Drills: how to choose the bits
The guide to choosing drill bits is a specific section of the larger guide to drills previously written by Emmeti Store. This section will focus on drilling machines and will specifically deal with the choice of the most appropriate bits for the type of material to be drilled and the type of drill.
The Trapani guide is designed to answer the frequent questions we receive from our customers about the various uses to which a drill can be used. Given the multitude of tasks that this power tool can perform, the user is increasingly required to have technical knowledge of the materials and accessories he is using.
We therefore recommend that, if you have not already done so, you read the guide to drill drivers to get an idea of the versatility of use of this power tool and then specifically address the section dedicated to drilling.
The drilling
The most common operation in jobs where power tools are used is undoubtedly drilling. In the shop Emmeti Isolanti offers various specific tools for drilling operations: drill drivers, hammer drills, cordless or electric hammer drills, rotary hammers, etc.
The online shop also offers a wide range of drilling accessories, of which we will only deal with a small part here: drilling bits.
Drills have been created to meet the most varied demands and in order for them to be used to their maximum capacity it is necessary to use the appropriate tips. To drill like a professional you need the right balance between the tool and the accessory applied. Choosing the right tool and the specific accessory for the desired job can be a difficult task, if you consider the vast offer on the market. Our goal is to shed light on this sector and guide you in your choice.
Drills have been created to meet the most varied demands and in order for them to be used to their maximum capacity it is necessary to use the appropriate tips. To drill like a professional you need the right balance between the tool and the accessory applied. Choosing the right tool and the specific accessory for the desired job can be a difficult task, if you consider the vast offer on the market. Our goal is to shed light on this sector and guide you in your choice.
Drill Bits: An Overview
In tools, for example, the higher the power, the more effective the tool will be.
The tip to be applied to your drill must be suitable for the material to be drilled and sufficiently robust to be able to withstand the stresses induced by the power tool. Different materials require different tip designs in order to obtain more precise and clean holes without burrs and chips at the edges. This is achieved by studying a correct profile of the tip and the materials with which it is constructed. In general, wood tips are made of chrome-vanadium, metal tips are made of HSS steel (high-speed steel), and masonry tips have cutting edges made of tungsten carbide.
Drill bits have 4 main areas: the shape of the tip of the bit, the cutting edges, the shank and the type of attachment, all of which are related to each other based on the material for which they were designed. We will go into each of these characteristics in separate sections so that the presentation is clear and comprehensive.
The tip to be applied to your drill must be suitable for the material to be drilled and sufficiently robust to be able to withstand the stresses induced by the power tool. Different materials require different tip designs in order to obtain more precise and clean holes without burrs and chips at the edges. This is achieved by studying a correct profile of the tip and the materials with which it is constructed. In general, wood tips are made of chrome-vanadium, metal tips are made of HSS steel (high-speed steel), and masonry tips have cutting edges made of tungsten carbide.
Drill bits have 4 main areas: the shape of the tip of the bit, the cutting edges, the shank and the type of attachment, all of which are related to each other based on the material for which they were designed. We will go into each of these characteristics in separate sections so that the presentation is clear and comprehensive.
Vertex shape
This part of the drill bit allows you to recognize the intended use of the bit itself. If, for example, on the sides of the vertex there are two or more protruding fins compared to the diameter of the bit itself, it will be intended for drilling on masonry. wood drill bits They are equipped with a sharp tip which serves to direct the drilling tip with greater precision in the initial phase of the work. metal tips have very sharp asymmetrical grooves and thanks to the materials with which they are built or coated, they guarantee greater resistance even if overheated by friction and movement. The Tile drill bits, on the other hand, have the shape of a chisel and are made of tungsten carbide, a material capable of drilling ceramics; alternatively, for this type of material you can use wall drill bits.
Sharp
The cutting edges are a component part of the drill bit. These are made of different materials compared to the rest of the bit, precisely because they must perform and withstand a different workload, higher friction temperatures, more intense vibrations. On the market there are tips with two, three or four cutting edges, specific for masonry of different hardness and composition.
The shape of the tips: the stem
All or almost all drill bits have a helical shank design that helps extract the material being worked at the drilling point. This shape helps reduce the friction during rotation to which the drill bit is subjected, preventing it from overheating, deforming and ruining the quality of the work.
As for the shape of the tip, there are different designs of the helix, each of which is suitable for a specific material. For example, classic twist drill bits, three-point drill bits from 3 to 20 mm and flat drill bits are suitable for wood; both have a thorn that serves to direct the tip into the soft material and improve the quality of the hole. Pillar drill bits are instead suitable for bricks, cement and stone; they have tempered tips that guarantee excellent drilling in dense and resistant materials. Four-spiral drill bits are instead suitable for tiles, stone blocks and plaster; the four spirals help a quicker extraction of the residual material, avoiding the increase in temperature inside the hole and the deformation of the tip itself.
As for the shape of the tip, there are different designs of the helix, each of which is suitable for a specific material. For example, classic twist drill bits, three-point drill bits from 3 to 20 mm and flat drill bits are suitable for wood; both have a thorn that serves to direct the tip into the soft material and improve the quality of the hole. Pillar drill bits are instead suitable for bricks, cement and stone; they have tempered tips that guarantee excellent drilling in dense and resistant materials. Four-spiral drill bits are instead suitable for tiles, stone blocks and plaster; the four spirals help a quicker extraction of the residual material, avoiding the increase in temperature inside the hole and the deformation of the tip itself.
The type of attack
Different fields of work require different power tools, which in turn are designed with specific characteristics. As for drilling tools, such as drills, drill drivers, hammer drills and non-hammer drills, these have different types of attachment, each designed to meet the workload that the tool is required to perform.
In construction, the most common attachment is the SDS-PLUS attachment for small diameter bits and the SDS-MAX for larger ones. These two attachment designs ensure a high transmission of the tool's torque. In other sectors, such as woodworking or carpentry, the most common bits are cylindrical bits and conical bits. Bits with an SDS-PLUS and SDS-MAX attachment need a specific chuck to work, in which only bits with this design can be inserted. Conversely, cylindrical or conical bits are installed on a traditional self-tightening or ring nut chuck. Recently, the market has seen the introduction of a new line of bits compatible with the SDS attachment: these are the four-edge bits. In this field, the Japanese company Makita was the trailblazer with the introduction of the Nemesis SDS-PLUS tips that guarantee greater performance and a perfectly circular hole. Among the other types of attachment we find the attachments with hexagonal shank whose fixed seat shape guarantees a high transmission of force; the 1/4" hexagonal attachment is ideal for screwing thanks to the quick replacement without tightening; the large splined attachment is suitable for demolition tools such as heavy duty rotary hammers.
In construction, the most common attachment is the SDS-PLUS attachment for small diameter bits and the SDS-MAX for larger ones. These two attachment designs ensure a high transmission of the tool's torque. In other sectors, such as woodworking or carpentry, the most common bits are cylindrical bits and conical bits. Bits with an SDS-PLUS and SDS-MAX attachment need a specific chuck to work, in which only bits with this design can be inserted. Conversely, cylindrical or conical bits are installed on a traditional self-tightening or ring nut chuck. Recently, the market has seen the introduction of a new line of bits compatible with the SDS attachment: these are the four-edge bits. In this field, the Japanese company Makita was the trailblazer with the introduction of the Nemesis SDS-PLUS tips that guarantee greater performance and a perfectly circular hole. Among the other types of attachment we find the attachments with hexagonal shank whose fixed seat shape guarantees a high transmission of force; the 1/4" hexagonal attachment is ideal for screwing thanks to the quick replacement without tightening; the large splined attachment is suitable for demolition tools such as heavy duty rotary hammers.
Safety first
Drill bits are accessories suitable for a wide range of power tools. Whether they are drills, screwdrivers, hammer drills or demolition hammers, these are demanding and powerful tools that require good ease of use. Along with practical knowledge of their functions is the awareness that these tools can be dangerous if used improperly or incorrectly; even if they are used in the most appropriate way, it is a good idea to equip yourself with safety precautions and rules. When carrying out drilling work, always wear protective glasses and the noise cancelling headphones; these small measures ensure excellent quality of work and safety for sensitive body parts such as eyes and eardrums.
Wear work gloves and choosing tools with a non-slip grip, or with a provision for a side grip, improves the quality of your work and ensures a firm grip on your power tool: the higher the power required, the better the grip.
We recommend you take a look at the demolition hammer guide, which includes a section on deciding whether or not to opt for a side handle.
Lastly, always assume a suitable position, both in relation to the weight of the tool and the final quality of the work; we recommend taking frequent breaks and pauses in the work to rest the parts of the body affected by the high vibrations caused by drilling.
Wear work gloves and choosing tools with a non-slip grip, or with a provision for a side grip, improves the quality of your work and ensures a firm grip on your power tool: the higher the power required, the better the grip.
We recommend you take a look at the demolition hammer guide, which includes a section on deciding whether or not to opt for a side handle.
Lastly, always assume a suitable position, both in relation to the weight of the tool and the final quality of the work; we recommend taking frequent breaks and pauses in the work to rest the parts of the body affected by the high vibrations caused by drilling.
