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.
3′ 0″ diam., 10 oval spokes, rectangular inner rim, apparent tread 4″, tyre width 5″.
Hub 11″ face dia., 1½″ out from the wheel.
Casting: 21.0 tread dia., 16.2 i/d., hub 0.9 mm out from the tyre.
Casting prices and stock . GWR loco sets, price list
Scan of a casting in a set for GWR 4-6-0 Grange . GWR 4-6-0 King
27 Mar 2013