The purpose of a grub or setscrew is to join two objects together. They were first developed over 100 years ago, to improve safety by removing the need for a head on the screw. This stopped the head of the screw protruding, therefore reducing the potential for an accident, particularly when used on moving parts within machinery.
Grub screws now commonly have a hexagonal recess, enabling them to be tightened using a hex drive or insert bit, which allows for better torque and reduces the likelihood of the tool slipping out of the screw – as may be the case with a screwdriver. The most common type of Grub Screw is the DIN standard 916, and perhaps surprisingly, there’s a security version of it too.
What is a Security Grub Screw?
Security Grub Screws are essentially stainless steel socket setscrews which have been modified by inserting a pin into the hex socket. The pin prevents a standard hex tool, such as an allen key, from being used with the setscrew, as the pin prevents the driver from being placed into the socket. A matching tool or bit with a hole for the pin is required to fasten and remove the tamper-proof fixing.
The standard security grub screw has a common cup point, conforming to DIN 916, but security versions of other points such as dog, flat and cone, can also be supplied.
More information about Tamper Proof Socket Set Screws
There are various other names which refer to the drive of security grub screw, these include Hex Pin, Tamper Pin Hex, Socket Screw with Pin and DIN 916 with Pin. It is a problem with the fastener industry that there are often several different names applied to the same fixing, but if you are unsure about what you are looking for you can always contact us.
We can offer this range of security grub screws in virtually any size that a standard socket setscrew is available in, with some sizes even available off-the-shelf.
We supply tamper proof grub screws as part of our Pin Hex range of security screws, offering an alternative for an application where there is a risk of tampering. Some sizes available from stock, although we can manufacture a security grub screw to match any standard grub screw size.
There is more information on our security grub screws here and don’t forget if you need non-standard sizes or materials, these are available to order including small volume manufacture. Special bits and key wrenches are available when purchasing these screws.
Originally posted 13th October 2016, this article has been refreshed and updated on 26th November 2020