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The next six photos are the truss rods applied to the countershaft brackets, and new brake beams.
Two of these large castings mount parallel to the crankshaft, and are the supports for the countershaft, which receives the power from the crankshaft through miter gears, and in doing so converts the drive shafts into a fore-and-aft orientation. In the era that the 1551 was built, these castings were poured of cast-iron, which is weaker than steel, thus requiring truss rods to ward of breakage. The upper rods, twins, are 3/4-inch diameter; the bottom, single, is 7/8-inch diameter.
Here Lou is straightening one of the twins. If one studies the fine points of the configuration of the main casting, one can see that the installation of the twins is not a simple exercise in heating the rod and bending it to a "V" (like was done to the big rod). The twins were inserted from one end, and advanced to the point that the amount of rod beyond the pivot point was not too long to allow the end of the rod to swing and start into the hole in the curvature of the casting. The rod was advanced by simultaneously bumping it on the end (thus the protective nut over the threads), and beating it down around the pivot point. This was done while the rod was at forging temperature, not cold. All rods were made too long, to allow for trimming in case any threads were destroyed during these rude operations.
Photo by Rick Brigger