What Are The Types of Drill Bits Used In Part Manufacturing?
Selecting the right type of drill bit is not an easy job. You must be aware of which bit is right for your project because choosing the wrong tool gives you poor outcomes in the drilling process. Moreover, it can harm materials and your time and money.
Drill bits are of different forms and sizes available in the market. Their types normally depend on the material that you are going to drill. Some common types include; twist, spade, and masonry bits. They are all intended for particular operations and products. Now let’s move to the various types of drill bits and what purpose each type serves. Since, knowing the right one to pick makes a big difference as far as efficiency is concerned. Therefore, it is worth turning the details to find out what drill bits are worth choosing.
What Are Drill Bits?
Twist bits are needed to create contours and are referred to as drill bits. They come in many sizes and shapes depending on the material type to be used. A proper selection of a drill bit is an investment in productivity and accuracy. The wrong bit can be destructive and increase the working time.
Cutters are usually made for specific applications. They are of various types. For instance; twist, spade, and hole saw bits. Each type offers its unique design for specific use and operation. Knowledge of these bits leads to improved performance and durability of the equipment.
What Are The Key Components of a Drill Bits?
Drill bits are made up of several crucial components. These parts work together to validate effective and precise drilling. So, understanding their functions helps in selecting the right drill bit for your project.
1. Shank: The Holding Part
The shank is the part that secures the drill bit in the chuck. It confirms the bit stays in place while drilling. Shanks come in various shapes, such as round and hexagonal, for different drill types.
2. Body: The Cutting Area
The body of a drill bit contains the spiral flutes. These flutes help remove debris and prevent clogs during drilling. The design of the body affects the bit’s cutting efficiency and speed.
3. Tip: The Cutting Edge
The tip is the sharp end that cuts into materials. It is often made from hardened steel or other rigid materials. The design of the tip varies depending on the material being drilled.
4. Flutes: For Debris Removal
Flutes are spiral grooves along the body of the bit. These grooves help clear out the material being drilled. The number and shape of flutes influence the bit’s performance and efficiency.
5. Point: Precision Stage
The point of the drill bit determines its sharpness and cutting precision. The point angle varies depending on the material being drilled. Moreover, it provides the initial contact with the material, enabling clean entry.
Types of Drill Bits: The Commonest Types
Picking the appropriate type of drill bits is vital for the success of your project. Many types of drill bits and their alternatives can be confusing. Each type of drill bit is made with a certain material and purpose in mind. So, knowing the difference allows you to work with fewer conflicts and achieve more desired outcomes.
1. Twist Drill Bits: The All-Purpose Tool
Twist drill bits are the standard types. These are used in large applications. You will come across them in almost every tool kit. These bits have a helical stepped design for drilling through wood, metal, plastic, and even lite masonry. Generally, they are available in many sizes and materials to suit most of the drilling operations.
Why use twist types of drill bits? They are longer-lasting and come with easier availability. When it comes to drilling holes, twist drill bits are used for both making a small hole for screws only as well as larger ones.
2. Spade Types of Drill Bits: Quick and Efficient for Wood
Spade bits are intended mainly for use on wood. However, they can also be used on plastics and thin aluminum. It has a flat structure more specifically being paddle shaped and entails a point at the end. Their design assists in making clean holes in a variety of materials. Spade bits are recommended especially for making large holes in soft wooden materials.
Why use spade bits? They are speedy and economical. When cutting wood, there arises a need to make a bigger hole. So, the use of a spade is more appropriate than twisting bits.
3. Masonry Drill Bits: Built for Hard Materials
For use in concrete, bricks, and stones, masonry bits are suitable for use in drilling. They incorporate the carbide tip typically designed for handling the pressure as well as the hardness of those challenging materials. A common design includes a thicker body to minimize wobbling and a fluted shaft for efficient debris clearance during drilling.
Why use masonry types of drill bits? They are needed for tough jobs where hard surfaces are involved. If you are using a regular twist bit on masonry then this will most probably cause the wear of the twist bit.
4. Brad Point Drill Bits: Perfect for Woodworking
Brad point bits are designed for high accuracy and work best when used on wood. These bits contain a small protruding piece in the middle where it pins the bit in place for drilling. Their design minimizes wandering and yields a clean and accurate hole.
Why use Brad point bits? While using fine wood or on any application where you need precise holes to accommodate screws or dowels, Brad point bits are the best to go.
5. Hole Saw Bits: Making Large Holes
Circular hole saw bits are employed to make large holes. These are ideal for works like placing locks, land rights, or fixing plumbing pipes. A hole saw bit is typically made from a circular saw blade and a mandrel. These bits are used on fabrics because they rotate at high speeds to cut through the material.
Why use hole saw bits? For applications that require a big hole for pipes, electrical boxes, or ventilation, the hole saw bits are fast and simple to use.
6. Forstner Drill Bits: Smooth, Clean Holes in Wood
Forstner bits cut smooth-bottomed holes in wood. They are deep-drilled cylindrical cutting tools. Forstner bits make nice clean holes with little if any tear-out which makes them useful for furniture making, and cabinetry.
Why use Forstner bits? Forstner bits are best to use if you need a hole with a flat bottom in a specific diameter. They are mostly utilized for boring dowel holes. Further, for producing blind holes in wooden material.
7. Countersink Drill Bits: Clean Holes for Screws
Countersink bits give a conical shape around a hole. This shape enables screws to be level with the external surface of the material.
Why use countersink bits? Countersink bits make your screws appear neat and professional. They also help control the risk of material splitting.
8. Step Drill Bits: Optimal for Thin Materials
Step drill bits are used to make multiple different-sized holes. It is possible to drill successively larger holes in delicate materials, for instance, metal or plastic, in cone-like structures. Such bits are ideal for applications such as sinking holes through sheet metal, and plastic piping.
Why use step drill bits? These save time by comprising several hole sizes in one tool. So, they’re ideal for thin, delicate, and tender materials such as metals, plastics, and some types of wood.
9. Core Drill Bits: For Large-Diameter Holes
End-cutting and center-cutting bits aid in making holes of large diameters in hard materials. There are several of these bits that remove a core of material in a hole that appears circular in cross-section. They are commonly applied in activities like drilling on concrete or tiles.
Why use core drill bits? For a larger diameter hole, core drill bits are the preferred tool. They can be used where heavier work is required like in plumbing, electrical work, and even masonry.
Materials Used in Manufacturing Drill Bits
Here’s a list of the materials used in making drill bits:
- High-Speed Steel (HSS)
- Carbide
- Cobalt Steel
- Titanium Nitride (TiN) Coating
- Black Oxide Coating
- Carbide Tipped
- Stainless Steel
- Diamond
- Alloy Steel
- Titanium-Coated Steel
How to Select the Right Drill Bit?
Choosing the right drill bit is crucial for a successful project. Selecting the wrong bit can lead to frustration, wasted time, and damage to materials. Let’s walk through some essential factors to consider when choosing a drill bit.
1. Consider the Material You’re Drilling Into
Before choosing a drill bit, always think about the material you’ll be incorporating. Different materials require different types of drill bits. For example, wood and metal need specific designs and coatings. The right bit of wood will not perform well on concrete.
Tip: Always match the drill bit to the material’s hardness.
2. Select the Right Size and Shape
Drill bits come in various sizes and shapes. The size determines the diameter of the hole, and the shape impacts the cutting action. So, select the right bit diameter for your hole and the shape to match your drilling needs.
Tip: A larger hole requires a bigger drill bit, so check the specifications before starting.
3. Choose Based on the Job Type
Think about the task at hand. Are you drilling into a soft material like wood? Or do you need to drill through tough metal? Different tasks demand specific drill bits. For instance; twist bits for general use and spade bits for larger wood holes.
Tip: Match the task with the bit design for better results.
4. Understand the Bit’s Coating
Drill bits often come with coatings to improve their performance and lifespan. For instance, Titanium Nitride (TiN) coatings reduce friction and extend bit life. Coatings are particularly important when drilling into tougher materials.
Tip: If you plan to drill a lot of holes, choose a coated bit for extra durability.
5. Look for Durability and Quality
Not all drill bits are created equal. Higher-quality bits tend to last longer and provide clean, and more accurate holes. While they may cost more upfront. Despite this, they save you time and money in the long run.
Tip: Invest in good-quality drill bits for frequent use.
6. Consider the Speed and Efficiency
Some drill bits are designed for faster drilling, while others prioritize precision. For larger holes or faster projects, you may need a bit that can handle higher speeds. However, for precise work, slower, more controlled drilling is often required.
Tip: Choose a drill bit that matches the desired speed for your project.
Geometry and Specifications of Drill Bits
Knowledge of the geometry and specifications of drill bits is central to the selection of the right tool for a job. The geometry of a drill bit refers to its shape and angles. These factors affect how well the drill works, its performance, and how long it lasts.
1. Point Angle
The point angle is an angle made at the end of the drill bit. Here, the cutting action is required. As a rule, the point angles vary between 118° and 140° degrees, depending on the material being drilled. It’s recommended that a 118° angle should be used in general-purpose drilling, and a 135° angle is optimal for hard materials.
Soft materials: 118° point angle.
Hard materials: 135° point angle.
2. Helix Angle
The helix angle defines the spiral flutes made with the axial line of the drill. A high helix angle, let it be 30 to 40 degrees can fastly remove chips. A low helix angle of around 10 degrees to 15 degrees is preferable when drilling metals due to the low probability of binding.
Soft materials: High helix angle (30°–40°).
Hard materials: Low helix angle (10°–15°).
3. Shank Type
The shank of a drill bit goes into the chuck of a drill. There are three main types of shanks:
Straight shank: Standard type, used in most drilling applications.
Hex shank: Formerly offers an assured grip so that the users do not accidentally slip on the surface.
SDS shank: Applicable to hammer drills so more torque can be provided and power transmission is improved.
Harden types of shanks are designed to work with specific drill types and specific applications.
4. Flute Design
The flutes are the spiraling located on the drill body that carries debris as drilling continues. The additional flutes, as well as their geometrical parameters, influence the cutting performance of the bit. Two-fluted drill bits are used in general drilling and three or more in harder materials because of their stability and reduced heat generation.
Two-flute: Soft, non-specific use materials.
Three or more flutes: Tougher materials, better stability.
5. Drill Bit Length
Manufacturers prefer large-size bits when the hole is to be penetrated up to a deeper level while small-size bits are stiffer and more effective for making shallow holes. The length of a single cutting bit depends on the hole depth to be made as well as on the type of material to be drilled.
Shorter bits: More rigid and adequate for shallow hole applications.
Longer bits: Can be utilized for larger holes, but may lose its stiffness.
6. Diameter
A drill bit’s diameter defines its capacity to make a hole; the bigger the diameter, the larger the hole. Standard diameters are usually in steps of 1/64 inch or 1 mm; the diameter must be selected accurately enough to obtain the right hole size needed for fasteners or dowels.
Smaller diameters: Precise, smaller holes.
Larger diameters: Applicable where a higher rate of cutting is necessary.
8. Tolerance and Precision
Tolerance is the measure of the allowable variation in diameter of the drill bits. Manufacturers use inserts and dowels, and drill bits with close tolerances, (+/-0.002″) are needed for accurate holes. For general-purpose drilling, standard tolerance is adequate.
Tighter tolerances: Precision tasks.
Standard tolerances: General-purpose tasks.
Summary
Selecting the right drill bit is critical for achieving the best outcomes in any project. By understanding the geometry, specifications, and materials used in drill bits, you can ensure you’re using the correct bit for the job at hand. Whether you’re drilling into wood, metal, or masonry, each drill bit is designed to serve a particular task. The key factors to consider include the material you’re drilling, the type of hole you need, the bit’s coating, and the precision required. By choosing the proper drill bit, you can work efficiently, extend tool life, and ensure your project’s success.
FAQs
Q1. What’s the difference between HSS and cobalt drill bits?
HSS is for general use on soft materials, while cobalt bits are tougher, and designed for hard metals like stainless steel.
Q2. What does the point angle of a drill bit affect?
The point angle affects the drill bit’s cutting efficiency and precision. A 118° angle is for soft materials, while a 135° angle is for harder materials.
Q3. Which type of drill bit is best for concrete?
Masonry drill bits with carbide tips are ideal for drilling into concrete, as they’re designed to handle tough, and abrasive surfaces.
Q4. How do TiN coatings improve drill bit performance?
TiN coatings reduce friction, increase hardness, and extend the life of the bit. Moreover, it improves performance, especially in high-speed and tough material applications.