for GWR 4-6-0 Castle class, with later wheels at 7 mm/ft
A full set consists of 4 x B75 bogie wheels, 6 x B310 drivers and 6 x B20, tender wheels.
THE LATER LOCOS, Nos 5013 onwards were built with the 1930's wheels with reinforced spokes each side of the pin, and the gap filled near the pin (like the Kings).
References: GWR Stars, Castles & Kings, O. S. Noch: 294 - 296, build dates; Russell, Great Western Engines: fig 389, photo 5022, Wigmore Castle; Haresnape, Collett and Hawksworth Locomotices: p. 29, photo 5073, Blenheim.
The prototype driving wheel weights are surface mounted plates, and are not cast in.