DRAWING Z10030
T.M.N.R. AXLE BEARINGS MIKE SLATTER documents the history of the Tri-ang Minic Narrowgauge Railway axle bearings with the factory drawing. HE original TMNR axle bearings are very susceptible to wear and during my years of preserving the Tri-ang Minic system have seen many bearings in various states as a result of both use and age.
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Often, under continual heavy loads, or with the introduction of a foreign body such as dirt the internal axle hole would wear oval, and in the case of the original design the end of the axle box would break off. Various solutions have been used to overcome the wear on this original part to include the installation of roller bearings within the original unit, as documented by David Matthewson in TMNR Times 10, to the manufacture of metal units for railways that no longer use live rail by Drummond Randall. Manufactured using 'Delrin' Thermoplastic the original design for the a xle bearing by
Draftsman Ron Bulley (RHB) on the 26th October 1962 did not incorporate an oiling hole which allows the axle boxes to be dated, and are usually produced in white. The later amendment by Bill Challis (WHC) on the 4th July 1966 adds the oiling hole and nipple to the design which is more commonly seen on surviving TMNR today and can be found in both black and white varieties. With the exciting discovery of factory TMNR drawings last year, the original works drawing for axle bearings (scaled to 50% for this publication) is shown opposite.
Mike Slatter ABOVE: The original design of axle bearing on the left in white and the later design on the right.
TMNR TIMES
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