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.
5′ 8″ diam., 18 oval spokes, rectangular inner rim, 4″ apparent tread.
Hub 16½″ face dia., 1½″ out from the tyre, pin in line at 15″.
Sources: Works drawing No. 57236, Swindon April 1919, for Lot 214, No 4700.
Casting: 39.7 mm tread dia., 34.9 mm i/d., hub 0.9 mm out from the tyre, pin at 8.75 mm.
Casting prices and stock . GWR loco sets, price list
Scan of the castings in sets for a GWR 47xx
27 Mar 2013