File cabinet dolly with open frame

A file cabinet dolly comprising a rectangular frame having four sides and composed of a generally horizontal web, said rectangular frame being adjustable along two opposed parallel sides to accommodate different file cabinet widths and including two tabbed rails, each tabbed rail located on one of said two opposed frame sides and two slotted rails, said rectangular frame comprises a pair of straight rails connected at right angles to each connected pair of slotted and tabbed rails, one end of each straight rail is secured to a different one of said tabbed rails and the other end of each straight rail is secured to a different one of said slotted rails, each slotted rail located on one of two opposed frame sides corresponding to the opposed sides on which the tabbed rails are located, each slotted rail having a plurality of spaced apart slots defining different predetermined frame widths in combination with said tabbed rail, each slot complementary to said tab to permit each tab to be secured into one of the slots and defining, in combination with said tabbed rails, a connected pair of said slotted and tabbed rails defining a predetermined frame width of said opposed sides of said rectangular frame;

• and
• means for permitting low resistance movement of said dolly over a surface comprising a castor located at each corner of said rectangular frame, said castor including a castor stud and fastening means for cooperating with said castor stud to fasten the straight rails to said tabbed and slotted rails.

A file cabinet dolly comprising:

• a rectangular frame having four sides and composed of four side members, each side member forming one of the sides of said frame, each side member having two end portions, each side member end portion secured to an end portion of another side member in an overlapping and right angle relationship to define said rectangular frame;
• a castor stud located at each corner of said rectangular frame extending through and securing, with fastening means cooperating with said castor stud, said side member end portions together in said overlapping and right angle relationship;
• and
• a depression in an end portion of one of said side members and a substantially corresponding protrusion in an end portion of another one of said side members, where said castor stud extends through said end portions, said protrusion nesting in said depression when said end portion of said one side member is secured to said end portion of another side member, wherein said depression is generally bowl-shaped and each protrusion is generally plate-shaped resulting in a gap therebetween and creating structural rigidity between each depression and each protrusion.