1/120th Scale

[AndyID]

Hi Andy,

Thanks for your comments, you do make some good points, I don't deny that.

Actually, I was quoting Simon Kohler!

I do model 18.83mm gauge P4 from time to time, I have even tried P87 too but I'm one of those who likes to chop and change all the time, therefore I simply don't have enough time to convert all my stock, I'd need several lifetimes to manage that and I'm over half way through this one now.

I take your point about 1/82 scale or thereabouts, isn't that the Japanese version of H0 and what Fleischmann and Rivarossi used to work in?

I will open a new thread on the merits and demerits of H0 scale in due course, just a bit busy at the moment. If you'd like to preempt me, that's fine with me!

Cheers,

John.

 

Hi John,

 

I thought about another thread, but I'm not going to do it. I would if people could have a dispassionate and rational conversation about it, but I'm afraid it would only attract a bunch of hotheads and the discussion would spiral downwards into a slanging match followed by a bar brawl

 

Andy

[AndyID]

Thanks for pointing out that H0 is compromised too, just in a different place to 00.

So, considering the three recent threads about 1:100 and 1:120 would it be fair to sum up

- 1:100 (or 3mm) on 12mm is compromised like 00 in track gauge.

- 1:120 on 12mm or 1:100 on 14.2mm or so, would be compromised like H0 in cylinders etc (if it got used for steam and didn't remain a very modern prototype scale only) - unless the wheel standards were made a good deal finer than usual commercial ones (3mmFS equivalent, even P4 equivalent - ie near scale width) which would limit curvature etc.?

 

Hi John,

 

I have not done the arithmetic, but I think that's about right.

 

Again, I have not done me sums here, but I imagine that if we were allowed a "do over" of 00 from the start, it would now be possible to widen out the gauge a bit because of finer manufacturing tolerances etc. Not sure what that would mean of course. I hope nobody thinks I'm proposing such a thing for 00, but if a new scale/gauge were proposed for "TT" the acceptable manufacturing tolerances should be factored in determining the over-arching dimensions of the track and equipment.

 

I would think that could be a fairly time-consuming activity and there could be many heated debates before it's all ironed out.

 

Cheers!

Andy

[AndyID]

The ratio between HO and OO is 1:1.45.

 

Hi Nigel,

 

I'm not sure how you arrived at that ratio. I believe 00 is 1.14 times H0, which is 0.88 times 00

 

Andy

[Hobby]

 

In the case of H0 the compromise is that all the running gear has to be widened to accommodate the unavoidable wider treads and deeper flanges.

 

 

I though the reason behind OO was motor size rather than wheel treads, same as TT3... However much you comment on the wider bogie sides or valve gear, etc., on HO models I still find them much more acceptable than running 4mm scale models on 4ft 1in gauge track. These days it is possible to make the differences so fine as not to matter very much, if at all. Hence I feel that British 1:120 on 12mm track would be perfectly acceptable and a much better compromise than 1:100 on 12mm track. I do feel that you over exaggerate the compromises that HO modellers (and Continental TT ones for that matter) have to accept which are much, much less than those that OO modellers accept on a daily basis when using 16.5mm gauge track.

 

 

As for ebay.de, I wanted to pull some stats from somewhere - it seemed an easy starting point. I too was surprised that TT didn't rate higher, in the future I may attempt to discover more reliable stats.

Cheers,

John.

 

Hi John, I can see your point, it's very difficult to find some way of doing useful comparisons I agree! Another possible (though more anecdotal) is by comparing the stock of Model railway Shops in various parts of Germany. I've lost count of the number of times that, having asked for TT stock, being told that I am too far West when I am in Germany. If you go to shops in the old West Germany they are mainly HO and N with some Z and very little (if any) TT, go to the old East Germany and TT is often on a par with N! If you shop in the Czech and Slovak shops it's mainly HO and TT level pegging with N way behind! Just shows where TT is still strong... There are some lovely TT SG models in the Czech Republic as well!!

[Revolution Mike]

Hobby

 

I can't help but agree with you that any compromises on HO (or TT120) stock are much more appealing than using OO and 16.5mm track.

 

The beauty of starting a new range (which this would effectively be) is that you don't have to pander to the problems of the past!

 

Cheers, Mike

[Hobby]

 

The beauty of starting a new range (which this would effectively be) is that you don't have to pander to the problems of the past!

 

 

Agreed, as are most people I think... The only question is whether is viable, SK and Forester seem to think it is, I'm not so sure myself, though I do think it would make a nice scale/gauge for British modellers if my experience of 1:120 is anything to go by!

[roundhouse]

We have in the past obtained some very nice resin body hand built Czech locos with scratch built chassis in TT. Also full working lights firm handrails etc. It just shows what's achievable in this scale as the detail can still be added as per HO but you can get a lot more in the space.

 

More recently companies such as Roco, Tillig, Piko and MTB make some superb TT ready to run locos. The MTB even have built in speakers ready for fitting a 22 pin Plux decoder. Tilig TT scale track is also very good although sleeper spacing would be incorrect for British modellers but no worse than Peco.

 

It is a great scale to work in.

[NCB]

Hi Nigel,

 

I'm not sure how you arrived at that ratio. I believe 00 is 1.14 times H0, which is 0.88 times 00

 

Andy

Andy

 

Oops! Thanks for pointing that out; I dropped a 1 in both figures. It should read 00 is 1.145 times HO and 3mm is 1.186. I've corrected the post.

 

Cheers

Nigel

[NCB]

I though the reason behind OO was motor size rather than wheel treads, same as TT3... However much you comment on the wider bogie sides or valve gear, etc., on HO models I still find them much more acceptable than running 4mm scale models on 4ft 1in gauge track. These days it is possible to make the differences so fine as not to matter very much, if at all. Hence I feel that British 1:120 on 12mm track would be perfectly acceptable and a much better compromise than 1:100 on 12mm track. I do feel that you over exaggerate the compromises that HO modellers (and Continental TT ones for that matter) have to accept which are much, much less than those that OO modellers accept on a daily basis when using 16.5mm gauge track.

 

 

Hi John, I can see your point, it's very difficult to find some way of doing useful comparisons I agree! Another possible (though more anecdotal) is by comparing the stock of Model railway Shops in various parts of Germany. I've lost count of the number of times that, having asked for TT stock, being told that I am too far West when I am in Germany. If you go to shops in the old West Germany they are mainly HO and N with some Z and very little (if any) TT, go to the old East Germany and TT is often on a par with N! If you shop in the Czech and Slovak shops it's mainly HO and TT level pegging with N way behind! Just shows where TT is still strong... There are some lovely TT SG models in the Czech Republic as well!!

Hobby

 

The motor size thing with OO is a long standing and widely accepted myth. But definitely a myth. George Mellor who was involved in the original decision published an article giving the thinking behind it. The basic reason was trying to get wheels of the practical thickness inside British bodies. The "motors available at the time" didn't come into it; Hornby designed and made their own motors and could easily have made something to fit in an HO body.

 

Commercially the narrower track in OO doesn't seem to put anybody off, and some of the current offerings are superb. I find accurate bodies on narrower track much more acceptable than compromised bodies on dead scale track. And that's from somebody who models scale models on scale track. Maybe it's because I do that I can see why a commercial manufacturer wouldn't. For a start, in 3mm I work to a ruling minimum radius of 40", can take it down to 32" if really necessary, have one curve at 29" but that's really pushing it and involves gauge widening, and other complications. A manufacturer would want something like 16" curves or less to retain the "takes less space" advantage.

 

Cheers

Nigel

[Revolution Mike]

Commercially the narrower track in OO doesn't seem to put anybody off, and some of the current offerings are superb. I find accurate bodies on narrower track much more acceptable than compromised bodies on dead scale track.

 

OO it puts plenty of people off, but how do you quantify it! I suppose you could start by those who model in EM or 4mm. The reality is that it is a historical issue that there is no need to repeat - are you seriously saying that if 4mm scale was starting from scratch that the choice of track would by 16.5mm?

 

I don't think that anyone is talking about compromising the bodies - sure you would have to build in some looser tolerances (and perhaps compromise some under the footplate dimensions on steam locos) if you wanted very small curves.

 

Cheers, Mike

[AndyID]

OO it puts plenty of people off, but how do you quantify it! I suppose you could start by those who model in EM or 4mm. The reality is that it is a historical issue that there is no need to repeat - are you seriously saying that if 4mm scale was starting from scratch that the choice of track would by 16.5mm?

 

I don't think that anyone is talking about compromising the bodies - sure you would have to build in some looser tolerances (and perhaps compromise some under the footplate dimensions on steam locos) if you wanted very small curves.

 

Cheers, Mike

 

 

Hi Mike,

 

I don't think anyone is suggesting that 00 would have to be 16.5 mm gauge anymore, I certainly was not, but it could not be close to 18.8 mm without making some serious "adjustments" to bodywork and running gear. The same applies to any proposed or current TT scale.

 

To my knowledge there is no way to get around this, but I'd be very interested in seeing any drawings you might have that explain how it can be done.

 

Cheers!

Andy

[NCB]

OO it puts plenty of people off, but how do you quantify it! I suppose you could start by those who model in EM or 4mm. The reality is that it is a historical issue that there is no need to repeat - are you seriously saying that if 4mm scale was starting from scratch that the choice of track would by 16.5mm?

 

I don't think that anyone is talking about compromising the bodies - sure you would have to build in some looser tolerances (and perhaps compromise some under the footplate dimensions on steam locos) if you wanted very small curves.

 

Cheers, Mike

I can understand wanting dead scale, or something approaching that, track. When I moved into 3mm scale after a bit of thought I opted for 14.2mm track and have never regretted it. BUT, I did it with my eyes open. I knew it meant severe limits to the curves I could use. As I mentioned, I aimed for 40" minimum radius as the norm, 32" minimum if I had to, and ended up with one 29" radius curve which I can't avoid unless I rebuild the whole layout, which works, but I wish it wasn't there.  Those restrictions are there for both practical and aesthetic reasons; practical, because I can't use less, and aesthetic, because what is the point of dead scale track if you're going to bend it around train set curves. If anything, narrower track looks better on such curves.

 

To put it another way, I have an 8'6" x 10'3" room which houses the layout. While I was getting started in 3mm I also built an HO U.S. layout which had 3 circuits of the room, set in mountain scenery, purely for fun using that space. In 3mm on 14.2mm track I can just about get in an L shaped terminus to fiddle-yard layout. A circuit isn't really feasible, or not one which is worthwhile. I'm happy with that, because my main interest is in building locomotives and rolling stock, along with the challenge of using scale track, which I hope looks realistic; the layout is good enough to provide somewhere to use that stock. But it would bore the pants of anybody who's interested in operation.

 

I think you have the same thing with EM/P4 and OO. EM/P4 people recognise the restrictions they are faced with by going down that route.

 

If 4mm started now? You're faced with the same problem. If you want bodies which are essentially to scale then you can only have scale track if you have wheels fairly near to scale AND you accept that sharp curves are out.

 

Cheers

Nigel

[AndyID]

Well said Nigel. I suppose if I had nothing better to do (come to think of it, I don't believe I do )  as an exercise, it might be interesting to work out what gauge "00" could be with today's wheel standards etc.

 

But before I could do that, I would need to understand a whole lot about the requirements. (Min radius, max rigid wheelbase, planar deviation, "snap track" or flex track, rail section, etc., etc., etc.)

 

On the other hand, I could make a wild stab at it and guess that it might be about half-way between 16.5 and 18.2 (EM) - say 17.3 mm for a proto gauge of 1318 mm (4'4")

 

Andy

[jmh67]

I, for one, would love to see proper 1:120 models of British outline (and likewise, 1:87 or 1:160). For those who are interested in both continental and British railways, that would be of advantage - what with ferry boat wagons, the Eurostar, or class 59. Maybe, if a manufacturer would start making models of these in addition to purely continental outline ones, it would be less of an entrepreneurial risk than starting a whole new range at once. It could kick off a new game, or it could not, but the models were not "lost in space" even if they decide to stop the production run some time.

 

By the way, there were overscale continental models, too, but they have been largely replaced by true-to-scale ones.

 

Martin

[johnarcher]

I, for one, would love to see proper 1:120 models of British outline (and likewise, 1:87 or 1:160). For those who are interested in both continental and British railways, that would be of advantage - what with ferry boat wagons, the Eurostar, or class 59. Maybe, if a manufacturer would start making models of these in addition to purely continental outline ones, it would be less of an entrepreneurial risk than starting a whole new range at once. It could kick off a new game, or it could not, but the models were not "lost in space" even if they decide to stop the production run some time.

 

By the way, there were overscale continental models, too, but they have been largely replaced by true-to-scale ones.

 

Martin

Basically what I thought, though with a more positive angle. The models of British prototypes used on the continent might be feasible, tapping into the large European TT market discussed above, but that is hardly the launch of a real British TT scale. As soon as that maker thinks of producing a purely British prototype where is the market - not all those Europeans, nor the British 3mm people? So some 1:120 models might be possible, but the establishment of that as a proper general British modelling scale seems very unlikely.

 

NCB said "If you want bodies which are essentially to scale then you can only have scale track if you have wheels fairly near to scale AND you accept that sharp curves are out". Seems a pretty good summary to me

[Hobby]

Commercially the narrower track in OO doesn't seem to put anybody off,

 

Because they don't have any choice!

 

I suspect most people would rather have HO standards if that were possible, however it's now far too late to do anything about it! Thanks for clarifying the motor position, do you have a link to the Mellor article or where it was published so we can read it?

 

It's worth bearing in mind when discussing clearances that production methods have moved on since the 1930s so what is possible now far outstrips what was possible back then so I suspect that HO British outline would be perfectly feasible now with very little compromise. I disagree with you regarding the narrow gauge of OO-16.5, I think it looks awful, only the use of the new "more scale" track makes it look acceptable... But that's just the way I see it, you obviously don't!!

[AndyID]

Because they don't have any choice!

 

I suspect most people would rather have HO standards if that were possible, however it's now far too late to do anything about it! Thanks for clarifying the motor position, do you have a link to the Mellor article or where it was published so we can read it?

 

It's worth bearing in mind when discussing clearances that production methods have moved on since the 1930s so what is possible now far outstrips what was possible back then so I suspect that HO British outline would be perfectly feasible now with very little compromise. I disagree with you regarding the narrow gauge of OO-16.5, I think it looks awful, only the use of the new "more scale" track makes it look acceptable... But that's just the way I see it, you obviously don't!!

 

Hi Hobby,

 

I agree that modern production methods will help, but only to a certain extent. The problem to be solved has to do with minimum radii, wheel base lengths and other factors.

 

If you want "true scale", pretty much everything has to be to scale, and that gets you back to something along the same lines as P4 with all its limitations.

 

Cheers!

Andy

[Hobby]

Yes I agree Andy. The majority of people who play trains (!), however, aren't bothered, so they accept 16.5mm gauge for OO scale and would no doubt accept the shortcomings to allow for sharp curves, etc., if they modelled British HO or TT!

[johnarcher]

Yes I agree Andy. The majority of people who play trains (!), however, aren't bothered, so they accept 16.5mm gauge for OO scale and would no doubt accept the shortcomings to allow for sharp curves, etc., if they modelled British HO or TT!

Probably so, so in that case why not just stick to 3mm scale on 12mm for British TT, with the wider gauges for those who care, rather than trying to start a scale that's completely new in a UK context?

[NCB]

I suspect most people would rather have HO standards if that were possible, however it's now far too late to do anything about it! Thanks for clarifying the motor position, do you have a link to the Mellor article or where it was published so we can read it?

 

 

George Mellor's article first appeared as the introduction to his 1938/39 catalogue. I found it quoted in Michael Foster's "Hornby Dublo Trains", published somewhere around 1988 by New Cavendish Books.

 

Cheers

Nigel