This example shows a tyre width of 3.5 mm for Gauge 0 Fine.
For Scale7 remove more metal from the back of the wheel to give a tyre thickness of 3.2 mm instead of 3.5 mm.
7′ 7¼″ diam., 22 oval spokes, apparent tread 4½″.
Hub 16½″ face dia., 2 5/8″ out from the tyre.
Casting: 53.4 tread dia., 48.0 i/d., hub 1.5 mm out from the tyre.
Source: N.E.R works drg. No. 4029 of April 1910.
Casting prices and stock . NE loco sets, price list
Scan of a casting in a set for a NE 4-4-0 Q1 class.
27 Mar 2013