade Tooth Profiles

Design of Saw Blade Cutting Edge Angles

There are six cutting edge angles of the saw blade: radial rake angle, radial clearance angle, tangential rake angle, end cutting angle, side clearance angle, and side radial angle. Among them, the radial rake angle and radial clearance angle have the most significant impact on cutting performance.

Radial rake angle: A larger angle results in better sharpness and faster cutting speed (generally 10°–20°). Select a larger angle for soft materials or solid wood ripping; a smaller angle for hard materials.

Radial clearance angle: Prevents friction between the saw blade tip and the machined surface (generally 10°–15°). A larger angle reduces friction but thins the saw blade tip, lowering its strength.

All angles are shown in Figure 3.

Figure 3 Schematic Diagram of Saw Blade Cutting Edge Angles

Design of Heat Dissipation Slots

Heat dissipation slots are designed to quickly dissipate heat from the saw blade during processing. Without timely heat dissipation, the saw blade will deform, affecting cutting quality and even causing production interruptions in severe cases.

Heat dissipation slots are composed of smooth curves, cut directly by laser, with small round or elliptical holes (about 0.5 mm in diameter) at both ends. Common shapes of heat dissipation slots are shown in Figure 4.

The number of heat dissipation slots is generally determined by the size of the saw blade and the number of saw blade tips:

Saw blades with a diameter of 300 mm or more: Use 3–5 heat dissipation slots (multiple of the number of saw blade tips).

Multi-blade saws or thin saw blades: Use heat dissipation holes instead of slots.

Figure 4 Common Shapes of Heat Dissipation Slots

Design of Silencer Slots

Saw blades generate noise pollution when rotating at high speed for cutting. Noise above 90 dB can affect human hearing, so silencer slot structures should be adopted in saw blade design to reduce noise.

Three types of silencer slot structures are shown in Figure 5:

Type B: Used for multi-blade saws.

Type A: Used for saw blades with a diameter larger than 250 mm.

Type C (with copper rods): Better noise reduction, used for large-diameter saw blades.

The length M of the silencer slot is determined by the diameter of the saw blade (shorter for small diameters, longer for large diameters). Specific dimensions are shown in Table 2.

Figure 5 Three Types of Silencer Slot Structures

Table 2 Corresponding Silencer Slot Lengths for Different Saw Blade Outer Diameters (mm)

Types and Sizes of Mounting Holes

The central hole of the saw blade is the mounting hole, and its diameter is directly related to the spindle diameter of the woodworking saw machine. Therefore, it is necessary to confirm the mounting hole size with the customer during design.

Common types of mounting holes:

Plain holes

Mounting holes with rectangular keyways (one or two keyways)

Mounting holes with small round holes (one or two round holes)

Standard mounting hole sizes in China:

Saw blades ≤120 mm: 20 mm

Saw blades 120–230 mm: 25.4 mm

Saw blades ≥250 mm: 30 mm

Some imported equipment uses a 15.875 mm mounting hole. Mounting holes of multi-blade saws are generally equipped with keyways to ensure operational stability.

CAD Drawing Method for Saw Blades

Basic Steps of CAD Design

The design process of carbide-tipped woodworking circular saw blades involves CAD drawing based on the parameters mentioned above:

Draw horizontal and vertical centerlines, then draw the circle of the saw blade tip and the mounting hole circle according to the designed diameter.

Select the appropriate saw blade tip, determine the radial rake angle and radial clearance angle, and draw the outline of the saw blade tip and tooth seat.

Drawing Tooth Slots and Tooth Backs

The protrusion length of the saw blade tip beyond the blade body is approximately 1.5 mm (offset inward by 1.5 mm using the offset command).

Use the circular array command to create all tooth seats according to the number of saw blade tips.

Draw the tooth slot circle: Measure the tooth pitch a, check the corresponding tooth slot depth h in Table 3, and offset the blade body diameter circle by h.

Form the tooth back inclined line by rotating the tooth seat line by ~15°, then create the tooth slot arc tangent to the tooth seat line, tooth slot circle, and tooth back line.

Figure 6 Diagram of Tooth Seat and Tooth SlotTable 3 Corresponding Dimensions of Tooth Pitch and Tooth Slot Depth of Blade Body

Finalizing the Design

Delete redundant lines, retain one complete tooth profile outline, and use the circular array command to complete all teeth. Then draw silencer slots and heat dissipation slots, and fill in the title block. Figure 7 shows the structural names of the saw blade.

Figure 7 Structural Names of Carbide-Tipped Woodworking Circular Saw Blade Design

The design of carbide-tipped woodworking circular saw blades using CAD software should first determine the required size, tooth profile, and mounting hole size of the saw blade based on the cutting environment and material, then refine each saw blade parameter through adjustment and optimization to design a qualified saw blade that meets the cutting requirements.

Conclusão

The design and selection of carbide-tipped circular saw blades is a systematic project that requires comprehensive optimization of the saw blade tip material, blade body parameters, tooth profile angles, heat dissipation, and silencer structures based on the cutting material, equipment conditions, and production requirements.

With the transformation of the manufacturing industry towards precision, high efficiency, and environmental protection, circular saw blades are also developing in the direction of “higher hardness, lower wear, lower noise, and customization”.

In the future, through the research and development of new materials, optimization of parameter models, and upgrading of CAD design technology, circular saw blades will play a more important role in more complex cutting scenarios, providing stronger tool support for the production upgrading of various industries.

For practitioners, mastering the core design logic and practical methods of circular saw blades is the key to improving production efficiency, reducing costs, and better adapting to the new demands of industry development.