phillips head screws came into use in 1936.
when did phillips head screws come into use?
1936
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by design, torx head screws resist cam-out better than phillips head or slot head screws. whereas the tendency of phillips drivers to cam out under excessive torque has been listed as a feature preventing damage to the screw-head or driver, torx heads were designed to "prevent" cam-out. the development of better torque-limiting automatic screwdrivers for use in factories allowed this change. rather than rely on the tool to slip out of the screw head when a desired torque level is reached (which risks damage to the driver tip, screw head, and/or workpiece), torque-limiting driver designs achieve a desired torque consistently.
torx