Martin, I agree with almost everything you say, but you are talking about fine scale models. a/ This is not what has been offered in the HO RTR European market - their models have basically under width chassis frames, but the bodies have been roughly to 3.5mm scale width (I realise I am generalising here when there are literary hundreds of different models). b/ Why would European models not be the same as OO, i.e. 3.5mm chassis &
4mm bodies?
Well it is easier to move wheels out & build new track than do the reverse, i.e. narrow the bodies to fit the track. In fact there is a prototype for this which failed too. BRC&W tried it with the Class 33/2 diesels (Hastings loading gauge), it proved far harder to do this than anticipated and was a major factor in sending them broke.
They do indeed come up with a much better compromise than OO. You only need to glance at the Roco range for instance to find good quality models, or Proto 2000 for US models.
The only model that comes to mind of a British prototype modelled to a respectable version of HO is the PSM Flying Scotsman, but that was a very limited edition brass model. PSM originally planned to do a small collection of HO British, but the Scotsman was the only one produced. The fact that FS travelled to Australia & much earlier the US was probably the only reason that it was the guinea pig for an HO model.
That's true of course, and I wasn't suggesting otherwise.
I was referring only to r-t-r (ready-to-run commercial models), for which the standards are, or were originally, designed for the toy market.
For such models you can have a scale track gauge or a scale-width model, but you can't have both -- and that applies especially to British-outline steam locomotives.
00 r-t-r chooses a narrow track gauge, H0 r-t-r chooses over-wide models. The great advantage of the former is that for those who want to convert from a toy mechanism to something approaching scale running gear, the basic model is, or should be, correct to scale.
All OO models are also but with HO at least the gauge is correct.
Of course it is but then no one is suggesting otherwise. horses for courses, if you do not want to go overscale in the width then dead scale is the only way. Toys rather than models can have over scale flanges and over scale width, children are not going to complain.
Cobblers, see above.
Quite so but the thing that marks out a railway from other sorts of transport is two parallel strips of steel, in other words rails are fundemental so we should get them the right distance apart.
No you do not! If you want larger flanges then ease the check gauge through the points and alter the back to back of the wheels. Hornby could have made the gauge anything they liked as long as the standards were consistant.
Quite so but if the scale of the models had been 1:87 then the gauge would not have needed changing either.
I'm afraid that won't work. In order to run properly the flanges must be angled. That means that if you want them deeper than scale for reliable r-t-r tracking they must inevitably also be thicker.
Thicker flanges require wider flangeway gaps in the track. This means that the wheels must be wider than scale in order to span the gaps and be fully supported through crossings (frogs). Otherwise they will drop in the gap in front of the crossing vee.
Because there are two gap-widths there, the effect is magnified. The wheels must be widened by *double* the amount that the flangeway is widened in order for the wheels to be properly supported.
If you want the model to run properly there is no getting away from it -- if the flangeway is wider than scale, the dimension across the outer faces of the wheels must also be widened. Then the only way you can fit them within scale-width splashers, etc., is to close them back in by narrowing the track gauge.
Or you can choose instead to have an over-width model.
Ah, sorry, I thought we were having an intelligent discussion. I was warned once before not to try that on this newsgroup.
regards,
Martin.
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What I'm trying to say is that if the bodies of our trains had been made the same scale as the track gauge then life would have been easier. Its a hypothetical position as this did not happen. I've a huge interest in the history of model railways and the manufacturing techniques involved and idlely wonder what would have happened had other decisions been taken.
I model Irish narrow gauge in 15mm scale on 45mm gauge track so I suppose I should mind my own business really. :-)
That's ok. It's strange that this arcane subject gets us so heated!
One of the most interesting "what-if"s is what would have happened if Peco had proceeded with their plans for EM gauge track. It's known that they were working on it in the late 60s, but cancelled the project when the first magazine articles about P4 appeared. They reasoned that with both EM and P4 the market would be too fragmented to be profitable.
The result of that is that 40 years later they still do not produce any proper 4mm track, and the majority of 00 gauge models today are running on track that bears not the slightest resemblance in scale or detail to British railway track. I think it is this which makes folks so disparaging about 00 gauge, not the actual dimensional discrepancy in the distance between the rails.
In fact it is possible to build 00 gauge track using 4mm scale components which looks very much like the prototype, but pointwork is not available off the shelf, unfortunately. You could hardly mix C&L 00 flexitrack with Peco turnouts!
regards,
Martin.
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I'm not sure I would want off-the-shelf pointwork. Even I, with my limited skills, have managed to produce some decent looking 00 gauge turnouts using C&L components and Templot.
As was SMP Scaleway. It was also code 75 AFAIR, a lot finer than Peco.
There was a pre-streamline flex track with better sleeper spacing, Pecoway(?). But this was superceded when streamline was introduced "with the finescale longer look".
From most angles, overscale flanges are far more noticable than undergauge wheels.
During the period in question, mass-produced models wer not yet available in small scales. GEM made bespoke locomotives to special order in H0, 00 and
19mm. All three were made to exactly the same standard but in the opinion of George Mellor, his 00 models looked much more prototypical than either of the others two.
There is usually an exception to the rule. The RTR Eureka models H0 NSWGR AD60 now on the production line has scale width running gear and scale width outside cylinders. Using 2.2mm wide wheels is the answer and a check gauge less than scale. There were a number of RTR brass models on the Australian market which used 2.4mm wheels which also achieved scale width with outside cylinders and valve gear.
Now I thought you of all people would know the answer, which is around
16.1mm to 16.3mm for current H0 wheels. You don't notice the gauge difference in H0. From a historic view point H0 was originally defined as half 0 gauge = 5/8", 15.875mm.
I agree. Personally I consider 4mm / ft a better scale to work in compared to H0. Things are a bit bigger, easier to see and make models yet not to big as to make building indoor layouts to large. My H0 finescale wheel page also explains the wheel width issues. My wheel and track standard spread sheet includes comparisons with model wheel width and scale width.
Terry Flynn
formatting link
HO wagon weight and locomotive tractive effort estimates
The last I heard they were owned by The Train Shop in Warwick, but they ceased trading a long while ago. Not sure what the position is with regard to ownership of SMP these days.
Yes, but this discussion is about bog-standard H0 r-t-r.
2.2mm wheels won't run on such track. The gap across in front of the vee is 2.5mm wide, and a 2.2mm wheel is going to fall right in with a nasty bump.
In fact many 00 wheels are barely wide enough -- Romford/Markits are only .100" wide (2.54mm) and rely on using sharp-nosed vees to be fully supported, just. If prototypical blunt-nosed vees were used, the gap in front of them would be wider than .100"
The reason so many folks get bumpy running through crossings (frogs) is that they use wheels which simply aren't wide enough -- can anyone remember PC Models 00 wagon wheels? These new models you refer to look like making the same mistake.
Obviously if you build your own track you can reduce the flangeways (I won't mention 00-SF yet again ) and use narrower wheels. But then we are no longer talking about commercial r-t-r.
Yes, but as I said this discussion is about commercial r-t-r, i.e. standards which were devised for TOYS. You need to allow for increased sideplay, oversize coupling rods and crankpins, make an allowance for moulding thickness and tool draw angles inside splashers, etc.
00 gauge does all that for 4mm scale. By using a reduced gauge you can have a scale width model and still fit a commercial mechanism inside it. A gauge of around 15mm would have done the same for
3.5mm/ft scale.
I'm not seriously suggesting that -- nothing is going to change now. Just trying to open the eyes of those who think the track gauge is the be all and end all, and that H0 would be the answer.
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