What Are Grub Screws / Set Screws? 

A Grub Screw, also known as a Set Screw, is designed and manufactured without a protruding head. The component is usually entirely threaded so it can be fully driven into a pre-tapped hole in order to secure two objects together with maximum thread engagement. Grub Screws serve a variety of functions, with their unique shape allowing them to be driven entirely through a tapped hole.

What Is A Grub Screw Used For?

Typical Applications

A grub screw is commonly used as a locking device, particularly on custom modified Gears, Taper Locking Bushes, Pulleys or Adjusting Rings. The grub screw is tightened perpendicular to a shaft to restrict the movement of a connected component.  

For example, grub screws are used to secure levers to spindle shafts in door handle mechanisms. The spindle is inserted through the door, and the handle or knob is usually fastened to this spindle using a grub screw. The advantage of a rub screw in this application is that it can be driven all the way into a hole, giving a discrete finish.

Accu grub screws are made from high quality materials such as corrosion resistant stainless steel or hardened steel, which is particularly important for securing door handles because the tip of the Cup Point Grub Screw needs to bite into the groove on the spindle in order to maintain the tension and resist loosening. 

Accu also has a range of grub screws with nylon tips which are specifically designed to protect the material that the grub screw is installed into. 

Unusual Applications

Grub screws from Accu were chosen for ‘The Empire Diamond Brogues’ by the House of Borgezie. Chris Shellis included grub screws from Accu in the development plans for these high-end shoes which sell for £10,000. The grub screws are used to fix the diamonds into the soles of the brogues. The grub screws allow for easy upgrading in the future, when the owner wants the diamonds to be transferred onto a new pair of shoes. 

 

Reasons For Using Grub Screws

A common reason for choosing a grub screw over a traditional screw is when there is a requirement for a neat or flush finish. Their compact design is also advantageous for aerodynamic designs and electronic devices such as mobile phones and electronic cigarettes (e-cigs).

Grub Screw Materials 

Accu has a wide range of imperial and metric sized grub screws which are available in A2 and A4 Stainless Steel, Aluminium, Brass, PEEK and a Chemical Blacking finish. 

Grub Screw Tip/ Point Types

Accu grub screws are available in several tip varieties including the common Cup Points, sharp Cone Points, and protective Nylon Tips, all of which are specially designed for specific applications. Components with unique tips such as Brass Tip Set Screws and Vented Set Screws are also available for specialist applications. Accu can offer bespoke grub screws for specific requirements on request, please get in touch with our team to discuss your application needs.