Today workmen adopt tools and techniques that would reduce their workload and hence we have number of tools emerging in the market. Self-drilling screws are one such thing that have replaced the conventional screws. These crews have chisel tip which is similar to that of a drill tip. Thus, it avoids the need of drilling the hole first. Instead, you can use this tip to attach sheets together. The drill bit at the end of these screws, when driven creates holes technically.
So, all self-drilling screws are self-tapping screws except for the drill bit at the end. People often confuse, the self-drill screws with the self-tapping screws but they are different, a self-tapping screw creates a thread but needs a pilot hole.
Types of Self-Drilling Fasteners:
There are different types of self-drilling screws, based on size and type of head:
There are various sizes of Tek screws. The size of the drill bit is the main reason for the variation in different types of screws. The drill bit’s size determines the material’s thickness and fastening time.
Like other regular screws, the Tek screws also have different shapes of head. Flathead, pan head, hex washer head are some of the head types of self-drilling fasteners. One can also choose Philips, hex, or square drive options to drive the screw. One of the popular emerging categories is the Magnetic Head Tek Screws, since these screws can be easily driven without creating a hole, they find usage in different designs like magnetic sockets.
Screws for Metal
The self-drilling screws vary depending on the nature of the material to be drilled. The following are the types of Tek screws used to drill metal.
Hexagonal Head Full and Partly Threaded:
The purposes of these screws are fastening in metal, zinc plated or galvanised steel of 12.5mm thickness. The available sizes of these screws are 8g, 10g, 12g, and 14g.
Wafer Head Screws:
These screws used when the metal requires flat heads. The available sizes are 8g, and 10g.
Button Head Screws:
When the fastening requires a more massive hole, these screws do their job. It is available in zinc plated or galvanised sheets.
Countersunk Head Screws:
These screws are used when a flush finish is required in the metal. Available screw sizes are 6g, 8g and 10g.
Wing Drilling Screws:
These screws are used in fastening timber or other boards to metal. These screws are available as 6g, 8g, 10g, and 14g sizes.
Needle Point Screws:
The needlepoint screws fasten timber to thin metal. The available sizes of the screws are 8g and 10g.
Screws for Timber
The different type of material and thickness requires a different kind of head and size of the drill bit. Following are the different types of self-drilling screws available to fasten the timber to metal.
- Roofing and Cladding screws fasten timber into thin metal. Available in 12g and 14g sizes.
- Wafer Head Screws fastens the fixture where a flat head is required. Available in 8g and 10g sizes.
- Bugle Batten Screws fastens heavy-duty timbers where the flathead is required. Available in 14g size.
- Pan Head Screws fastens timber to thin metals where a raised head is required. Available in 8g sizes.
- Countersunk Rib Head Screws is used in fastening fibre cement where the self-embedded head is required. Available in 8g and 10g sizes.
Part of self-drilling screw:
It determined the thickness of metal where it can be drilled. The drill flute allows the material to be drilled to exit the hole.
This lies at the tip and is the unthreaded or smooth section of the screw. The length of this should be good enough for it to completely drill through the material.
The rims that you observe on the screw are the threads.
If you have to choose screw, then make sure that you have the one which has wings which should be over ½” thick, to metal. The wings act as a barrier for the threads to come in immediate contact with the hole.
While buying the self-drilling screws, make sure that you make a note of all the features and then buy the one for your purpose.
Self-drilling screws, used in metal to metal, or metal to wood applications, works best in fastening the drilling process. In case of thin metal sheets or woods, one does not have to waste time in drilling the hole. The above information would have given you a clear idea on what is self-drilling screws and what are its types.