Why is called HO?


Salv 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 :) Beowulf
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Beowulf wrote:

HO is only 3.5mm : 1 foot in Britain only - the rest of the world uses slightly more sane scale ratios because we all gave up archaic measuring systems based on barleycorns decades ago.
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Greg Procter wrote:

Are you sure Greg?????
Chuck D.
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Charles Davis wrote:

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) =8^)
Regards, Greg.P.
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Greg Procter wrote:

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 spindly)
Chuck D.
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Charles Davis wrote:

The NMRA standard for HO is _not_ 3.5mm:1 foot, it is 1:87.1 which is different.
Quote from previous posting "> > (the US is a wrong answer) =8^) "
Regards, Greg.P.
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Greg Procter wrote:

snip
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 measurement conversions.
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 inch/thousandths).
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!
Chuck D.
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Charles Davis wrote:

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.
Regards, Greg.P.
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Greg Procter wrote:

Who says I don't?? They are advisory, not mandatory!!!

Nope!! 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 challenged.

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.]
Chuck D.

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Salv
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! Beowulf
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Beowulf wrote:

I'm a scratch-builder, I'm well aware of compromises being neccessary. =8^)

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 them. 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.
Regards, Greg.P.
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just
Rocket"
back
do
rest
that
guineas
standardised
Salv 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
Beowulf
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Beowulf wrote:

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 Whangarei.
Regards, Greg.P.
Regards, Greg.P.
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"> > As

been
beyond
I endevour to keep my hobby and my profession seperate though they both delight me :) though not necessarilly anyone elese :)

even
Brunswick
a
superb
with
alight
eggs
beautful
Only if someone slaps you about the face with one :)

yes
carpet
to
few
then
wee
you
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 :))))) Beowulf Beowulf
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Beowulf wrote:
<snip>

Hey, I'm older than they are!
Like me they are over twenty years old with long wheelbase, but had a speed limit rating below that of current mainline trains.
, I still havent gotten over a

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Greg Procter wrote:

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.
Terry Flynn
http://angelfire.com/clone/rail/index.html
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
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NSWGR wrote:

Make that less than 1% difference. or slightly more than 0.1% difference!
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 be 1:87. You're not arguing _my_ distinctions, you're arguing against MOROP, Henry Greenly and the NMRA.
Regards, Greg.P.
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