The online magazine on the history and operation of vintage scale model trains in American OO gauge

Tuesday, July 13, 2010

“OO” Railway Notes: F. D. Grimke and his Series on OO Gauge, 1931-32. Part II: The Wheel Problem

Turning from the topic of track as covered in part I of this series, in May of 1931 F. D. Grimke wrote,
And now the most important problem to solve in the majority of model railway problems is the Wheel Problem.

It was discovered that there were not suitable wheels on the market. The ones that one can pick up in England are not suitable to conditions on this side of the ocean. It is true that one can obtain both driving and car wheels, but more often than not they cannot be used. Therefore it was necessary to manufacture them.
Following this Grimke outlines the sizes most needed, three sizes of drivers 79” (23.5mm), 63” (20mm) and 56” (18mm) and also 36” (12mm) and 33” (10mm) wheels for trucks (that last metric number catching my eye as a misprint, 11mm would have been correct). The drawings by Thuillgrim Models that were published with the article in the May, 1931 issue of The Modelmaker are these, which show wheel and flange standards and also axles (click on the scan for a bigger view). On making axles and wheels he wrote,
The Axles are made from 3/16” and 1/8” Drill Rod with 1/8” and 1/16” shoulders respectively….

The 12mm and 10mm dia. wheels are turned from round brass bar stock, and if the usual methods are followed, there should be no unusual difficulties. These wheels should be oxidized by sulphur. This will turn the color to that of tempered steel, and incidentally will give a better factor of cohesion between the wheels and the rail.
In short, to build 4mm scale models in 1931 you would have needed to have been enough of a machinist to make your own wheels following the plans in this issue.

On the inside back cover of this issue is an advertisement by Thuillgrim Models which lists as available seven different standards sheets. The scan in this post would seem to be the A7 sheet and these were also referenced in part I. Priced at 25 or 50 cents each, the full list was:

A1 Single Track Standards
A2 Double Track Standards
A3 Track Standards
A4 Frog Standards (see part I)
A5 Crossover and Switch Stanadards
A7 Wheel and Axle Tolerances
A8 Wheel Standards

When we return to this series we will get down to the business of building a locomotive.

Continue in 1931-32 series

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