Guide To Socket Head Sets & Grub Screw Point Types
Socket Head Set / Grub Screw Point Types - A Quick Guide
A grub screw, or a socket set screw as they are nowadays known, are headless screws that are fully threaded throughout. They feature a hexagonal drive at one end so that they can be fitted using an Allen key or screwdriver with a hexagonal insert bit. The other end of the screw is known as the point and these come in different variations to suit the application.
This quick guide will run through the varieties of grub screw point types and the situations they are most used for.
Plain Cup Point (PCP)
The plain cup point socket set screw is the most common type of point and is suitable for all kinds of general applications. The point end is a concave cup shape that allows for its’ more universal applications across varying surface types.
| PLAIN CUP POINT (PCP) |
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The cup shape to the screw is to ensure it can hold the target components in place via the pressure from the tip as opposed to the traction from the threads.
As they are a versatile option of set screw, they are used for a variety of purposes but can commonly be found to be used in machinery and motor mechanics.
Flat Point
A flat point socket screw has no type of protruding point, thus is completely flat. They provide the least penetration to the target surface so give less holding power. The flat point causes the least damage when fastening so are usually used for softer target materials or sheet materials.
| >FLAT POINT SCREW |
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Cone Point
Cone point set screws have a distinctively sharper point than all other point types. This feature allows the screw to penetrate a completely flat target surface. Whilst they do provide the strongest holding grip, they are typically more likely to leave marks on the surface.
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A cone point screw is often used for kitchen and/or bathroom wall accessories.
Dog Point
Quite easily distinguishable amongst the other grub screw types, the dog point set screw features an extended point with a flat tip. These types of set screws are used to guide the screw into a predrilled location hole.
| DOG POINT GRUB SCREW |
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The use of a dog point grub screw is typically found to be for rotating parts (gears and shafts) within the engineering and automotive industries.
Knurled Cup Point (KCP)
A knurled cup point set screw has a similar shape point as the cup point screw but is serrated, or knurled, at the tip and has a jagged appearance. The knurled ridges allow for a strong bite when making contact with the target surface – namely softer surfaces. This type of set screw ensures a powerful grip so that the screw can secure into place firmly and is resistant to loosening through vibration.
| KNURLED CUP POINT SCREW |
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Much like a plain cup point set screw, the knurled cup point is used for a variety of applications but where additional gripping capabilities are required.