6′ 8″ diam., 20 oval spokes, rectangular inner rim, 4½″ apparent tread, tyre width 5¾″.
Hub 18½″ face dia., 1¼″ out from the tyre. Pin between at 11″.

Source: No 251 measured direct at NRM, York in August 1995.

Casting: 63.5 mm tread dia., 56.6 mm i/d, hub 1.2 mm out from the tyre, pin at 8.7 mm.
Tyre width for for exact scale models at 32:1, 5¾″ = 4.6 mm.

Casting prices and stock . GN loco sets, price list

Scan of the castings in a set for a GN 4-4-2 Atlantic