London Banter - View Single Post - LUL track gauge not the same as BR gauge?

Acrosticus · September 2nd 04, 06:00 PM posted to uk.transport.london

From: (James)
Date: 02/09/2004 15:43 GMT

Regular 4'8½" gauge track actually varies in gauge between 4'8¼" and
4'8¾" depending on track curvature. If you think about it, this
difference of half an inch between minimum and maximum is actually a
quarter inch on either side - a wholly insignificant amount. If stock
which has wheels ¼" further apart tries to run on such rails, there
are likely to be no problems, although they may end up riding on the
wheel-flanges. As to whether that statement is true, I have no idea.

"Regular" track as you call it ("plain line" as PW engineers term it) might not
be too much a problem if you're ¼" tight or wide to gauge - although it
probably wouldn't ride too smoothly. It becomes a rather serious problem though
when going through pointwork, where flanges ¼" wide to gauge may try to
"wrongside" the frog for example; failing which they'll probably bash its nose
to pieces in no time instead.