Any suggestions for HO gradient?



You haven't put much thought into that statement, have you a_a_a? Your NMRA has put a lot of thought into creating a new standard over the existing International standard and has decided that that .1 is sufficiently important to outweigh the existing international standard.

LOL. The only thought you've had is to attempt to rubbish my thoughtful comments.
Regards, Greg.P.
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Greg.Procter wrote:

It's far more likely that someone mindlessly used a calculator and wrote down what it said, in the same mindless way that people convert integer mileages (rounded to the nearest half mile) into apparently precise numbers of single metres.

I rest my case, since you self-identify what you consider "thoughtful" comments.
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That's basically what happened. When the weathermen in my locality report record temperatures prior to metrication, they always add a decimal and is something they don't normally do.
In metric, measurements could be standardized as follows:
G - 1:25 O - 1:50 HO - 1:100 N - 1:150 or 1:200
Personally, I think it's a simple method, but defacto standards will prevail. Using a GE 70 ton unit measuring a 37' length as an example:
Prototype: 11,278mm G: 451mm O: 226mm HO: 113mm N: 75mm or 56mm
Likewise, Standard Gauge track at 56.5 inches becomes:
Prototype: 1435mm G: 57mm O: 29mm HO: 14mm N: 10mm or 7mm
The above measurements involve decimal places which are rounded off to the nearest whole number.
Cheers, John
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wrote:

Most of those scales have already been tried, for example "C" scale in the 1960s. Unfortunately people generally start in the hobby with whatever they can readily buy, so whatever already exists is what they continue with. 1:100 scale on 14.35mm gauge isn't intrinsically better than 1:87 scale and 16.5mm guage, or any other combination when one is buying off the shelf. For that matter, 1:87 is no better than 1:87.1 or 3.5mm:304.8mm if you're just buying off the shelf, as David obviously does. There are only problems when either one attempts to mix models built to different standards or when one needs to or attempts to build scale models.
Greg.P.
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On 3/1/2009 7:27 AM John Fraser spake thus:

Whoa: where do you get that last one? Rounding 1:87 to 1:100 is sheer sloppiness.
Oh, you're describing the theoretical proposed Perfect Metric version of HO, which doesn't exist.
O scale *might* be tolerably close (1:48 compared to 1:50 is close enough for many folks).
--
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David Nebenzahl wrote:

1:50 is to far from 1:45 which is the correct scale for standard 32 mm gauge track.
That 1:48 scale you mention must be invented by someone who couldn't do simple calculations.
--
Venlig hilsen/Best regards
Erik Olsen
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On 3/2/2009 9:35 AM Erik Olsen spake thus:

I have no idea of the arithmetic capabilities of whoever "invented" 1:48, but it happens to be the standard definition of O scale hereabouts. Don't look at me; I had nothing to do with it. Just reporting the news.
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David Nebenzahl wrote:

Weird. Broad gauge; the opposite of British 00.
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Venlig hilsen/Best regards
Erik Olsen
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Erik Olsen wrote:

1/4" to the foot. Easy to measure with a dimestore ruler. ;-)
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Just like 1:87.1! (If your dimestore happens to have a 1:87.1 scale)
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On 3/2/2009 1:36 PM Erik Olsen spake thus:

O *scale*, not gauge. Dunno about the gauge; others will have to comment on that. Don't think it's broad gauge, though.
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David Nebenzahl wrote:

It's not that hard ----- 1/4" = 1 ' [the ratio IS 1:48] The 1'4" is for convinence for those without the equipment to work with the 7mm : 1' that the British folk use.
Chuck D.
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1/4" is 6.35mm, almost 10% out from 7mm:1'. Way back when (European) manufacturers used a variety of scales I considered 5% scale variation between models to be unacceptable.
Greg.P.
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Greg.Procter wrote:

You miss, or purposefully ignoring the point. 1/4" is a convenient dimension for those with 'normal' [read commonly available] rulers.
It's 'Close Enough' for the majority of folk. [Remember, back then it was not uncommon for "O" to be three rail, using an 'outside third rail' also, another GLARING departure from reality in most cases.]
Chuck D.
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Hi Chuck, the myth I was attempting to debunk there was that 1/4":1' followed from 7mm:1' as used in the UK. It followed from the gauge, the US citizens who founded it didn't look at what was being done by scale modellers in Britain, compare 7mm on their old school rulers with their brother's old school ruler inch fraction scale and say "1/4" is near enough to 7mm". More likely they measured the toy track gauge and decided 1/4" : 1' was close enough for their purposes. For goodness sake, give yank modellers of the past some credit!
Regards, Greg.P.
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Those old guiys were so bad at things that they considered that the track gauge was a scale 5'! Rather than change the gauge or the scale of the tinplate track, they just used the combination as it was. There are a lot of this kind of problems all through the S3 standard and nobody has any intention of changing any of them. Those taht are doing superscale stuff have done a fair bit towards making the wheel and track standards close to what the prototype is as well as following the basic form of the prototype design.
-- Bob May
rmay at nethere.com http: slash /nav.to slash bobmay http: slash /bobmay dot astronomy.net
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David Nebenzahl wrote:

In the US (NMRA S-3.2) the gauge is 1.250in (31.75mm), in Europe 32 mm.
For 1:48 scale, 1435:48 = 29.90mm or 1.177in would be appropriate.
--
Venlig hilsen/Best regards
Erik Olsen
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On 3/3/2009 10:34 AM Erik Olsen spake thus:

>

Well, whaddya know, that *is* broad gauge (exactly 5'). Hmmm. So now I have yet another reason not to ever use O scale (unless my eyesight gets really, really bad *and* I stumble into a boatload of money).

It's about 6% oversize.
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Erik Olsen wrote:

Look further, you'll find that the gauge min/max includes 32.0mm.

There were some modellers in the USA/Canada who adopted this gauge for 1:48 scale. Probably still are. Then there was Q scale, with a gauge of 1.1875" (pretty close to 1.177, you see....) More common was 17/64ths scale, for which 1.250" gauge was within 0.0006" of true value. There were probably more variations of sclae/gaiuge for "O" than for any other. The most common European scales were/are 1:43 (or 1:43.5 for the purists), and 1:45. In the UK 7mm = 1ft scale was/is used, which is 1:43.5 Hence 1:87 for "half 0". And so on.
It's all rather confusing, really. ;-)
For more see:
http://members.shaw.ca/twofooter/scale%20gauge.htm
It has a few typos, and some out dated information, but is generally accurate AFAIK.
cheers,
wolf k.
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Try calculating a prototype dimension like 3' 1 7/8" to modelling size in 17/64ths scale without a calculator! You'll soon understand why model dimensions were guessed at. You've even changed measuring systems to thou's of an inch to express the error!
16.5mm gauge is not half of 32mm gauge!
Greg.P.
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