LEARNING MATERIALS 4.1 Technology & Livelihood Education Grade VIII Name: _________________________ SCREWS Screws are another kind of fastener which is stronger than nails. It is characterize as short, slender, sharp-pointed metal pin in general with a raised helical thread running around it and a slotted head. It is used to join things together by being rotated so that it pierces wood or other material and is held tightly in place. Screws are driven by screwdriver and other related tools that fits to the head. In purchasing screws, one has to remember that the measurement of the length of a flat screw differ from the oval head screw. Length of a flathead screw is measured from the top of the head up to the tip as the head will level to the surface of the wood. The measurement of the oval head screw is from the bottom of the head until the tip of the thread as the will be exposed. Common Types of Screws 1. Wood Screw – It is the most common type of screw. Wood screws aren’t made on the actual wood. Rather, they are used to connect two or more solid wooden objects. It has a sharp point to dig into the wood, making them highly useful to woodworking applications. 2. Machine Screw – As the name suggest, it is used in machining applications. These screws are unique because of their size. driven square or hex drive head. It features coarse threads and a tapered point. It's typically much more heavy-duty than conventional wood screws that are fitted with slotted heads. 3. Lag Screw- is a sturdy screw often with an externallydriven square or hex drive head. It features coarse threads and a tapered point. It's typically much more heavyduty than conventional wood screws that are fitted with slotted heads. 4. Sheet Metal Screw - is a kind of hardware supply, which is used tightening metal objects. This kind of fastener features a threaded shank along-with a flat/rounded head. Unlike wooden rivets, which are threaded only partially, the above mentioned screw's shank is entirely threaded. 5. Twinfast Screw - also known as particleboard screws. Have a coarse thread with twice the thread pitch of standard wood screws,making it easy to drive them into a variety of materials such as chipboard or various densities of fibreboard. 6. Security Screw - also known as tamperproof screws, are otherwise standard screws but with a unique head, making it nearly impossible to remove with common tools. That used to mean that any screw that couldn't be removed with a slot-style or Phillips head driver could be considered a security screw. Screw heads differ as to the kind of application or where the screws are to be used. It is important that the kind of screw to be used will fit to work. Below are the different screw heads to know when purchasing screw. SCREW DRIVES Drive is the formation of the head slot where the tool used in driving the screws is inserted. It should be fit to the formation of the drive or else the drive of the screw will deformed. The most common tool used to drive the screw is the screwdriver. The Parts of a Screw Miscellaneous Screws Screw Eye Hook & Eye Cup Screw Screw Hook L-Screw Miscellaneous screws are used in household/offices for hanging objects. _____________________________________________________________________________________ Instruction: Write your wrritten activity on this learning materials only. This activities will due on May 24, 2021. Please drop on the box in T.L.E. on or before the specified date. 1. Identify the tools used in driving screws and how they are used. Name of Tool How the Tool is Used 1. 2. 3. 4. 5. 2. In a 12” x 12” hard material, Get a sample on the different kinds of screws including the miscellaneous screws. Put a label on it.
