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′ 7″ diam., 18 oval spokes, rectangular inner rim, apparent tread 4½″.
Hub 16½″ face dia., pin between at 11″, hub is 1″ out from the tyre.
Sources: Locomotives Illustrated No. 130, 'Great Central Railway 2-4-2, 4-4-2 and 0-6-2 Tank Engines.
Casting: 39.0 mm tread dia., 33.8 mm i/d, hub 0.6 mm out from the tyre, pin at 6.4 mm.
Casting prices and stock . LNER loco sets, price list
Scans of castings in a set for: GC 2-4-2T class 3, LNER F1.
8 Mar 2018