Self-Tapping vs. Self-Drilling Screws: Do You Know the Difference?
What Are Self-Tapping Screws?
Self-Tapping screws tap their own thread, so they need a pilot hole slightly smaller than the screws diameter. The idea is, you drill a pilot hole into wood or another soft material. Then as you drive the tapping screw in, its threads will dig into the material keeping it secure. Self-Tapping screws are ideal for all sorts of materials, including wood, metal, and brick. For harder surfaces, Self-Tapping screws might have little notches on the thread to help cut the thread, just like a tap. Keep in mind, not all tapping screws have a pointy tip, some will be blunt or flat. Self-Tapping screws save time and money by eliminating the need for a tap. They also are more precise in that they resulting threading they create is much more precise and creates a tighter stronger connection.
What Are Self-Drilling Screws?
Self-Drilling screws are exactly what their name says they are – self-drilling. These screws work as both a drill bit and a fastener. Self-Drilling screws do not need a pilot hole because of the drill bit end. They work very well at fastening thin pieces of metal together and were designed for that reason. They also have much variance in types and uses than tapping screws. Self-Drilling Screws are almost always made out of hard steel or some metal that has been treated to increase its hardness. When using Self-Drilling screws, make sure the material you drill into is softer than the screw material itself. Otherwise, the screws drilling tip will dull and not cut into the material.
Self-Drilling screws are a time saver eliminating both the steps of drilling (in most cases) and tapping a hole prior to installation. This also eliminates the need for drill bits and taps and switching between them for each hole.
So, Which Is Better?
In the world of fasteners, the usual answer for which is better comes down almost entirely to the situation the fastener is being used for. From a time saving point of view, a Self-Drilling screw is the better choice because it can eliminate the need for a drill bit making installations a one step process. However, both have their place and it comes down to knowing which to use in the situation at hand.
Martin Fastening is a proud member of the National Fasteners Distributor Association and can provide a custom-tailored solution for the procurement of all your fastening needs to help lower your total cost.
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