A hex screw is a commonly used fastener on several machines and electronic devices. These types of screws have a hexagonal opening in the head with a standard or metric measurement. The openings are made to fit hex-key wrenches used to tighten or loosen the screws. The fasteners are typically removed for replacement of parts, or to access certain parts for maintenance operations. Loosen and remove hex screws easily with the correct tools.
Insert the long end of various hex-key wrenches into the hexagonal slot of a hex screw until you find a wrench that fits into the slot. Fastener slot sizes are often difficult to judge by sight, so this may be a trial-and-error process.
Check the fit of the key wrench by turning it slightly to either side with gentle pressure. The correctly fitting key will not have any play within the fastener head. Try key wrenches from metric and standard sets to find one that fits precisely.
Turn the hex-key wrench in a counterclockwise direction to loosen the fastener. Insert the short end of the wrench into screws that resist loosening for greater turning leverage.
Use pliers to aid in turning a key wrench for screws that are firmly stuck. Use a hammer to tap against the hex-key wrench in extreme cases. Pour a few drops of household oil or spray a shot of aerosol lubricant on screw heads that do not come loose with the additional tools. Allow 20 minutes for the lubricant to work in between the threads before attempting removal.