What’s the distance between the rails in the real world? And in HO scale? I know I can just measure my HO scale track * 87.1 but I want to know the exact distance.
HO scale track is 16.5 mm, at 3.5 mm to the foot this works out at 56.571428 scale inches as near as dammit to standard gauge-4 ft 8.5 inches.
Thanks John, appreciated.
Electrolove,
For more than you ever wanted to know about full scale track gauges, try:
http://turksib.com/gauges/index-e.html
click on link
Caution - LINK SITE HAS PROVEN TO BE A CHANGEABLE TO SALES - ADVERTISING SITE - ORIGINAL INFO NOT ACCESSIBLE if link clicked directly.
(Edited Monday, 14 Aug 06, 9:38AM)
Chuck (found at 762mm and 1067mm, but not at 1435mm)
4 feet 8.5 inches is standard gauge.
In curves, sometimes it is widened slightly (1/2" to 1") to get to trains thru without derailing.
If it is more than say 2" wider, that is called wide gauge. Usually found at derailment sites. [}:)] The rails spread, and down you go.
For we’uns its fifty-six and a half inches; for you’uns its one meter, forty-three and a half centimetrs.
For we’uns HO-Gauge is sixteen and one half millimeters; for you’uns HO-Gauge is sixteen and one half millimeters - isn’t that absolutely amazing. Keep one thing in mind, however; gauge is not measured from the inside of one rail to the inside of the other rail; it is measured from the inside of one rail to the OUTSIDE of the other rail. More accurately - but this gets a little hard to measure - its from the center of one rail to the center of the opposite rail. That’s because of the thickness of the top of the rail whatever its called. PICKY! PICKY! PICKY!
This 16.5 mm works out to .650 inches, a figure often quoted as the track gauge; that works out to 39/60ths of an inch. This can be measured with an architects scale but I can tell you where you are going to wind up if you try to do it that way; try for outside privileges on Saturdays so you can go train watching. However you cut it 16.5 mm and/or .650 inches are nerve-racking measurements to say the least; this is why Kadee and Micro Engineering make track gauges in HO and Micro Engineering makes a track gauge in N. Kadee/Micro-Trains - old habits die hard - includes a coupler height/track gauge in their coupler starter kit.
I have to disagree. NMRA standards diagrams clearly show inside of rail head to inside of rail head as the measuring point. The NMRA gauge measures the same way. I would want convincing proof the prototype does not do the same. Rail head thickness is not standardized in either the model or the prototype; it usually varies with rail height. Therefore, measuring gauge anywhere except inside rail head to inside rail head would be inconsistent with a single spec, and difficult to keep consistent. I do remember reading that modern prototype practice does not allow the gauge to get more than 1/2" wide because of increased wear and other problems.
my thoughts, your choices
Fred W
I agree. It has to be from inside to inside. The width of the rail doesn’t really matter as long as it is at least “enough”, and would change the center to center measurement. The spacing of the flanges on the wheels and the didtance from inside to inside of the rails are the critical measurements.
there’s also a story behind the 4’ 8 1/2"…back when the country was young there were railroads popping up all over the place…each railroad would custom build their own locomotives, rolling stock, and track gauge…you can see the problem this caused…say you wanted to ship goods from one part of the country to another which might mean that you may have to ship it on four or five different railroads because one railroads track gauge was different from another’s and each other’s equipment wouldn’t fit on each others rails …can you imagine the cost and the time it took for loading and unloading the goods from one railroad to another and another and so forth until your goods were moved to it’s final destination?..so to streamline the operation, ol’ Abe Lincoln inacted a bill that would standardize the nation’s rail gauge…the standard would be 4’ 8 1/2"…the width between the wheels of the old Roman chariots…chuck
FYI - the Royal Gorge was originally designed and graded as standard gauge (for the AT&SF), but then the D&RGW got possession and laid 3 foot narrow gauge through it. It was dual guaged in 1887 (To capture California traffic after the UP shifted its Pacific traffic from the CP). It remained dual gauge until 1911.
Everyone here has left out narrow gauge altogether. There are more more than just the standard track widths. Much more.
This is worth a look:
“Keep one thing in mind, however; gauge is not measured from the inside of one rail to the inside of the other rail; it is measured from the inside of one rail to the OUTSIDE of the other rail”
Where do people come up with this rubbish?
I’ve always thought that the measurement was taken from the center of the top of the rails. Seems like that would make the most sense.
Howdy:
If I may add my 2 cents worth, here is what I found on the Web regarding the origin of the 4’-81/2" standard:
From: Professor Tom O’Hare, University of Texas
Subject: Mil. Specs
How Mil Specs Live Forever
The US Standard railroad gauge (distance between the rails) is 4 feet, 8.5 inches. That’s an exceedingly odd number. Why was that gauge used? Because that’s the way they built them in England, and the US railroads were built by English expatriates.
Why did the English people build them like that? Because the first rail lines were built by the same people who built the pre-railroad tramways, and that’s the gauge they used.
Why did “they” use that gauge then? Because the people who built the tramways used the same jigs and tools that they used for building wagons, which used that wheel spacing.
Okay! Why did the wagons use that odd wheel spacing? Well, if they tried to use any other spacing the wagons would break on some of the old, long distance roads, because that’s the spacing of the old wheel ruts.
So who built these old rutted roads? The first long distance roads in Europe were built by Imperial Rome for the benefit of their legions. The roads have been used ever since. And the ruts? The initial ruts, which everyone else had to match for fear of destroying their wagons, were first made by Roman war chariots. Since the chariots were made for or by Imperial Rome they were all alike in the matter of wheel spacing.
Thus, we have the answer to the original questions. The United State standard railroad gauge of 4 feet, 8.5 inches derives from the original specification (Military Spec) for an Imperial Roman army war chariot. MilSpecs and Bureaucracies live forever.
Regards,
the goat
Do you know how they measure the gauge out in the field? I didn’t think so because if you did, you wouldn’t ask the above question.
They use a steel track gauge, that is placed between the rails. So much easier than centre to centre.
See my comment above about railfans not knowing how real railways work.
However, you do raise in interesting point regarding centre to centre. I have a theaory that we arrived at 4ft 81/2inches because the original rails were measured centre to centre. It was only later that they began to measure the inside gauge, hence the oddball 4ft 81/2".
Nothing to do with that old urban myth abpout Roman chariots and the width of horses rear ends.
Standards S-3.2 and 4.2 have what is called an abstraction or abstract inference to it. Standard S-3.2 (Trackwork: Standard Scale) sets the maximum track gage for HO-Scale at .672 inches/17.1 millimeters. Standard S-4.2 (Wheels: Standard Scale) sets the maximum check gage at .605 inches/15.37 millimeters. I will gee-go-guarantee you that if you build to minimum track gage (.649 inches/16.5 millimeters) and you use minimum check gage for your wheels and you do not use minimum flange widths you will, very shortly learn how to spell d-e-r-a-i-l-m-e-n-t-s-a-t-f-l-a-n-g-e-w-a-y-s.
And that’s all the rubbish I have for the day there, rogertra; certainly hope that I didn’t use too big a words or too long a sentences. Before closing I do have to ask, which is better, Atlas or Kato?
SEE DICK!
SEE DICK RUN!
SEE DICK RUN FAST.
SEE ROGERTRA ASK, “WHAT DOES ABSTRACT MEAN? WHAT DO HISTORY MAJORS AND COMPUTER PROGRAMMERS DO? WHAT DOES THINKING ABSTRACTLY MEAN?”
This old CPR track spec diagram clearly shows gauge being measured inside the rails.
http://railways-atlas.tapor.ualberta.ca/cocoon/atlas/Charts-5-3-9/
(use the icons at the bottom of the diagram to expand the diagram or move the image around)
Regards
Ed
What on Earth are you babbling about?
We were discussing how real railways measure gauge, "Between" the rails, not NMRA standards.
How was disussing what history majors and computer progammers? What have they got to do with a railway measuring gauge?
Wierd.
No, I didn’t know how they were measured in the field. I didn’t ask a question, either. I just said what would make sense to ME.