Re: Semi-Scale Wheelsets for IMRC 70-Ton Trucks


Denny Anspach <danspach@...>
 

It is not at all unusual that any given molded styrene truck may optimally require two different axle lengths for best operation. This disparity can vary from one molding machine to the next, and in fact can vary from one batch of trucks to next from the same machine. These trucks are not precision instruments, and if they were manufactured to be so, no one of us could afford to purchase them!

Usually, the difference between the required lengths is slight, and one can simply choose a compromise axle length that will work with no discernible decrease in rollability, or perhaps even more importantly, any excess end play.

Occasionally, a tiny metal sliver at the point of an axle (a common byproduct of being made on screw machines) can create the false effect of an axle of given length being "too long". This can be felt by the pad of a finger, and very easily removed by several gentle swipes with fine grit sanding board (I use a 1000 grit).

Although I use the Reboxx reaming tool (sparingly), using it to alter required axle length can be pretty chancy, actually making things worse.

BTW, all the same issues hold for cast metal and brass trucks. They too are not "precision instruments".

Denny

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