support means 6 the corner joint 2 may be of a variety of construction as will be explained hereinafter depending upon its specific use and location it consists of a block 8 and at least one flange 10 extending from one surface of the block 8 an aperture 12 is cut through the flange 10 when the hinge mechanism is assembled flange 10 is inserted into the slot 14 which is formed by arms 18 20 until the aperture 12 is aligned with aperture 16 the split pin 22 is then inserted through the apertures 12 16 to secure the components together as shown in fig2 since the split pin 22 is machined to fit snugly in apertures 16 12 it secures the flange 10 to the arms 18 20 since the split pin 22 is marginally compressible it can be forced into the apertures 12 16 and under slight compression it applies pressure outwardly to the flange 10 and the arms 18 20 thus providing a tight fit also since the outer end 24 of the flange 10 is rounded it can pivot about the pin 22 without contacting the inner surface of the slot also since the outer ends 19 21 of arms 18 20 are rounded the pivotal support means 6 can also pivot without the ends 19 21 of the arms 18 20 contacting.