When the hinge breaks on your favourite shades, you don't need to immediately buy a new pair. Sunglasses hinges can be made at home. Basic sunglasses hinges have two separate sides consisting of a leaf and a barrel. The leaf is the flat area that attaches to the sunglasses frame and the barrel is the tube for the screw that holds the hinges together. Read this guide to learn how to repair sunglasses hinges with jewellery-making tools.
Draw the basic template for the hinges on the brass shim. Draw two rectangles, 1/8-inch vertically and 1-inch long horizontally with the ruler and thin Sharpie. Draw a line down the centre of the rectangles vertically, dividing each into two rectangles, 1/2-inch long.
Cut the basic metal hinges. Clamp the brass shim in the table vice with the drawn templates on the outside. Saw the four templates following the Sharpie lines to create four metal rectangles, 1/8-inch by 1/2-inch each.
Draw the template for the barrel tongue on the four basic hinges. Draw a line dividing each hinge vertically, 1/4-inch on either side of the line. Draw a second line on each hinge dividing it horizontally from one end to the centre vertical line to form two 1/16th-inch by 1/4-inch rectangles on one side of each hinge.
Clamp one of the hinges to the table vice with the drawn area on the outside and saw one of the 1/16-inch by 1/4-inch rectangles out of the hinge to form the barrel tongues. Smooth all sharp edges with the fine metal jewellery file. Repeat with the other hinges.
Roll the barrel tongues. Bend the far tip of the barrel tongue of one hinge around one side of the round-nose jewellery pliers with the flat jewellery pliers and wrap until the rolled barrel is flush with the end of the leaf. Repeat with the other hinges.
Pair the hinges. Lay two hinges barrel-roll side down and intersect the barrels. The flat sides will attach to the end pieces and temples of the sunglasses. The end pieces are the parts at the corners of the frame front where the hinges connect and the temples are the arms that extend to the ears. Repeat with the other two hinges.
Clean the sunglasses, hinges and two screws with rubbing alcohol and a paper towel.
Insert the screws into the hinges and apply a dot of epoxy to the top and bottom of the screw to hold it in place. Allow to dry.
Apply epoxy to the flat backs of the leaves of the hinges and the end pieces and temples of the sunglasses. Press each hinge in place then clamp each leaf to the frame with spring clamps. Allow to dry.