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Self—tapping screws and screws are the most common types of fasteners. An inexperienced person can simply confuse them because of their external similarity. But the scope of application of screws and self-tapping screws is different.
The main differences between a self-tapping screw and a screw:
1. Appearance. Both the self-tapping screw and the screw have the appearance of a rod with an external thread and a cap on the top. But the self-tapping screws have a sharper and higher thread.
2. Carving. At the self-tapping screw, the turns of the thread are applied to the entire rod all the way to the cap. This is done for better fixation in the material when twisting, which is especially convenient when fixing thin sheets. The screw has a smooth rod under the cap.
3. The material of the products. Self-tapping screws are made of hard steel alloys that have undergone heat treatment, which gives them high strength. Soft types of steel are used for screws.
4. Preparation for work. A hole must be pre-drilled under the screw, into which it is then screwed. This is not necessary for a self—tapping screw – it is immediately screwed into the material. Due to the sharper edges of the thread and the tip of the rod, the self-tapping screw cuts a hole, and the thread penetrates its walls.
5. Application. Screws are mainly used for working with wood. A self-tapping screw is used as a fastener for parts made of wood, plastic, metal, drywall, concrete. The length of the thread on the rod depends on the thickness or number of parts to be connected.
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