Different Types of Drill Bits: A Comprehensive Guide

Last Updated on October 16, 2023 by Pro Handyman Australia – Editorial Team

Drill bits are essential components that fit into various different types of drills, empowering users to bore holes into multiple materials. Your choice of drill bit should correspond with the material you’re working with and the specific requirements of the hole you intend to create. This guide will enhance your understanding by walking you through the basics of drill bits, elucidating how their types vary and are tailored to complement the different functionalities and applications.

Key Components of Drill Bits

Before diving into the different types, it’s beneficial to grasp the fundamental parts of a drill bit:

Point: The top conical section, comprised of a spur and a cutting lip, crucial for initiating the drilling process.

Spur: Located centrally on the point, it ensures the drill bit stays aligned.

Cutting Lip: This actively cuts into the material, determining the effectiveness of the drill.

Flutes: These spiral channels, running from the cutting lip to the shank, remove debris, ensuring smooth drilling.

Shank: Inserted into the drill’s chuck, it holds the bit in place. The shank’s design can vary based on the drill type and intended application.

Types of Drill Bits Based on Material and Application

Drill bits are crafted for specific purposes. Their structure, coating, and shape are tailored for particular drilling tasks and materials. This article categorizes drill bits into three: by drilling application/material, by effectiveness, and by shank design.

drill-bits-in-yellow-case

When selecting a drill bit, always consider its purpose. While versatile bits exist, using a bit designed for a specific task, such as the types of wood drill bits, ensures precision and efficiency in woodworking projects. For instance, understanding how to drill into stucco requires the use of a bit that’s specifically tailored for that material.

Materials of Drill Bits

High-speed steel: A combination of carbon steel with traces of chromium and vanadium, this is ideal for drilling into wood, plastic, and softer metals.

Cobalt:When comparing cobalt vs titanium drill bits, one finds that cobalt, as a robust alloy, is excellent for drilling tough materials, particularly stainless steel, due to its heat resistance.

Carbide-tipped: With only the tip made of carbide, this drill bit excels at drilling into masonry, tiles, and concrete.

Solid carbide: Entirely made of carbide, it’s an excellent choice for drilling into hard materials.

Tungsten carbide: This blend of tungsten metal and carbon is even more durable than standard carbide, making it ideal for drilling into exceptionally tough materials like masonry.

Coatings for Drill Bits

Black oxide: This coating enhances the retention of lubricants on drill bits while preventing rust formation.

TiN: A coating of titanium nitrate, it reduces wear and tear on drill bits primarily used for metals.

TiAlN: Titanium aluminium nitrate coating bolsters the resistance to abrasion and heat for metal cutting drill bits.

SG: A silicone-based coating, it facilitates the drilling process into dense metals.

In the realm of drill bits, terms like HSS and SDS are often mentioned:

HSS Drill Bits: Derived from high-speed steel, HSS drill bits are versatile, making them suitable for drilling into wood, plastic, and softer metals.

SDS Drill Bits: Specifically designed for SDS drills, these drill bits have a unique shank with double grooves, ensuring enhanced security and improved hammer action. Typically crafted from tungsten carbide, the combination of this drill bit and an SDS drill simplifies the process of drilling into hard materials like concrete, stone, and block.

Match the Material: Choosing the Right Drill Bit

1. Masonry Applications

Mgtgbao 10pc 5MM Masonry Drill Bits

For materials like brick, block, concrete, natural or artificial stone, masonry drill bits are your best choice. They are designed to minimize chipping and cracking and can also help in reducing noise during the drilling process. These bits are typically made from high-speed steel with a tungsten carbide cutting lip. Depending on the material’s hardness, these drill bits can come with two, three, or even four cutting lips; the harder the material, the more cutting lips are required. While most masonry drill bits are compatible with hammer action drills, always confirm before purchasing.

2. Metal Drilling

When it comes to metals, specialized metal drill bits are recommended. Since metals vary in density and hardness, the type of metal you’re drilling into will influence the choice of your drill bit. For instance, high-speed steel (HSS) drill bits are apt for softer metals, whereas cobalt drill bits are ideal for stainless steel. However, when dealing with extremely hard metals, solid carbide or tungsten carbide drill bits are preferable. Additionally, consider the drill bit’s coating: TiN coatings enhance resistance against wear, abrasion, and heat, while SG coatings facilitate drilling into dense metals.

3. Multi-Material Applications

For tasks that involve multiple materials, multi-material drill bits or metal drill bits serve the purpose. These versatile drill bits are typically forged from high-speed steel (HSS) or cobalt and feature a tungsten carbide tip.

4. Tiling Projects

For ceramic tiles, especially those used in high traffic areas, tile drill bits are essential. These bits possess a diamond-shaped point crafted from tungsten carbide, ensuring a chip-free and crack-free drilling experience. They also come with a centering tip to prevent slipping. While masonry drill bits can be employed for tiles, it’s crucial to use them at reduced speeds and without the hammer function.

5. Tile and Glass Drilling

For drilling into class 3 rated tiles and glass, which are typically used in light to moderate traffic areas, tile and glass drill bits are suitable. They come equipped with a tungsten carbide-tipped diamond-shaped point, which can endure the high temperatures produced during drilling.

6. Woodwork Applications

Though many drill bits can penetrate wood, specialized wood drill bits are the most effective. The best wood drill bits are usually made of steel. Various wood drill bits can drill holes of different sizes. For instance, twist bits are excellent for drilling up to 17-20mm, especially in thicker wood. In contrast, flat drill bits can craft larger holes starting from 13mm in thinner wooden surfaces. For carpentry tasks, three-point bits are employed to drill smaller holes.

7. Auger Drill Bits

Auger drill bits are crafted specifically for deep, precise drilling into thick, dry wood. These bits sport a pronounced central point or spur, which enables users to easily pinpoint the drilling location and ensure the hole remains straight. For tasks where a neat finish is essential, auger bits are a top choice.

8. Brad Point Drill Bits

Brad point drill bits offer a distinct edge in precision when working with wood. With a sharp point at the tip, these bits ensure accurate placement. Their wide flutes facilitate faster waste material removal, and the inclusion of rubber stoppers allows users to predetermine the drilling depth.

9. Combination Drill Bits

The term “combination drill bits” pertains to sets containing a diverse range of drill bit types, suitable for multiple materials and applications. These versatile sets cater especially to professionals and DIY enthusiasts who tackle varied projects.

10. Cone Drill Bits

Specialized for plastic pipes and sheet metals (up to 2mm in thickness), cone drill bits are made from high-speed steel (HSS) and are coated with TiN to minimize friction. Their cone-shaped design permits drilling holes of varying diameters without needing to switch the bit.

11. Countersink Drill Bits

Countersink drill bits create conical holes, allowing flat-headed screws to align seamlessly with the surface of the material. While primarily used on wood, certain countersink bits can also work on metals, softening sharp edges in the process. Some versions merge countersink with clearance drill capabilities, enabling users to drill both the pilot hole and countersink simultaneously.

12. Diamond Tile Drill Bits

For tasks involving tiles and other fragile materials, diamond tile drill bits are indispensable. Their carbide cylindrical points reduce the possibility of tile damage while minimizing dust generation. It’s vital to choose the appropriate drill bit depending on the tile type being worked on.

13. Flat Drill Bits

Also known as spade drill bits, flat drill bits cater to those aiming to drill holes of 13mm or more in thin wood pieces. These bits come with a prominent center point for accurate drilling, producing holes with a flat base. They are particularly useful when the screw or bolt head needs to be embedded within the wood, and it’s recommended to utilize this bit before creating the pilot hole.

14. Forstner Drill Bits

Mengshen Forstner Drill Bits

Renowned in woodworking and cabinet making, Forstner drill bits are instrumental in crafting large, flat-bottomed holes, particularly useful when fitting hinges. They are designed to create clean, smooth holes in wood. Some variants have a distinct central point for precision, while others are designed without one.

15. Hinge Drill Bits

Hinge drill bits bear a resemblance to Forstner drill bits in their application: creating holes apt for fitting hinges. Their uniqueness lies in using the hinge itself as a template, ensuring precision. The bit’s head sits within the hinge’s space, facilitating accurate hole placement.

16. HSS (High-Speed Steel) Drill Bits

As the acronym suggests, these drill bits are crafted from high-speed steel. HSS drill bits are versatile, ideal for drilling into wood and plastic. Their special attribute is their resistance to the heat generated when drilling into soft metals at high speeds.

17. Mortice Drill Bits

These bits, often used in woodworking and cabinetry, are designed to create square holes or slots in wood. Such cuts are essential for crafting mortise and tenon joints. Typically, mortice drill bits are utilized with mortising machines or drill presses, as opposed to regular power drills.

18. Plug Cutter Drill Bits

In professional carpentry, plug cutter drill bits come in handy for creating plugs or holes in wood, effectively concealing recessed fasteners. They often complement countersink drill bits, allowing the screw head to be submerged beneath the material’s surface, ensuring a neater finish.

19. Step Drill Bits

Step drill bits are characterized by their conical shape, punctuated by a series of step-like pyramid structures. They cater to sheet materials, offering the flexibility to drill holes of varying diameters without alternating drill bits. Some even come with spiral flutes to enhance waste material removal.

20. Understanding Shank Types

The shank is a drill bit’s portion that is secured within a drill’s chuck. Depending on the kind of chuck on your drill, there’s an appropriate shank type:

Firecore SDS Plus Carbide Drill Bit Set

  • Hex Shank: A hexagonal shape, predominantly found in screw guns or electric screwdrivers with hammering capability.
  • SDS Max Shank: This slotted drive system shank boasts grooves that fit snugly into a drill’s chuck. Predominantly found on hammer drills or some regular drills, it’s designed for heavy-duty applications.
  • SDS Plus Shank: A variation of the slotted drive system, this type is commonly associated with masonry drill bits.
  • Straight Shank: A simple, cylindrical design without any grooves or notches. It’s suitable for drills with either keyed or keyless chucks that can accommodate drill bits ranging from 10-13mm.
  • Threaded Shank: This shank type threads into handheld drills, offering a compact design, perfect for tight spaces. Some threaded shank bits are crafted for grinders rather than traditional power drills.

Drill bits with varying shank types can be purchased individually or in sets. Sets that offer a mix of different shank types are also available for added versatility.

Selecting the Right Drill Bit

Understanding Drill Bit Sets

While it’s feasible to buy drill bits individually based on immediate requirements, investing in a drill bit set is a prudent choice for those wanting an assortment readily available. Drill bit sets come in diverse combinations tailored to various needs, ranging from multi-purpose sets and material-specific sets to those designed for unique applications.

User Experience with Different Types of Drill Bits

When discussing drill bits, understanding the specifications and technicalities is crucial. Still, nothing beats the hands-on experiences of users who’ve tried and tested them in real-world scenarios. Let’s dive into some first-hand accounts:

TOPEX 128-Piece Drill Bit Set

1. TOPEX TX076: Sarah, a professional carpenter, shared her experience with TOPEX TX076. “I’ve used various drill bits over my ten-year career,” she commented, “but the TOPEX TX076 stands out. While working on an intricate wood project, its precision was unparalleled, making my task much smoother.”

DEWALT DWA1181 21-Piece Set Black Oxide Coated HSS Twist Drill Bit Set

2. DEWALT DWA1181: On the other hand, freelance contractor Mike raved about the DEWALT DWA1181 for masonry projects. “When you’re dealing with tough surfaces, you need something robust and durable. The DEWALT DWA1181 delivered stellar performance, cutting through solid stone like butter,” he remarked.

Both reviews highlight the importance of matching the drill bit type to the specific task at hand, ensuring optimum performance and durability.

In-depth Comparisons: Top Drill Bit Models

For those who love to dive into the specifics, we’ve prepared a comparative analysis of some of the market’s leading drill bit models:

Model Power Longevity Price
TOPEX TX076 High 5 years $$$
DEWALT DWA1181 Medium 7 years $$
Bosch CO21B Low 4 years $
QWORK ‎WD1801 Medium 5 years $$

 

Note: Power indicates the bit’s capability to handle tough surfaces, longevity is an estimate of its lifespan with regular use, and the price is represented in relative terms.

From our analysis, while TOPEX TX076 offers superior power, DEWALT DWA1181 gives a balanced performance with impressive longevity, offering more value for its price. Bosch CO21B might be perfect for those on a budget, and QWORK ‎WD1801 strikes a balance between power and price.

Delving into Drill Bit Angles

The angle of a drill bit pertains to the angle formed between its spur and the cutting lip at the tip. Predominantly, there are two main drill bit angles: 118° and 135°. Bits with a 118° angle exhibit aggressive cutting characteristics, making them optimal for softer materials like wood. Conversely, those with a 135° angle are adept at penetrating harder substances, such as masonry.

drill-bits-on-wood

It’s worth noting that metal drill bits offer a broader spectrum of point angles, including 90°, 120°, 135°, 140°, and 145°. The selection should be based on the metal type being drilled and the drill bit’s composition. Typically, the harder the metal, the larger the required point angle, resulting in a flatter tip.

Navigating Drill Bit Sizes

Drill bits are not only diverse in type but also vary in size to cater to different drilling requirements. To assist in selecting the right size, here are some commonly inquired drill bit size applications:

  • Wall Plugs: The required drill bit size aligns with the wall plug’s diameter. For accuracy, starting with a pilot hole using a slightly smaller drill bit is advisable.
  • Red Plugs: The majority of red wall plugs measure 6mm in diameter, necessitating a 6mm drill bit.
  • Grey Wall Plugs: These plugs vary in size from 6-14mm, so the drill bit size should match the chosen plug’s diameter.
  • Brown Plugs: Predominantly 7mm in diameter, brown plugs are best served with a 7mm drill bit.
  • White Wall Plugs: Their diameter ranges between 6-10mm. The drill bit size should align with the selected plug’s diameter.
  • M10 Anchor Bolt: This bolt calls for a 16mm drill bit.
  • M8 Bolt: For this bolt type, a 14mm drill bit is ideal.

Conclusion

In conclusion, having the right drill bit for a specific task ensures efficiency, precision, and longevity of the tool. While the variety may seem overwhelming, understanding the nuances of each type and size will undoubtedly lead to better drilling outcomes. If ever in doubt, consulting with Perth Handyman Services can provide further guidance and expertise.