I bought the HO NMRA track gauge and have received instructions from Joe Fugate on the importance of several critical dimensions. The problem is that I cannot decifer some instructions on turnouts. For example dimension “W” is very important but I do not know where it is on the gauge nor where to put the gauge on the turnout. I need a “from here to there” dimension and where that dimension is located on the turnout. Same for points measurement. Can anyone put this in simple terms so I might see if my turnouts are in proper order?
Bruce - would this help? http://www.nmra.org/standards/gauge.html I agree it can be vague or confusing. J.R.
You should have received instructions with the gage. The instructions are pretty good, IIRC, at explaining where each critical dimension is to be checked… And I think “W” may be for the wheel tread width? (Not sure, so don’t bet the farm on it…) The gage measures much more than track components…
There’s a very good video on the Fast Tracks website that explains in excruciating detail how to use the NMRA gauge to check various turnout dimensions. Check it out at
http://www.handlaidtrack.com/nmra-online.php
Edit: I believe the “W” refers to the Wing Rail. The measurement(s) in question is(are) between the wing, guard, stock, and frog rails. See section 2 on the NMRA RP2 page that Jeff linked to above.
stokesda, that video says a lot for me. I did not realize that some dimensions were max while others are min. The drawing I got with my NMRA gauge is so fuzzy as to be unreadable. I downloaded the NMRA website instructions and they are better but far from good.
Thanks for the link.
Bruce:
W is wheel tread width, and is a derrived dimension from N, tire width:
W = N - T
where:
W is tread width [N is the tire width, that is the width of the entire wheel, from its face to its back, including the tread width (W) and the flange width (T)]
N is tire width (entire wheel width)
T is flange width
The NMRA gage has a tire width slot on the upper left in the No-Go area between the wheels and flangeways section to check N. The wheel must not drop into the slot or it is too narrow.
The Wheels section of the gage tests T (flange width) and D (flange depth). As long as the wheel flange fits into the wheel flange slot in the wheels section, then the flange is not too wide nor too deep. This means the derrived dimension, W, will be within tolerance because N and T are within tolerance and W = N - T.
Make sense?
It’s all coming together now…thanks to all of you. You make this hobby much more than just reading a magazine (or three). Thanks again,
Bruce,
Thanks for this thread. I have also found the gauge to be incomprehensible… even with non-fuzzy instructions. All this info helps.