From: mac@cis.ksu.edu (Myron A. Calhoun)
Newsgroups: rec.models.railroad
Subject: Final word (from me) on SCALES and GAUGES
Date: 6 Nov 92 20:00:16 GMT
Article-I.D.: depot.mac.721080078
Distribution: na
Organization: Kansas State University, Dept. of Computer Science
NNTP-Posting-Host: depot.cis.ksu.edu

This is the FINAL DRAFT, at least as far as I'm concerned!

If there is an official "Keeper of the FAQ", s/he is welcome to
snarf this and do whatever s/he wishes with it.

Please remember that, except for typing mistakes, I did NOT originate any
of this; I've merely tried to colate and correlate lots of stuff submitted
by many readers of this newsgroup.  This has been a very educational
experience, but now I need to get back to the real world.

Also remember that scale is the ratio between the size of the model and
the size of the prototype.  Gauge is the distance between the outside
rails.  Standard gauge in the United States is 4'8.5".

The first scales were numbered.  #1 scale and "O" (zero) scale are still
common; the larger #2 and #3 scales are rare.

Many scales also have narrow-gauge modeling specialties which use smaller
prototypes and more diminutive track.  Some narrow-gaugers use standard-
gauge track from a smaller scale (e.g., Nn3 uses Z, HoE and HOn2.5 use N),
ignoring small gauge inaccuracies and incorrect tie proportions.

NAME SCALE   OTHER INFORMATION
---- ------  -----------------------------------------------------------

Larger scales used in  Live Steam railroading:
     1:2.4   5" = 1'    24" gauge; live steam railroading in parks and
                        commercial

     1:3     4" = 1'    18" & 19" gauge; live steam railroading in parks
                        and commercial; mining equipment was 18"

     1:4     3" = 1'    15" gauge (twice as big as 7-1/2"); live steam
                        railroading in parks

     1:4.8   2.5" = 1'  7-1/2" gauge; 3' Narrow gauge for 7-1/2"; live
                        steam railroading in parks

     1:7.5   1.6" = 1'  7-1/2" gauge; live steam railroading in parks

     1:8     1.5" = 1'; 7-1/2" or 7-1/4" gauge (7-1/2" most used in USA)
                        A common size for outdoor models used in some
                        amusement parks and museums to carry people.

     1:9.6   1.25" = 1' live steam railroading in parks

     1:12    1" = 1'    4-3/4" (4-1/2"?  I'm not sure about gauge)

     1:16    3/4" = 1'  3-3/4" (Again, I'm not sure about gauge)

     1:20    A triple-threat scale:
              1. "American" G scale for purists modeling 3-foot gauge
                 western prototypes.  Rarely used in mass-produced models.
              2. this is #2 scale for standard-gauge models running of
                 2.75" gauge track.  Strictly for hard-core modelers
                 from scratch.
              3. A longtime favorite scale for non-railroad scale
                 modelers: auto, truck, ship, plane, diorama.

G    1:22.5  or 1:24, or whatever the manufacturer decides!  G = "Gross"
             (as in "big"); popularized by LGB; larger than O; has several
             different proportional scales from which to choose.
             #1 track works out as European metre-gauge in this scale.  
             LGB:  Lehmann Garten-Bahn or Lehmann Gross-Bahn
                  (??? someone else wrote "G stands for Garten, the
                   German equivalent of the English word "garden")

     1:24    1/2" = 1'  a variant of G scale used for 10% compression of
             larger models.  Wheel gauge is kept same as #1.

     1:29    a compromise scale for building standard-gauge trains for G
             track that can sorta inter-operate with G scale.
             1:29 models are almost always foreshortened.

#1   1:32    1cm = 1'  The "big one" from Maerklin; for scale modeling
             of standard-gauge trains on G (LGB) track.  Favored for
             hard-core collectors of extremely large train models.
             Its big advantage is it's big enough to model live steam.
             #1 gauge has been reborn as G (see earlier).

O    1:48    1/4"  = 1', or 7mm = 1'.  Although often called "oh" scale,
             "oh" stands for the number zero, not the letter after "n"
             in the alphabet; the scale is actually "zero" or "nought"
             (or "naught").  This is the model gauge smaller than 1 (one)
             gauge.  For historical reasons the track is laid to 5' gauge
             instead of standard.  Thus, O scalers divide into several
             camps:
              1. Mainstreamers ignore the gauge discrepancy
              2. "Q scale" uses a closer spacing of the rails (1 1/8"),
                 but it uses the same track/wheel standards as 0 scale.
              3. "Proto:48" uses a track gauge different from Q, and, in
                 addition, the wheels and flangeways have very different
                 standards much closer to actual scale.
              4. A very small group models at something near 1/45 to get
                 everything back in scale while allowing mechanical
                 interoperation with the mainstreamers.
              5. Another 0-gauge scale is 17/64".  At one time, buyers
                 had a choice of getting 0-scale models built to either
                 1/4" or 17/64" to run on the same track.
              6. 0 "tinplate" or "hi-rail" standard based on old toy
                 train dimensions.  For more on "tinplate", see near
                 the very bottom.

             One thing several contributors noted is that all of these are
             mutually NON-interoperable. They share a common size of the
             models, but they are really different for model building,
             layout building, and purchasing points of view.
             
             Someone noted that O scale is 3 rail Lionel, while there
             is an old scale referred to as 1:48 scale that is 2 rail.
             But someone else vehemently (with lots of !!'s) noted that
             0-scale is NOT 3 rail Lionel!  With exceptions that can 
             be counted on one hand, nothing Lionel made can be considered
             as 0-scale. 0-SCALE has implications of wheel/track geometry
             that are very different from Lionel toys.  Most Lionel trains
             are made to a "rubber" scale that varies from 3/64 - 1/4".

             For more on Lionel and O gauge, see near the very bottom.

O-27         The designator after the 0 refers to the diameter of a circle
             formed by the toy track. 0-27 track manufactured by Lionel
             (and others) also happens to have a lower profile, but that
             is incidental to the meaning of the term.  Other such
             designators commonly seen include 0-36, 0-42, and 0-72.  This
             is really not a gauge/scale but just a variation in 0-gauge
             fixed-radius toy track as provided by commercial sellers.

S     1:64   3/16" = 1'  A common building architect's scale.  Originally
             called CD, but changed to S to reflect its actual scale
             (one-Sixty-fourth scale.)  Much "scratch-built" stuff uses
             this scale.  The "up and coming" scale (same scale as most
             Ertl toys, more things being made at affordable prices, etc.
             American Flyer Tin Plate was close to S, and, except for the
             wheel flanges, was generally very close to scale.)  There is
             also an alternative "tinplate" or "hi-rail" standard for S.
             For more on "tinplate", see near the very bottom.


009   1:72   4mm = 1' scale, with 9mm gauge.  Many locomotives and rolling
             stock available as kits, and with an 8-inch minimum curve
             radius one can fit a fun layout into a space 2ft (60 cm)
             square.  The scale is big enough to scratch-build and to
             detail very effectively; because prototypes such as the
             Ffestiniog Railway and the Vale of Rheidol Railway in Wales
             run through spectacular scenery, ones imagination can run
             riot as one does cliffs, gradients and bridges. 

OO UK 1:76   4mm = 1'  The gauge is the same as HO: 16.5 mm.  This is the
             predominant "Toy Trains" scale in the UK, and other
             (ex-British) Commonwealth countries, with a number of
             manufacturers still producing--e.g., Hornby, Lima, etc.

00 US 1:76   5/32" = 1', with a gauge of 3/4".  00 US had a good commer-
             cial foothold in the US until the war interrupted "toy"
             (non-essential) manufacturing.  After the war, H0 gained in
             popularity in the US, and 00 almost totally passed away.
             There are, however, still several 00 layouts in operation
             in the US.

             When HO scale was first developed, models of British loco-
             motives were too small to fit around the electric motors of
             the day, so Hornby  developed a scale they called Double-O
             (OO) which ran on a three rail electrical system. Triang
             Hornby then introduced a two rail pick up system, using the
             same track standards (approximately) as HO (at the time).
             One can model the Glasgow Subway in it (4ft 0in gauge).

OO9   1:76   UK Narrow gauge; 9mm track gauge.

EM    1:76   4mm = 1'  UK, originally 18mm gauge, now 18.2mm gauge.
             First attempt at fine-scale started in 1950's.  There
             are some parts for re-wheeling commercial items to
             this gauge, and numerous kits. Track is now available
             from a few sources and maybe more gauges.

P4    1:76   UK very fine scale, track gauge 18.83mm.  "True" fine-scale
             started in late '60s.  Mostly Scratch.  There are other
             4mm/ft camps in the UK:  P4 and S4 are now a fairly unified
             camp of fine scale modelers who had a series of acrimonious
             rows in the late 1970's. The approach is (almost) no
             compromise prototype accuracy, and a track gauge of 18.83 mm
             is used.  Most P4 models tend to be of smaller rural
             prototypes, though there have been some larger models.
             Similar supply of parts to EM. Tendency to build locos with
             fully sprung or compensated mechanisms, and coreless motors
             (usually Portescap).

HO    1:87   3.5mm = 1'   "Half O scale"
HOn2         running on narrow gauge rails spaced  2  (scale) feet apart
HOn2 1/2     runs on the same gauge track as N; those modeling the Maine
                  narrow gauge lines use this scale. 
HOn3         running on narrow gauge rails spaced  3  (scale) feet apart
HOn3 1/2     running on narrow gauge rails spaced 3.5 (scale) feet apart
HOnm [meter]
HOe           9mm track gauge?  Also called HO9?
HOm          12mm track gauge?

TT    1:102  Also known as "table-top" ("TableTop" was used in publicity).
             It was produced by Triang/Rovex in the 1960s to 3mm scale.
             Commercial production then ceased but use of the scale
             continued with little commercial support, under the title
             "3mm scale", to mostly fine-scale standards.  There is a 3mm 
             Scale Society in Britain.  It never really caught on in
             America.

n     1:128  3/32" = 1'

OOO   1:152  Now obsolete, UK attempt at commercial models in mid 1960s.
             A few collectors items still around. Succeeded by N
             commercially.  Around the mid-50's on the European
             continent Kersten made 000 8mm track; it was not a success.

N     1:160  "N"ine (9) millimeter gauge,
             except 2mm = 1' in some UK modeling
Nn3          running on narrow gauge rails spaced ? (scale) ? apart

Z     1:220  Maerklin (spelling?) Mini Club, mostly a collector's scale
             and quite expensive.  Marklin is the main player, but
             MicroTrains makes better looking US prototypes.  Z was
             chosen because it is the last letter of the alphabet and
             was considered appropriate for the size, since there will
             probably never be any trains made in a scale smaller than Z.

???   1:400  Someone said that trains in this scale were driven by small
             jets of air between the rails.  Has anyone else heard of
             such a thing, or is it just a one-time-only thing?


MORE ON LIONEL AND O GAUGE:
--------------------------
First, it is necessary to keep the distinction between "gauge" and "scale"
in mind at all times to avoid confusion.

Lionel (and other toy trains) ARE 0-gauge, meaning they operate on track
that has a nominal 1 1/4" distance between running rails.  That is why
they are called 0-gauge.

However, the actual trains are not necessarily, in fact seldom, made to
"scale". Rather, they are made to some size smaller than actual 0-scale
because of the need to conform to manufacturing considerations, cost
considerations, and the need to allow for over-size flanges and very
sharp curves.

The use of the term "scale" implies that the entire model is made with
few compromises in proportion, ideally none.  Entire layouts are built
by "0-scalers" (of whom I am one) which have track made of two rails and
switches, etc., very close to the proportions of real track. The rail
has a flat head, not the circular head of toy track. The rolling stock
for such layouts has narrow wheels and small flanges (compared to Lionel
trains, eg), although not as finely proportioned as Proto:48, say.

The use of the word "scale" in regard to [Lionel] toy trains is thus
inappropriate for two reasons:
  1) the scale, if any, of a toy train is usually not the appropriate
     1/48, and
  2) the word "scale" has a jargon meaning, if you will, with strong
     implications about the sort of track and wheels standards in use.

In the more well-known area of H0, toy and scale standards are much closer,
and the distinction is not often made. H0 toy trains, such as Tyco, use
flat-headed rail for instance, and toy and scale trains are inter-operable.
Persons used to the vague difference between "gauge" and "scale" in the H0
world are often taken aback by the sharp distinction drawn by the 0-scale
world.

The history of the development of model railroading is an interesting one,
and much of this question relates to the growth of the scale model rail-
roading hobby out of the early toy trains manufactured in Europe even
prior to 1900 where the various gauge designations first arose (#3, #2,
#1, #0, #00, etc.) What seems capricious or arbitrary is the result of
historical accident.


WHAT IS "TINPLATE"?
------------------
The very earliest toy trains were often made of cast iron.  Starting about
the turn of the century, the toy trains began to be made of sheet metal,
tin-plated for rust-resistance. Such trains were usually beautifully (even
by today's standards) lithographed for color, lettering, and small detail.
Later, toy trains began to be made of various ferrous and zinc castings
and still later of various plastic materials. Through all this, the track
sections sold with the toy trains were made of 'tinplate' rolled/folded
into a sort of rail shape.

This long-term association of tin-plated material led to the use of the
term "tinplate" to refer to toy trains. The term is used to refer even to
such Lionel trains that are made exclusively of plastic and metal castings.
It is the term often employed to distinguish the 'scale' trains from the
'toy' trains.  Since 'toy' might be taken as a pejorative term, most
people are happy with this use of 'tinplate'.

Other examples of 'tinplate' include Gilbert (American Flyer) in S gauge,
HObbyline in H0, MarX and Hafner in 0 gauge, Lionel in 00 gauge (pre-war),
Ives/Lionel/American Flyer in Standard gauge, Maerklin in H0, and on and
on. 000 was primarily a tinplate gauge as the models and track offered
were to very coarse standards.

Lionel did make a few scale models just prior to the war, e.g., the NYC
Hudson which was designed for, and sold to, scale hobbyists.  They have
recently began offering a few scale models again, e.g. the Dreyfuss Hudson.


Thanks, everyone.
--Myron.
-- 
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