This example shows a tyre width of 3.5 mm for Gauge 0 Fine.
For other standards remove more or less metal from the back of the wheel to give your chosen tyre width.
3′ 7½″ diam., 10 rect spokes, almost flat inner rim. Apparent tread 5″.
Hub 12½″ face dia., ½″ above the tyre.
Sources: Sharp, Stewart works drawings.
Casting: 24.6 mm tread dia., 18.9 mm i/d,
hub 7.1 mm dia, 0.3 mm above the tyre.
Casting prices and stock . Netherlands, loco sets, price list
Scan of a casting in a set for a Netherlands HSM 600/NS 3200 class 0-6-0
8 Sept 2017