24 of the spring plate 22 when the nut tries to turn for example the nut 52 may be a rectangular threaded block as shown or the like fig3 shows a complete door and caster assembly 60 including a door 62 and the embodiment of a caster 20 from fig1 and 2 a portion of the face of the door 62 is removed to expose the caster 20 and an end plate assembly 64 the caster assembly 20 is disposed in a recessed area 66 formed in the bottom edge of the door 62 the horizontal portion 24 of the spring plate is secured to the door 62 with screws 28 a 28 d the spring plate 22 is cantilevered from the mounting screws 28 a 28 d distal from the free vertical edge 70 of the door and has a free end 72 proximate to the free vertical edge of the door because the spring plate 22 is flexible and resilient the free end 72 of the spring plate 22 may move up and down to support the door 62 and for the roller 38 to contact the floor 74 as necessary in the embodiment shown there are three steps 76 78 to the recessed area with the depth of each step from the bottom edge 80 of the door 62 increasing as the distance to the edge 70 of the door 62 decreases the stepped recessed area 66 provides space for the roller assembly it should be understood that more or as few as no steps could be used by adjusting the number of shims 32 a 32 c thickness of shims or both an embodiment of an end plate assembly.