Tag Archives: metric fastener
Tamper-proof screws are designed to prevent the dismantling of the products they hold together for safety and/or security reasons. Design developments have made it both difficult to unscrew some fasteners, and easier to determine if a screw has been interfered with. These “tamper-resistant” and “tamper-evident” options have an important place in making products such as electronics, safety devices, security systems, etc., safer, more secure, and less susceptible to vandalism and unauthorized “adjustments.”
The Tamper Resistant Design
Tamper-resistant screws are labeled as such, because their unconventional drive slots require specialized tools to engage and turn them. Holes, notches, and odd geometric shapes are commonly used as drive slots, and can only be driven with their corresponding tools. The theory is that thieves and vandals may keep slotted and Phillips screwdrivers among their burglary tools as a matter of course, but they are unlikely to have access to spanner or Torx drivers when the opportunity for malfeasance arises.
Like most aspects of construction and manufacturing, choosing the proper tool for the job goes a long way toward determining the project’s success. Selecting a metric fastener’s drive recess (the slot or hole into which the driving tool is inserted) is no different. Drive recesses, from Phillips head screws to more unusual shapes and specialized uses all have advantages and disadvantages. Take a look at some of the drive types Mr. Metric offers to learn about which style is right for your job.
Ensure Proper Tightening & Removal of Metric Fasteners With the Right Drive Type
Slotted – The first and still one of the most common varieties, slotted metric screws are inexpensive and come in virtually any head shape desired. They are also the easiest to torque when using a screwdriver to remove corroded or frozen fasteners, so they are often used when field installation and/or removal is necessary. However, they are unsuited for automated driving because the single slot allows the bit too much tolerance, and slippage and off-center engagement can occur. Continue reading