31 mm, 31.2mm or 31.5mm that is the question!

[martin_wynne]

SURELY, we want to get as close as possible to scale track? So, if the wheels are wrong B to B, why don't we do something about that, instead of narrowing our track gauge? Is it beyond someone to come up with better axles? Slaters, for example?

 

Hi Jeff,

 

What you are asking for already exists, and has done for 40 years. No-one needs to come up with anything better. It's called ScaleSeven (S7), see: http://www.scaleseven.org.uk

 

But the vast majority of 0 gauge models do not have S7 wheels. These models can't suddenly unexist or be converted to S7. The installed base of 0 gauge models is overwhelmingly running on "0 Fine" wheels.

 

The principle therefore is to accept these wheels "as-is" for maximum interchangeability, and then provide a range of track standards for them, which modellers can choose according to their individual circumstances.

 

A way forward which requires everyone to change or modify their existing wheels is just daft.

 

regards,

 

Martin.

[wenlock]

OK, I'm getting there.

 

But it would appear that we are getting this back to front.

 

SURELY, we want to get as close as possible to scale track? So, if the wheels are wrong B to B, why don't we do something about that, instead of narrowing our track gauge?

Is it beyond someone to come up with better axles? Slaters, for example?

 

It just seems odd to me that in a scale when we can get so much RIGHT, we are willing to move to 4' 6" track gauge........

You make a good point JeffP, I guess in an ideal world, that's where we should be heading! My problem is that I and I'm assuming a lot of other 7mm modelers, have built a fair bit of stock already and don't want to spend the time and hassle changing them. The narrow gauge scenario, although flawed allows the use of existing stock and wheel sets , on track that has a "better" appearance. I guess in the end it's all a compromise and that we should all start modeling in Scale 7, with it's attendant problems.

 

Best wishes

 

Dave

[wenlock]

Looks like Martin and I are on the same page! He types faster though

[Kenton]

These are not peculiar gauges. They are in established use and have had names for 10 years!

 

Thanks Martin for the clarity. However, it is not so much that all these track gauge variants ARE possible and may have "advantages" over each other. (just as in the case of OO/OOSF/EM/P4) it is that I cannot see why we should even be making all these options in the first place. We seem to be doing it simply because we can and am surprised that we haven't yet come up with a guege declaring the use of a 3rd decimal place. Just because it is possible doesn't make it right or universally popular.

[Kenton]

A way forward which requires everyone to change or modify their existing wheels is just daft.

 

No more or less so than changing their track.

[wenlock]

Just because it is possible doesn't make it right or universally popular.

Nothing to do with being "right or "popular" just an option worthy of consideration. If it's not for you, then fine. "Vive la difference" and all that!

[martin_wynne]

Just because it is possible doesn't make it right or universally popular.

 

Hi Kenton,

 

Not sure where right and wrong come into it? The situation seems simple enough to me:

 

1. Most modellers buy ready-made wheels. They don't want to have to modify them, because then they become non-interchangeable -- you can't run your models on friends' layouts and they can't run theirs on your layout. The principle therefore is that wheels don't change.

 

2. Track however is built in the privacy of your own workshop, and there is no reason why it should be the same as anyone else's. You can build it to any dimensions you damn well like. The only requirement is that the wheels should run on it.

 

Providing the check gauge remains constant we can publish a dozen different combinations of flangeway gap and track gauge, or modellers can invent their own, to suit their individual conditions.

 

The important point to note is that all these track dimensions are intended for handbuilt track. No-one is proposing them for commercial manufacture.

 

And no-one is under the slightest obligation to use them if they don't want to.

 

regards,

 

Martin.

[Kenton]

1. Most modellers buy ready-made wheels. They don't want to have to modify them, because then they become non-interchangeable -- you can't run your models on friends' layouts and they can't run theirs on your layout. The principle therefore is that wheels don't change.

 

2. Track however is built in the privacy of your own workshop, and there is no reason why it should be the same as anyone else's. You can build it to any dimensions you damn well like. The only requirement is that the wheels should run on it.

 

Why is it I find these two statements at odds with each other?

 

Surely if it is a problem for someone else's layout "run your models on a friend's" then the same is must be true of running theirs on your layout. Whoever is making theirs non-standard/non-universal is the one making the change just for the sake of it.

 

and whilst I agree that what one person does in the privacy of their own home is totally up to them - they can run on 30mm for all I care (make their own wheels and track to suit and it may look better to them and be more rewarding. I still have an issue with anything that starts to proclaim it is the new (or old) standard.

[kevinlms]

Thanks Martin for the clarity. However, it is not so much that all these track gauge variants ARE possible and may have "advantages" over each other. (just as in the case of OO/OOSF/EM/P4) it is that I cannot see why we should even be making all these options in the first place. We seem to be doing it simply because we can and am surprised that we haven't yet come up with a guege declaring the use of a 3rd decimal place. Just because it is possible doesn't make it right or universally popular.

 

Doesn't the problem come down to the pioneers getting it wrong?

 

http://en.wikipedia.org/wiki/O_scale

 

So when or why did the track change from 1 1/4" to 32mm, presumably at the same time as the scale become 7mm to the foot?

 

Of course the original models were for the toy market and the attempts for people to make better scale models came about, utilising as much existing materials as practical.

 

I would agree that any who wants to do the job "properly", then they ought to use S7 standards (which you describe as track to 3 decimal places).

If they want to maintain some level of 'conformity; to allow sharing of locos & rollingstock between layouts belonging to friends & clubs, then another standard ought to be used. As Martin has described in detail the variations, it comes down to standard RTR 32mm track (Peco etc) or 31.5mm track gauge.

 

Kevin Martin

[martin_wynne]

Surely if it is a problem for someone else's layout "run your models on a friend's" then the same is must be true of running theirs on your layout.

 

But if neither of you change your wheels, the models remain interchangeable on both layouts, and on every other 0 gauge layout. What's more you can use different track standards on different parts of the same layout -- 0-MF on the front, Peco in the fiddle yard, because all the wheels are still the same.

 

It's changing the wheels which makes things non-interchangeable. If everyone uses the same wheels, all models run on all layouts, regardless of the track standard adopted for each one. Peco for rough and tumble and sharp curves, fine-scale hand-crafted pointwork on gentle curves at the front, or on a small shunting plank layout.

 

For 0 Fine wheels the rules are these:

 

The check gauge must be 30.0mm

 

The check span must not be more than 28.8mm to accept wheels set at 29.0mm B-B.

 

The flangeway gap must be at least 1.2mm to clear flanges 1.0mm thick, and not more than 1.5mm to support wheels 3.5mm wide.

 

Within that you can invent your own to suit your prevailing curves and quality of running desired. For example 31.4mm with 1.4mm flangeways would be fine, giving a check span of 28.6mm. Or 31.3mm with 1.3mm flangeways, giving a check span of 28.7mm.

 

But the finer you go, so the more likely it becomes that some older wheels will fail to run, and sharp curves will become a problem. The great advantage of 0-MF at 31.5/1.5/28.5 is that it fully supports the finer wheels while still accepting the vast majority of existing wheels, and allows typical model curves to be used.

 

regards,

 

Martin.

[Kenton]

OK so it doesn't really matter one way or the other between 31.5 and 32 (if I have got that one correct) and those of us who use Peco (32) will have no problems in running stock on 31.5mm or on adding track hand built to 31.5 or 32 as I still cannot see a difference of 0.5mm.

 

Also for those who wish to apply S7, build track and stock accordingly and use appropriate wheels then fine - the two have never been compatible. But I cannot see why the range in between.

 

Going back to compare to the 4mm world. The rationale to go P4 from OO always made sense - the only reason for EM was that it was easy to do and in many cases all that had to be done was change the B2B. The choice of 31, and worse 31.2, just doesn't seem to make any sense to me.

[martin_wynne]

track hand built to 31.5 or 32 as I still cannot see a difference of 0.5mm.

 

Hi Kenton,

 

The difference in track gauge is irrelevant. The significant difference is in the flangeway gap. With 1.75mm flangeways (32mm, 0-F) Slaters 3.5mm-width wheels will bump in the crossings. With 1.5mm flangeways they won't. The running is much smoother as they remain fully supported through the crossings.

 

The change in track gauge is simply to keep the flangeways symmetrical, since the check gauge is fixed at 30.0mm. If the flangeways aren't symmetrical it is very difficult to construct complex formations such as tandem turnouts which require parallel-wing crossings.

 

But reducing the track gauge also removes some of the gauge-slop in the 32mm standard, which helps when propelling loose-coupled wagons.

 

regards,

 

Martin.

[ozzyo]

OK so it doesn't really matter one way or the other between 31.5 and 32 (if I have got that one correct) and those of us who use Peco (32) will have no problems in running stock on 31.5mm or on adding track hand built to 31.5 or 32 as I still cannot see a difference of 0.5mm.

 

Hello Kenton,

 

you say "I sill cannot see a difference of 0.5mm" but you can see the difference of 0.6mm between EM and P4. These two will not work together.

 

But 32mm FS and 31.5mm work together as they both use the same wheel sets, set to the same B2B of 29.2mm the main difference is in the look through the point work. If you have not seen a layout built with 31.5mm point work how can you say what your saying.

 

The plain track can still be built to 32mm but the point work to 31.5mm and that will give you the look of finer track work.

 

All the wheels are still the same.

 

This is not a gauge war like 4mm as 32mm and 33mm are so close together not like 16.5mm and 18.83mm.

 

ATB

 

OzzyO.

[3 link]

Hi Kenton,

 

The difference in track gauge is irrelevant. The significant difference is in the flangeway gap. With 1.75mm flangeways (32mm, 0-F) Slaters 3.5mm-width wheels will bump in the crossings. With 1.5mm flangeways they won't. The running is much smoother as they remain fully supported through the crossings.

 

The change in track gauge is simply to keep the flangeways symmetrical, since the check gauge is fixed at 30.0mm. If the flangeways aren't symmetrical it is very difficult to construct complex formations such as tandem turnouts which require parallel-wing crossings.

 

But reducing the track gauge also removes some of the gauge-slop in the 32mm standard, which helps when propelling loose-coupled wagons.

 

regards,

 

Martin.

 

Hi Martin,

 

I concur with all of your statement above, and also with S7 it is not just a case of adjusting the back to back like you can with say EM, the wheels sets will all need their flanges and treads turning down aswell.

 

I hope folk do not think I have anything against the Peco turnouts as I think that they have done a great job of trying to keep EVERY o gauge modeller happy, like most things " you can't please everyone all the time, but you can please some of the people some of the time"

 

ATB,

 

Martyn.

[martin_wynne]

I hope folk do not think I have anything against the Peco turnouts

 

Hi Martyn,

 

The real argument is with Slaters, who unilaterally reduced the wheel width to 3.5mm, reduced the flange thickness to 0.8mm, and increased the back-to-back to 29.2mm. They were perfectly entitled to do that if they wished of course. But not to suggest that the wheels were still compatible with the existing 0 Fine 32mm track standard.

 

But the wheels looked so good that everyone wanted to use them, and other manufacturers copied them, so that this became the de facto "industry standard" wheel for 0 gauge.

 

The reduced-gauge variant track standards have all arisen to address the problem of running these wheels mixed with older wheels still compliant with the original 0 Fine standard.

 

regards,

 

Martin.

[dikitriki]

Hi Chaps

 

Here's a formation built to 31.5mm. I can run all my stock over it, but more to the point, so can everyone else, without changing any wheels.

 

To my eye, it looks a lot better than 32mm pointwork, and if you are building your own, just as easy.

 

 

Richard

[JeffP]

Ah...the penny drops....Slaters changed their wheel standards.

 

Amazing, really, that in 4mm scale, the battle is to get to more scale track, whereas in 7mm scale, the battle is to get AWAY from scale track.

 

It may LOOK better, but if it's a scale inch narrower, I for one ask, WHY?

 

Could the finer flangeways etc not have been incorporated into 32mm gauge track?

 

And to think I naively thought I'd left this sort of argument behind when I left 4mm scale modelling...........

[martin_wynne]

Could the finer flangeways etc not have been incorporated into 32mm gauge track?

 

Hi Jeff,

 

Then the older wheels set to 29.0mm back-to-back would not run without having their back-to-back dimension increased. The whole object of the exercise is to allow the majority of existing wheels to run without changing them.

 

And to think I naively thought I'd left this sort of argument behind when I left 4mm scale modelling...........

 

Which argument? There isn't an argument. Various standards are available and you can choose whichever you prefer. No one is going to argue that you shouldn't. If you want to go closer to exact scale then S7 is ready and waiting for you, and has been for 40 years.

 

regards,

 

Martin.

[3 link]

I find it amazing just how passionate some folk are on the subject of gauge standards, as a lot of you know an almost identical thread is running on the guild forum as I speak. And most of the modellers on there agree to disagree .

 

ATB,

 

Martyn.

[JeffP]

So........assuming I wanted to run stock with the newer standard wheels: I prefer 32mm gauge, so IS there a standard I could adopt for finer flangeways with that gauge, and if so, what is it?

[Trevor H]

My previous adventure into O gauge where I started afresh into 7mm, I opened the back to backs on my stock, which allowed me to run on 32mm track and still have the tighter tolerances on the pointwork. But this time around I will go with building all pointwork at 31.5mm.

 

In my view you have three main choices:

 

S7 - which means starting or changing all your wheels to S7 standards and building all your own trackwork, which all looks very nice. But this brings other problems much like P4 and you are restricted to running only on S7 trackwork.

 

32mm - Ideal if you don't want to build your own pointwork and stick with using Peco points. Which is not a problem, but it has the wider gaps between check rails or frogs, which causes the wheels to drop when passing through and looks less prototypical.

 

31.5mm - For people who wish to build their own pointwork. You can still use the standard 32mm flexitrack from the likes of Peco and C&L, but the points themselves are reduced to 31.5mm which gives a better looking appearance and much smoother running.

 

Standard finescale O gauge wheels from Slaters, Peco, Heljan etc, will run on both 31.5mm and 32mm trackwork. Where as S7 wheelsets are restricted to S7 trackwork only, so for personal reasons the later is a non starter, due to the restriction on what layouts or test tracks I could run my stock on.

 

Finally where does one get 31.5mm track gauges or is it a case of making your own.

 

Trevor.

[Trevor H]

So........assuming I wanted to run stock with the newer standard wheels: I prefer 32mm gauge, so IS there a standard I could adopt for finer flangeways with that gauge, and if so, what is it?

 

If you are building your own points, then use standard 32mm flexitrack and reduce/taper the pointwork down to 31.5mm. Its only 0.5mm to lose, but makes a huge difference on appearance and running.

[bcnPete]

Finally where does one get 31.5mm track gauges or is it a case of making your own.

 

 

P.S. You can buy the gauges from Debs of this parish.

 

I think Debs can help out here...

[Trevor H]

 

I think Debs can help out here...

 

Thanks, Pete.

[JeffP]

How does one contact Debs?