I am investigating my options in running some Gauge 1 trains indoors, and given my affection for the quirky early 20th century style I thought I would investigate the use of Bassett Lowke’s “Lowko” track.

Wheel Standards

“Greenly” wheel standards from the 1920’s are not a million miles away from current standards, given the need to accomodate vintage live-steam stock that is typically not a concern in smaller-scale modelling.

The following illustrates the difference in the No. 1 Gauge standards from the Greenly text above, with those published by the Gauge 1 Model Railway Association:

In terms of meaningful difference, the B2B is approximately 1.25mm wider in modern standards, the flange is approximately 1.25mm smaller and the tyre is overall 1mm more narrow.

This overall results in a proportionally thicker wheel with a larger flange.

Track Standards

While the nominal gauge of both the Greenly and G1MRA standards is effectively identical, there is a significant difference in the geometry of the turnouts themselves.

The major concern is around the relationship between the check gauge and the corresponding B2B+Flange. While there is internal consistency in the standards, there is a clash in running modern stock on vintage track, in that the B2B+Flange of modern stock is 41.5mm, while the check gauge of BL track is 38-40mm.

This means that modern stock cannot be guided effectively by a BL check rail, and will ‘split’ the vee and derail.

Fixing

Often a resolution for running finer scale stock on coarse track is to pack out the area underneath the vee, so that the flange of a wheel (rather than the tyre) carries it through the gap.

As can be found from the previous discussion however, narrowing the check gauge is the primary concern – it must be narrowed by shimming the check rails by 2mm – illustrated below with a 2mm lolly stick in the flange-way:

It would appear the Bassett Lowke track I have to hand has been cared for but repaired over time, and the actual flangeways vary from 3.9mm to 5.5mm!