I appreciate your concerns that the standards relate to the wheels
you originally produced, so I thought it would be useful to
measure my locos and rolling stock which use other types wheels.
Results are:
Wagons - mainly Alan Gibson OO wheels re-gauged (I'm assuming
these are RP25) - 12.4mm
Manning Wardle 2-6-2 -? Alan Gibson wheels intended for the 7mm
L&B kit - 12.4mm
Baldwin 4-6-0 - very old Alan Gibson wheels intended for OO/EM -
12.4mm
K1 Garratt - coarse Romford/Markits wheels on 14mm axles
re-profiled with Scale7 tool - 12.3mm
From the above I would
assert that the modern fine RP25 standard wheels set to 12.4mm
will work just fine.
Interesting the B to B part of my old RCL standards gauge
(which O confess I rarely use) seems to measure at 12.6mm. I don't
believe my 15 year old (but carefully looked after) Mitutoyo
vernier caliper is at fault.
