Kato truck rollability-long

John Cathcart

List- Having messed with thousands of wheelsets and hundreds of
trucks in an effort to eliminate maintenance and maximize
rollability and reliablity on our rather large H.O. layout, I offer
what we have gleaned at La Mesa Club operations.
1. All trucks and wheels need to be 'blueprinted'; that is the
clearances need to be checked and if necessary, adjusted.
2.Many trucks will need no adjustment, ever; but allmost all
wheelsets will need to be properly gauged-initially.
3.There should almost always be some freeplay between the wheelsets
and the sideframes. Some need to be quite loose (operationally and
visually less desireable) the best will have maximum performance at
minimal clearance.
4. 'Blueprinting' wheelsets can be done on the kitchen table,
without benefit of any tools more sophisticated than your typical
model hand tools and the NMRA wheel (standards) gauge.
5. The 'blueprinting' of trucks consists of matching the sideframe
back to back distance to that of the axles of the proper taper.
6. Para 5 can be accomplished easiest by carefully (but forcefully)
bending all four 'corners of the sideframes to achieve the proper
clearance. You must overbend about 50% to allow for the 'memory'
return of the plastic. The hand use of a milling cutter to increase
the sideframe clearance (theoretically a much better idea) will not
remove sufficient material unless clearance differences are very
7. Kato trucks will always need sideframe adjustments for maximum
rollability. Improper removal of stepped axles from roller bearing
trucks (even once)will permanently ruin their rollability.
8.Kato trucks give the most rollability for the least work, but there
are many other good trucks, and many more bad ones.
9. Good rollability is the single most important aspect for the re-
liable operation of steam era freightcars- but it is not the only
There is much more, of course, perhaps another forum would be
more appropriate? Sorry for the bandwidth. Hope it helps.
John Cathcart La Mesa Club