How to Use a Flat Head Screwdriver

Discover the right way to use a flat head screwdriver with these simple steps.

Flathead screwdriver

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If most people were asked to name a few common tools, it's likely that hammer, saw, and screwdriver would be some of the first tools named because these tools have been in use for generations.

Screwdrivers are now available in a wide range of sizes, shapes, styles, and types, though basic Robinson, Phillips, and flat head screwdrivers remain the most common. Flat head screwdrivers, which are also known as slotted screwdrivers, have a thick handle for the user to grip, a long, rigid shafts, and a wedge-shaped flat tip, allowing it to fit into the narrow crevices of a flat head fastener. Keep reading to find out how to use a flat head screwdriver to complete projects or simple repairs around the home.

How to Use a Flat Head Screwdriver

  1. Choose the Right Screwdriver for the Task

    Before grabbing the first flat head screwdriver available, take a few minutes to think about the location you will be working in. Screwdrivers are available in many sizes, so if you know you will be working in a tight space, consider using a screwdriver with a short shaft. Similarly, if you need to access a fastener under the hood of the car or deep in the wall, then a flat head screwdriver with a long shaft may be the right choice.

    It is also recommended to consider the handle material and choose a screwdriver that is suitable for the job. Soft, padded handles are great for reducing hand strain over long periods of work, but if you only need to drive a few screws, then it may be better to use a screwdriver with a hard plastic grip that can help improve control and driving power.

  2. Ensure the Screwdriver Fits the Fastener

    Before using a flat head screwdriver to drive or loosen a screw, check to make sure that the screwdriver tip size is appropriate for the target fastener. The tool should fit the width and length of the fastener's slot as closely as possible. If the screwdriver is too big, it will not fit into the slot on the head of the screw. A screwdriver that is too small will be more difficult to use and it may strip the screw, making it hard to tighten or loosen the fastener, even with the correct screwdriver size.

  3. Slide the Flat Head Tip Into the Fastener Slot

    After confirming that you have the right screwdriver for the job and that it fits the fastener, you can slide the tip of the flat head screwdriver into the slot on the back of the fastener. Keep in mind that if you are driving in a new screw or tightening a fastener, then you will need to have one hand using the screwdriver and the other hand holding the fastener to prevent it from slipping out of position. Pre-drilling a pilot hole for the fastener can make this procedure easier.

  4. Turn Clockwise to Tighten the Fastener

    If you are tightening an existing fastener or driving a new fastener, you will need to turn the screwdriver clockwise. Hold the fastener in one hand and the screwdriver in the other hand with the flat head tip firmly set in the fastener slot. Align the shaft of the screwdriver with the fastener, then apply force as you turn the screwdriver clockwise to drive the fastener into the target material to create a new screw hole.

  5. Turn Counterclockwise to Loosen the Fastener

    If you are loosening an existing fastener, you will have to turn the screwdriver counterclockwise to unthread the screw from the hole. Make sure that the tip of the flat head screwdriver is sitting firmly in the fastener slot, then align the shaft of the screwdriver with the fastener to help prevent the screwdriver from slipping and stripping the fastener.

    Apply force to the screwdriver as you turn the tool counterclockwise. This additional force on the back of the tool helps to keep the tip of the screwdriver in position. Continue rotating the screwdriver counterclockwise to remove the fastener. Just make sure to have a loose grip on the fastener with your free hand so that it doesn't simply drop to the ground when it comes out of the hole.

Keeping Flat Head Screwdrivers Rust-Free

Flat head screwdrivers are typically made with stainless steel, so they can be used in wet conditions without a problem. However, if the screwdriver remains wet, grimy, and dirty, the material can begin to corrode. This leads to a weakened shaft and tip that are more likely to chip, warp, or snap during use.

To prevent this issue, use a clean, dry rag or cloth to wipe down your tools after use. Make sure any metal tools are completely dry, then store them safely in a toolbox or work bench until you need to use the tools for a new project or a household repair.

When to Replace Your Flat Head Screwdriver

Flat head screwdrivers are durable tools that can last for years with proper care and maintenance, but even with the best care, a flat head screwdriver will begin to wear down with regular use. The tip of the screwdriver gradually becomes thinner and may even bend or warp over time, reducing your efficiency on projects and potentially stripping screws. With additional strain, the tip of the screwdriver can chip, crack, or shatter entirely during use. Similarly, the shaft of the screwdriver is susceptible to bending, warping, and breaking after years of regular use.

Look for signs of degradation, like rust build-up, difficulty turning fasteners without slipping, or even a cracked handle. If you notice the screwdriver isn't performing its function as well as it once did or it shows signs of damage, then it's time to invest in a new flat head screwdriver.