It's called HO or Half O because A.R. Walkley who invented the scale
(Before Bing!) called it HO and the name has since then stuck, because of
the strictures of creating small electric motors the rest of Britain
enlarged it to OO so as to use the smallest economical electrical motors
then available, it remains the most popular "scale" in the UK, HO is 3,5mm
to the foot and 00 is 4 mm to the foot. (just to make things easier 8) )
A.R.Walkley made everything himself including the motors something whixch
thankfully we dont need to do today :)
Can you think of anywhere else generally using 3.5mm:1foot, other than a
few odd people outside the UK (add in the IOW and Channel Islands pop
and prototypes) who model British prototypes?
(the US is a wrong answer)
Well Greg, you obviously DON'T know about the U.S. of A. (North America)
3.5mm = 1' is what I've been using for over 50 years, Including making
'masters' for 'lost wax casting', cutting SCALE lumber (2x4s are real
Who said anything about the NMRA????
You sound like you are an incarnation of "Terry Flynn"
I said "I use 3.5mm = 1'", including all the mathematics for the
And so do 'most if not all' of the other folks around here.
Actually, it ain't all that hard to do. PFM (Pacific Fast Mail) had a
vernier caliper available with "HO" calibration (as well as
What most of your arguments boil down to, is similar to the story of the
man talking to St. Peter (at the Pearly Gates) about how he got there,
and explaining that because the "Red Light" wasn't the proper color, he
was darned if HE was going to stop!
Why would you not use the standards of your national body?
Are you about to spring it on me that you're NOT from the USa?
I don't do my HO modelling in feet and inches so such a vernier caliper
would only be an annoyance to me.
Not at all - I pointed out that most prototype dimensions on rolling
stock built to Imperial measurements have three units requiring
individual conversions and which then need adding together, while
metrics have just one - that's four chances of error _before_ one
converts to a scale dimension After conversion the luckless Imperial
modeller needs to convert his new number into (at least) two, being
inches and fractions of inches.
After all that we have materials produced in at least three differing
measuring systems to combine into a model.
Put simply, archaic Imperial measures are a pain in the .... and it's a
long overdue move for the US to come into line with the civilized world.
Who says I don't?? They are advisory, not mandatory!!!
Started modeling while in California, Eventually moved to Virginia. The
"HO" seemed to me to be the same on both coasts. ;-)
Just pointing out the availability of 'helps' for the mathematiclly
In general, you are right. That said, this is a HOBBY, and those little
challenges are a part of what is there to be enjoyed as a challenge, or
ignored to whatever extent the individual 'Hobbiest' desires.
and it's a
[Right!! and mandate ENGLISH for language, the Latin alphabet, Arabic
numbering, etc. Yeah,, good luck on trying to get that to happen.]
The problem is Greg that for modellers any reduction for scale purposes is
going to be a compromise, because a reduction will have to by necessity
compromise in certain areas, ie if the original object to be reduced is in
certain areas measured in thou (imperial inches) are you going to try to
modell that part to its scale equivalent... not unless you are extremely
wealthy no one will reduce it to a millionth of an inch +/- 20 mill just
for accuracies sake especially when like early locos such as "The Rocket"
tolerances were measured in inches (piston slap really meant something back
then!) so for my part if it looks right then it is right, paints never do
accurately reproduce the real thing in scale just approximate but the rest
of us that enjoy models , be they planes or boats or trains are happy that
they do an HONEST job as far as is reasonably possible.
Being British I was brought up on truly archaic measurement rods and
perches etc not to mention the delights of 240 penny's to a pound not to
mention 480 halfpennies 80 threpences, 40 sixpences, 20 shillings , 10
florins, 8 halfcrowns , 4 crowns , 2 tenshilling notes and golden guineas
and if I'd been born a year earlier 960 farthings or even earlier 1920
groats toa pound, so I can appreciate the problem which you apparently are
not taking as serriously as the British who for many years delayed the
introduction of the metric system in the UK untli the EU had standardised
upon a SINGLE (there were at least three!) metric system, and that only
happened a couple of years ago!
I'm a scratch-builder, I'm well aware of compromises being neccessary.
I'm in full agreement so far.
A point I'm trying to get across is that the time to make such
compromises is when the execution of precise scale proves to be
impractical, rather than before even deciding how the initial
measurements will be scaled.
Obviously this isn't something that concerns those modellers who buy
their models off the shelf as all the compromises are already made for
Paints/colour is a whole new discussion and one that can never fully be
resolved for a whole raft of reasons.
I also was brought up with those same dimensional and monetry systems.
That's a wonderful excuse, but the precise definition of the metric
system is a 'red herring' as it has been more accurately defined than
the imperial system for the best part of a century.
Actually Greg you are wrong here, the standards in question are not those
of measurement in the linear sense of how long, but in the engineering
sense of what angle a screw thread was to be and so on, these were not stan
dard throughout europe, in fact some of the Imperial standards exceed those
of the various continental systems cycle threads come immediately to mind,
Royce Creasey the engineer used to wax lyrical on these standards some
twenty years ago in Classical mechanics (classic ´motorycycles mechanics
that is...) and until these standards were unified legal cases throughout
the common market (EU now) could not be rectified in the customers or
manufacturers favour...or otherwise because each nation had its own
standards and those of other nations not sharing its standards were by
default as it were..illegal....and in the case of an accident who was to be
held to book? Britain wisely waited with its ancient system until such
standards were unified throughout a now semi united Europe, now its caught
up with the rest of Western Europe faster than they expected :) USA
manufacturers often work to moden metric standards and in scientific
practices nearly always work to metric standards so its only a matter of
time before the USA also goes the way of post napoleonic metrification :) As
far as the Imperial system is concerned the various measurements have been
for the better part of a century been standardised on various isotope
wavelenghts just as the metric system is, how this came about is far beyond
my ken as my area of expertise is Radical Contextualist Theology and not how
to decide which wavelenght of which isotope to use for what prpose,
personally I think that channels like this one are not to be used for
personal abuse, but for chatting about railways :) of all types from the
neolithic ones of Malta to those of the United Kingdom and the americas even
those breakaway colonies (so sad !) both north and south of Panama :))
Personally I think that Great Western steam loco's resplendant in Brunswick
green and gleaming polished brass steam domes and chimney's topped with a
polished bronze "cap" like a wonderful Edwardian metal top hat are superb
and Gresleys, LNER fully lined out varnished teak carriages along with with
Staniers LMS carriages for sheer comfort and the wonderful smell of a
Manchester Pullman pulling into Watford Junction at 08:20 am each door
resplendant with fully liveried waiter awaiting to help passengers alight
and board, yes the memory of the wafting wonderfull scents of bacon and eggs
andManx kippers and smell of luxury coffee that wafted out of those beautful
carriages (now used on the orient express :(.........) made my day when I
was training as a train Guard and doubled up as a railwayman ( a railway
servant to be exact , porters had ceased to exist some 20 years earlier) yes
and that was in the late 70`s (1979 not 1879!) now you have to pay a carpet
(£500) or so just to experienc half the service on a fake Orient express
:( Its no wonder that we like to model trains :)So lets stick to trains and
not to the sexual habits of sheep no matter how attractive they may be to
australians in their fantasies about NZ, personally I'd like to here a few
more experiences here by folk who actually worked on railways , both then
and now , this makes a model railway really come alive knowing that a wee
bit of it isnt as passengers remember it but as the railway servants or
workers or footplatemen remembe it. Any other ideas about this folk...if you
havent already killfiled this thread :D
I'll accept that - however my HO models generally don't go as far as
representing scale screw threads and on my my G24 garden models I
deliberately don't thread the exposed screw and rodding so as to better
deal with the rough and tumble of outdoor usage.
Perhaps you don't remember just how many different thread standards
there were under the Imperial systems? Every industry had it's own
unique standards, often several on any given product. One couldn't buy a
replacement bolt from an engineering shop but rather had to go to the
local representative of the particular manufacturer (if such still
existed) who hopefully would have reference material as to what
particular standard bolt was used in a 1951 Jowett Javellin gearbox
speedometer drive union.
Systems - lots of them!
I'm waiting - meanwhile almost anything I want to buy from there is
having it's production transfered to China.
I'll remember not to expound my various unfounded nonradical theories to
you on this ng!
I 've never smelled a Manx kipper - does the lack of tail and the three
legs alter the aroma noticably?
That sum would almost buy you a model!
I never worked on the railway but I did load/unload a wide variety of
goods wagons in my student days - the louvered vents on the X class van
ventilators gave one a view which allowed 2-3 seconds of warning of the
boss's silent arrival to check on we slackers!
Outside my computer room window is the local branchline - several times
per day a train rumbles past, either L wagons (the last 4 wheelers in
use in NZ) modified for circa 3m small logs or U wagons with fittings
for larger logs, all pulled by whatever loco is currently spare in
I endevour to keep my hobby and my profession seperate though they both
delight me :) though not necessarilly anyone elese :)
Only if someone slaps you about the face with one :)
Its always fun to see ancient rolling stock , I still havent gotten over a
trip in Finland when the conductor/Guard (I'm not sure of the difference I
was a Guard not a conductor ...they were found on buses and didnt need to be
able to read.......) who kept walking past me with armfulls of
logs...finally I asked him why, he then showed me the log burning stove in
the carriage , I thought it smelled nice :) Train services in other
countries also had their delights like travelling in immediately post soviet
Estonia and not being allowed to draw the curtains on the window to see
out... but being served a piping hot cup of russian tea on a little tray
built into the arm rest of the chair, an amasingly comfortable trip, after
all the propoganda I'd assumed that they were still using planet type
locosand was suprised to see what looked like angular versions of RS3's at
the port side... I believe you are now allowed to look out of the windows
without facing a firing squad :)))))
The difference in the NMRA 1:87.1 scale, the NEM and AMRA 1:87 scale
and the UK modellers definition of 3.5mm foot is only about 0.001%
difference. Less than the shrinkage in the materials used to make cast
models. A good example of maximum debate over irrelevant differences.
HO wagon weight and locomotive tractive effort estimates
DC control circuit diagrams
HO scale track and wheel standards
Any scale track standard and wheel spread sheet
Make that less than 1% difference. or slightly more than 0.1%
Less than the shrinkage in the materials used to make cast
If there was no relevant difference, why would different model
organisations bother to make the distinction?
MOROP's 1:87 is a whole number, whereas the NMRA felt the need to round
the UK standard 3.5mm:1 foot to get to 1:87.1
If those differences are irrelevant then why make them? All three would
You're not arguing _my_ distinctions, you're arguing against MOROP,
Henry Greenly and the NMRA.
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