Set screws

A set screw is easily to identify with its headless design and internal drive

Set screws also known as socket screws, is a type of threaded fastener that is used to secure components in place. They have a distinctive headless design, which means they don't have a protruding head like typical screws, and are typically driven with a hex wrench or Allen wrench.They are commonly used in various applications where a precise alignment of components is required. They can also be used to prevent components from rotating or moving in an unwanted way.

They are often used to fix components onto a shaft, such as securing a gear or pulley to prevent it from slipping. The threaded body of the set screw allows it to be tightened against the surface of the shaft or object, creating a strong clamping force. Set screws are available in various sizes, thread pitches, and lengths to accommodate different applications and requirements. They are widely used in machinery, equipment, electronics, and various industrial applications where a flush, no-head fastening solution is needed.

Set screw point types

• Cup point: The most common type, featuring a hollowed-out end that provides a strong grip on the mating surface (DIN 916 / ISO 4029 )
• Flat point: Has a flat end, used where minimal surface damage is desired (DIN 913 / ISO 4026)
• Cone point: Tapered to a sharp point, offering high holding power and precise location (DIN 914 / ISO 4027)
• Dog point: Has an extended cylindrical tip that fits into a mating hole for alignment (DIN 915 / ISO 4028)
• Half dog point: Similar to the dog point but with a shorter tip.
• Knurled point: The knurled surface provides extra grip and holding power in heavy vibration applications. 

Types of internal drives

• Hex socket (Allen drive): Features a hexagonal recess that requires an Allen wrench (hex key) for driving.
• Hexalobular socket (6 lobe): A star-shaped recess with six points that requires a 6 lobe screwdriver or bit.
• Square socket: Features a square recess that requires a square drive screwdriver or bit.
• Slotted socket: A single, straight slot that requires a flathead screwdriver.
• Tamper resistant star socket: Similar to the standard 6 lobe, but with a pin in the center of the recess, requiring a special tamper-resistant 6 lobe driver.
• Hex Socket with Pin (Security Allen): Similar to the standard hex socket but with a pin in the center, requiring a special security Allen wrench.

Common materials and properties

• Carbon Steel: General-purpose, strong and durable; can be heat-treated.
• Alloy steel: High strength and wear resistance; suitable for heavy-duty applications.
• Stainless steel: Excellent corrosion resistance; used in harsh environments.
• Brass: Good electrical conductivity and corrosion resistance.
• Aluminium: Lightweight and corrosion resistant.