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COMPATIBILITY - wheels on other tracks

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G1MRA STANDARD
Where you can run your stock:
STANDARD WHEELS WILL NOT RUN on FINE, ScaleOne32 or dead scale track because the wheels will bind or climb over the checkrails.

What will run on your track:
STANDARD TRACK WILL ACCEPT wheels any of the finer standards, though they will not be supported by the check rails and may pass the wrong side of a point tip. Small wheels, narrower than standard wheels are more likely to drop in the long wide gap at the frog.


G1MRA FINE
With wheel flanges 1.0 mm wide and a back to back of 42 mm.

Where you can run your stock:
FINE WHEELS WILL RUN on track down to a dead tight fit at 44 mm. track gauge on straight track (less possible on curves).
FINE WHEELS WILL RUN through STANDARD points, but the wheels are too far apart to touch the outer check rail and they may derail by going the wrong side of the frog especially in facing points. If the STANDARD running rails are less 45 mm, there is a risk of long wheel base Locos derailing on curves. If in doubt test it slowly at first.
FINE WHEELS MAY NOT RUN on ScaleOne32 as the wheels are likely to bind on the check rails (exact fit with nothing to spare).
FINE WHEELS WILL NOT RUN on dead scale track as the wheels will bind on the check rails.

What will run on your track:
FINE TRACK WILL NOT ACCEPT standard wheels as they will bind on the check rails.
FINE TRACK WILL ACCEPT finer wheels and give opposite check rail guidance to ScaleOne 32 wheels.
FINE TRACK WILL ACCEPT dead scale wheels but without opposite check rail guidance, though having a relatively short and narrow gap at the frog this does not cause problems as long as the wing rails line up correctly with the frog. If the wing rails are at a wider gauge than the frog there will be derailments. Slightly narrower is better than slightly wider.


Proto:32 and ScaleOne32
With wheel flanges 1.0 mm wide and a back to back of 42.2 (to 42.3 mm. in Proto:32).

Where you can run your stock:
ScaleOne32 WHEELS WILL RUN on FINE track with accurately made points (see above under 'fine').
ScaleOne32 WHEELS WILL RUN on dead scale track but the wheels will only have 0.1 mm spare clearance over the check rails.

What will run on your track:
ScaleOne32 TRACK WILL ACCEPT dead scale wheels.
ScaleOne32 TRACK WILL NOT ACCEPT FINE, wheels will bind on the checkrails unless the fine wheels back to back is widened to 42.2


Dead Scale (almost) at 1:32
With wheel flanges 1.0 mm wide and a back to back of 42.27 to 42.56.

Where you can run your stock:
Dead scale WHEELS WILL RUN on ScaleOne32 track and on FINE track. On FINE track, in theory with rectangular block diagrams, the base of the flange is not held fully off the tip of the point. In practice, since the flange root radius overlaps the rail top radius, it does seem to work. With Fine and the finer standards, without the excessive loose slop of the Standard standard, wheels are quite well steered by the track and less likely to try to run sideways into the frog gap. As long as the track does not narrow as you pass from the wing rail to the tip of the frog there should be no problem.

My own outdoor track still has Gauge One Fine pointwork. All the rolling stock now in use has scale flanges and back to back. The flangeways have not been narrowed which means that the check rails are not contacting the wheels (at 42.5 b-b). It would seem that correctly lined-up wing rails are sufficient to guide the wheels through the point frogs.

What will run on your track:
Dead scale TRACK WILL ACCEPT ScaleOne32 stock.
Dead scale TRACK WILL NOT ACCEPT FINE or STANDARD wheels as they will bind on the check rails.


G SCALE
Where you can run your stock:
G SCALE (Aristocraft, LGB, USA Trains etc) with a back to back of about 39.5 will run through STANDARD points though this could be a tight fit where the check rail span is at the G1MRA maximum allowed 39.5 mm.

G scale wheels are of a coarseness which matches the track and may be over 7.0 mm wide, so not dropping-in on the points.

In some makes the flanges are 3.0 mm deep and may foul the chairs or even the rail clips on flat bottomed track.
G scale WHEELS WILL NOT RUN on any track finer than G1MRA Standard.



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