Abstract: A model monorail system having at least one engine and at least one car coupled thereto, both being configured to move along a single upper rail member that is supported in an elevated position by a plurality of upright rail supports. In the preferred embodiment, each monorail engine assembly comprises one front wheel subassembly with a rotatable front wheel, one wheel subassembly with counter-rotating drive wheels, two weighted electrical pick-up subassemblies which are also pivotal, pivotal wheel-coupler assemblies attached to each end of each car assembly, as well as a plurality of safety arm subassemblies and a plurality of roller arm subassemblies, which together surround the upper surface, both side surfaces, and the bottom surface of the upper rail member to securely maintain the engine assemblies and coupled car assemblies in position on top of the upper rail member at all times during use.

Abstract: An asymmetrical welding ring for facilitating the end to end welding of tubes having unequal inside diameters. The welding ring is provided with an arcuate inner periphery and an irregular outer periphery divided into three distinct frustoconical surfaces.