Different Types Of Screw Tips
When it comes to the anatomy of screws, one often very important aspect seemingly doesn't get the attention it deserves. Screw tips, they play a critical role in ensuring that fastening applications are installed securely, efficiently and reliably.
Sitting at the opposite end to the screw head, screw point types come in various designs, each suited to specific materials, tasks and industries.
Choosing the right screw tip type can significantly impact the performance of a screw and simplify the installation process. In this article, we'll cover the most common types of screw tips, exploring their applications and benefits to help you choose the right one for your project.
Contents:
What Are Screw Tips?
Screw tips are the pointed end of a screw, designed to help it penetrate the material being fastened. The shape and design of the screw tip influence how easily the screw can be driven, how secure the final fastening will be and the overall efficiency of the process. A well-designed screw tip in the right material ensures smooth driving, minimises damage to the material and can even reduce the need for pilot holes in certain cases.
Family Types of Screw Tips
To begin with, all screw tip types fall into one of three functional families: self-tapping tips, self-drilling tips and most commonly at Accu, thread forming machine tips. Each category is defined by how the tip interacts with the material, whether it's designed to tap, drill and form its own threads.
There are various different types of screw tip designs, each with unique shapes that suits different materials and applications. This classification helps engineers and installers select the right family of screw tip based on material type, installation efficiency and fastening strength. Understanding these families ensures more precise application and better long-term performance in your fastening tasks.
Self-Tapping Screw Tip Types
When it comes to self-tapping tip types, we’re referring to screw tips specifically engineered to engage with a pilot hole and then cut or form their own internal threads within the material. These tips allow screws to be installed quickly and securely without the need for pre-threaded holes, making them highly versatile for fastening a wide range of materials such as wood, plastic and thin metals.
By creating their own thread path as they are driven, self-tapping tipped screws provide a reliable hold while reducing installation time and effort, critical advantages in both industrial and DIY applications.
Here's a breakdown of the self-tapping screw tip types that you'll encounter.
Type A Point
One of the most widely used screw tips historically, the type A point screw features a conical point that tapers to a fine, sharp tip. The coarse threads provide adequate biting power to help the screw penetrate into a substrate.
Type A point screws are ideal for pilot, punched and nested holes in thin sheet metal (0.015mm to 0.05mm), plywood, softwood and softer plastics. Its sharp, pointed tip helps initiate penetration into these materials with ease, offering a secure and consistent connection.
Type AB Point
A step forward, the type AB point screw tip builds upon the success of the type A with two large differences. While the tapered conical point and sharp tip are still prevalent, the difference lies in the finer pitch threads along with a slightly larger minor diameter. These modifications allow for greater success of biting, increased headroom for torque and also grant finer granularity in adjustability.
Type AB point screws are perfect for pilot, punched and nested holes in slightly thicker sheet metal (0.05mm to 0.5mm), plywood, MDF, composite boards and plastics. The sharp tip and finer-pitched threads make it easier to penetrate into materials, and the thicker shank allows for greater installation torque in harder materials.
Type B Point
The type B point screw tip offers a variation on the AB tip type by offering the same finer pitched threads and larger minor diameter but the change comes with the point of the tip being blunted. This flattening of the tip doesn't necessarily decrease efficiency as you might think. Remember, these tips are still designed for pilot holes.
Rather, this change is more of a safety precaution as type B is primarily a sheet metal screw tip type. As you can imagine, in corrugated sheet metal roofing installation, having lots of sharp exposed tips on the underside is a safety risk, especially if access is needed. Blunting off the end reduces any snagging or poking risks that could arise.
Type B point screws are suitable for the same installation scenarios as type AB, being sheet metal (0.05mm to 0.5mm), plywood, MDF, composite boards and plastics.
Type F / BT Point
The type F screw tip, also known as the BT point, is a thread-cutting screw designed for use in harder metals such as steel, alloy steel, cast iron and die-cast materials. It features a blunt, tapered point equipped with multiple cutting edges and swarf cavities, facilitating efficient thread cutting during installation. This design allows the screw to create its own threads in the material, eliminating the need for pre-tapped holes.
Type F screws are commonly used in applications requiring robust fastening in heavy-gauge sheet metal, aluminium, zinc, lead die castings, cast iron, brass and plastics. Their ability to cut threads in these materials makes them ideal for industries such as automotive, manufacturing, and construction, where secure and reliable fastening is essential.
Type 1 / D Point
The Type 1 or Type D screw tip is a self-tapping thread-cutting design equipped with fine pitch machine threads and a single flute. This configuration allows the screw to cut its own threads into the material as it is driven in, creating a fine standard machine screw thread. Its sharp cutting edge ensures efficient swarf removal during installation, facilitating a clean and secure fastening process.
Type 1 screws are versatile and commonly used for general-purpose applications, particularly in sheet metals, plastics and other harder materials. They are ideal for installing into pre-drilled holes where a standard machine screw thread is required. Their design makes them suitable for various industries, including automotive, electronics and general manufacturing, where precise and reliable fastening is essential.
Self-Drilling Screw Tip Types
Self-drilling screw tips are designed with a drill-like point that allows the screw to bore its own hole in the material as it is driven. Unlike self-tapping screws, which require a pilot hole, self-drilling screws eliminate this step by combining drilling and fastening into one efficient action.
This capability makes self-drilling screws ideal for use in tougher materials such as steel and other metals, where speed and precision are essential. By drilling their own hole and forming threads simultaneously, these screws reduce installation time and provide a strong, secure hold.
Here’s a breakdown of the self-drilling screw tip types you’re likely to encounter.
Type 17 Point
The type 17 screw tip features a self-drilling tip design with a wide flute and cutting edge that enables it to drill its own pilot hole as it is driven into the material. This tip is characterised by its flattened, sharp cutting surface, which reduces splitting and damage in wood during installation.
Type 17 screws are widely used in woodworking applications, particularly for softwoods and plywood. Their self-drilling capability makes them ideal for fast, efficient fastening without the need for pre-drilling pilot holes, making them a preferred choice in fabrication and carpentry where speed and material integrity are critical.
SHOP TYPE 17 POINT SCREWS
Type 23 / T Point
The type 23, also known as type T, is a hybrid screw tip combining the self-drilling capabilities of the type 17 point with the fine thread-cutting features of the type 1 point. It features a sharp cutting edge with a wide flute that drills a pilot hole while simultaneously cutting precise machine threads into the material.
Type T screws are ideal for applications requiring the speed of self-drilling screws and the strong, clean thread engagement of machine screws. They are commonly used in hardwoods, engineered wood products and thin metals, making them popular in woodworking, cabinetry and light metal fabrication where both fast installation and strong holding power are critical.
Type 25 / AT Point
The type 25 screw tip, also known as type AT, combines the self-drilling tip design of the type 17 with the coarser threads of the type B tip mentioned earlier. This blend allows the screw to drill its own pilot hole while providing strong thread engagement with denser materials.
Type AT tip screws are ideal for hardwoods and heavy-duty wood applications where enhanced grip and resistance to splitting are crucial. Their coarse threads deliver superior holding power, making them well suited for structural timber, heavy cabinetry and applications requiring robust fastening.
Type BG Point
The Type BG screw tip features a blunt die point with a single through slot, forming two cutting edges. This design allows the screw to cut its own threads into materials without the need for pre-drilling, facilitating efficient installation.
Type BG screws are commonly used in applications where reduced driving torque is desired, such as in drywall installation. Their design enables them to penetrate materials effectively while minimising the effort required during installation.
Thread Forming Tip Types
Thread forming screw tips are engineered to create internal threads by displacing material rather than cutting it. These screws have blunt or rounded points with shallow thread profiles that push material aside, forming strong, vibration-resistant threads without producing swarf or debris.
This design makes thread forming screws ideal for softer metals, plastics and thin sheet materials where maintaining substrate integrity is important. Their swarf-free fastening process reduces installation torque and damage, providing reliable connections in both industrial and light manufacturing applications.
Here’s an overview of the common thread forming screw tip types you’ll come across.
Type C Point
The type C screw tip is a thread-forming tip design characterised by a blunt, tapered point with either coarse or fine pitch machine screw threads. This configuration allows the screw to form its own threads in the material without cutting, thereby eliminating swarf and reducing installation torque.
Type C screws are ideal for use in heavy sheet metals and die-castings. They are commonly employed in applications where swarf-free thread formation is essential, such as in automotive, appliance and electrical industries. Their design permits replacement with standard screws in the field, offering versatility and ease of maintenance.
Type CA Point
The type CA screw tip is a thread-forming tip design similar to the type C, featuring either coarse or fine pitch machine screw threads. What sets it apart is the inclusion of a sharp, tapered point, which acts as a locating tip to better align and penetrate holes, especially where adjoining sheet metal pieces may be slightly misaligned.
Type CA screws are ideal for fastening heavy sheet metals and die-castings where swarf-free thread formation is critical. The tapered tip improves starting accuracy and reduces the risk of material damage in applications like automotive, appliance and electrical assemblies, offering superior ease of installation compared to the standard type C point.
Type BF Point
The Type BF screw tip is a thread-forming design featuring a blunt, fluted point that enables the screw to form its own mating thread in the material without cutting. This design eliminates the creation of swarf and reduces installation torque, making the fastening process cleaner and more efficient. The flutes assist in displacing material during thread formation, improving thread engagement and holding strength.
Type BF screws are commonly used in applications involving heavy gauge sheet metals and die-cast materials. They are well suited for industries such as automotive, electrical and appliance manufacturing, where swarf-free installation is critical. Their thread-forming capability allows for direct installation without pre-drilling, offering versatility and ease of maintenance in the field.
Drilling Screw Drill Tip Types
Drill point screw tips with integrated drill bits combine the functions of drilling and fastening into a single component, allowing screws to penetrate materials without pre-drilling. Similar to self-drilling tips, these tips typically feature cutting flutes or drill-like points designed to bore through metals or hard substrates while simultaneously forming threads.
These are in a different section, as for some, there is no universally accepted standard name for these tip types, as many manufacturers develop proprietary designs with patented features to optimise performance for specific applications. These exclusive variants often offer improved drilling speed, reduced torque and enhanced thread formation, tailored to particular materials or industries.
Machine Screw Tip Types
Machine screw tips are designed for use in pre-threaded holes or with nuts, featuring sharp, precise threads that engage existing threads rather than cutting or forming new ones.
These screws typically just have a blunt end and rely on matching internal threads for fastening.
Machine screws are widely used in machinery, electronics and precision assemblies where exact thread engagement and controlled torque are critical. Their consistent thread design ensures reliable fastening in metal and plastic engineered components.
There is one specific instance where different machine tips exist and that is on grub screws. Due to their unique nature, we go over set screw tip types in their own dedicated article.
[Read About Grub Screw / Set Screw Tip Types]
Wrapping Up Screw Tip Types
Understanding screw tip types is essential for selecting the right fastener for your project. Each tip design serves a specific function, whether it’s drilling its own hole, cutting threads, forming threads without damage, or simply engaging pre-threaded holes. By matching the screw tip to the material and application, you can make installation quicker, safer, and more reliable.
Key Takeaways:
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Screw tips are carefully engineered to suit different materials and installation needs, impacting the ease and security of fastening.
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Self-tapping tips create threads in pre-drilled holes in soft materials, ideal for wood, plastics and thin metals.
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Self-drilling tips combine drilling and fastening in one step, perfect for tougher and thicker materials.
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Thread forming tips displace material to form threads without cutting, reducing debris and damage in metals and plastics.
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Machine screw tips rely on existing threads, offering precision fastening in machinery and electronics.
Explore More on Screws:
To expand your knowledge on screws and fastening, explore these helpful articles from Accu:
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How to Measure a Screw - Learn how to accurately measure screws to find the perfect fit for your project.
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Different Screw Head Types: An Engineer’s Guide - Understand the various screw head designs and their applications.
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Screw Drive Types: Which Is Best? - Discover the pros and cons of different screw drive types to improve installation efficiency.
FAQs
Q: What’s the difference between self-tapping and self-drilling screws?
A: Self-tapping screws are designed to create their own threads in a pre-drilled hole, eliminating the need for a nut. They are ideal for materials like wood, plastic and thin metals. In contrast, self-drilling screws feature a drill-like tip that allows them to drill their own hole and form threads simultaneously, making them suitable for thicker materials such as steel and other metals.
Q: When should I use a thread-forming screw instead of a thread-cutting screw?
A: Thread-forming screws displace material to create internal threads, resulting in a stronger, vibration-resistant connection without producing swarf. They are best suited for softer materials like plastics and thin metals. Thread-cutting screws, on the other hand, remove material to cut threads, which can be advantageous for harder materials but may produce debris and require more torque.
Q: Can I use a self-drilling screw in wood?
A: While self-drilling screws are primarily designed for metal applications, they can be used in wood if the wood is dense and the screw is appropriately sized. However, for optimal performance and to prevent damage to the wood, it's recommended to use screws specifically designed wood screws.
Q: How do I choose the right screw tip for my project?
A: Selecting the appropriate screw tip depends on the material you're working with and the specific requirements of your project. Consider factors such as material hardness, the need for a pilot hole and whether you require the screw to drill, tap or form its own threads.