Society Gauge Widening Tool

[Russ Elliott]

Surely those values are constant but unaffected were GW to be introduced?

The problem, Julian, as is commonly recognised (by Martin et al), is where wings are also expected to act as checks, as in adjacent vees of a three-way, and the Ks of diamonds, where there is a discontinuity in the adjacent running rail. It is in that area where the P4 values (specifically, BBmin) begin to become suspect. Hence the historical move to get a more generous BB, if not officially part of the values in the 'standard', to at least be mentioned in the standard as a way of alleviating the problem. That was one of the big battles in issue 2 of the standard. Fortunately, I was young enough and pig-headed enough to drive it through. There was lots of blood on the floor. Again, everyone was equally offended at the result, but everyone survived.

[Julian Roberts]

The problem, Julian, as is commonly recognised (by Martin et al), is where wings are also expected to act as checks, as in adjacent vees of a three-way, and the Ks of diamonds, where there is a discontinuity in the adjacent running rail.

Russ I am sorry to be thick here, and I certainly don't want to resurrect past battles, but the Digest's

Gauge widening should not be applied to any sections of pointwork where CG, CF or BC dimensions are specified

can be read by someone like me in two ways. If I had made more complex pointwork than a turnout I might not have this misunderstanding, but that statement can be read either that

1. GW should not be applied to (any) pointwork (because) CG, CF or BC dimensions are specified. (in other words, all pointwork)
OR
2. GW should not be applied to (that kind of pointwork where) CG CF or BC dimensions are specified. (in other words, more complex pointwork)

Me "Joe Nobody" can read that, see that the Check Gauge, Crossing Flangeway and Between Checks values are specified for an ordinary turnout, and think that there must be no GW.

For an ordinary turnout, like B8's I have made, or A6's come to that, I don't see what the problem is getting in some GW so long as we use the Check Gauge Tool to gauge the check rail from the crossing V and knuckle area...nor why if the amount doubled from (say) 0.1mm to 0.2mm for an A6 for example, there should be any greater problem.

[Martin Wynne]

For an ordinary turnout, like B8's I have made, or A6's come to that, I don't see what the problem is getting in some GW so long as we use the Check Gauge Tool to gauge the check rail from the crossing V and knuckle area

Hi Julian,

There isn't a problem, and that's the correct way to set check rails.

Everyone who builds track knows that, but having a model railway to get on with they don't think to come back and argue with the written word from the 1960s. No-one is going to be daft enough to add so much gauge widening that the wheels fall off the rail.

The idea that the MRSG somehow knew more than anyone else at the time runs through many topics here, and I don't believe it. They were just doing their best with the available knowledge and practice, like everyone else.

When established standards don't give the required answer there are two options:

1. try to get them changed. Hard work and endless arguments.

2. ignore them and carry on. Dead easy.

Martin.

[Russ Elliott]

Julian - would you call this 'simple', 'ordinary', or 'more complex' pointwork?

curved-turnout.png

[Julian Roberts]

Julian - would you call this 'simple', 'ordinary', or 'more complex' pointwork?

curved-turnout.png

Not exactly simple...!

[Russ Elliott]

Ah, so you now seek to differentiate between 'all', 'simple', 'ordinary', 'more complex', and 'not exactly simple'?

[Julian Roberts]

I am using words too loosely. I've seen ambiguities in my question so will see if I can edit that post but will have to go offline soon.

[Julian Roberts]

Hi Russ, rephrasing the question

Gauge widening should not be applied to any sections of pointwork where CG, CF or BC dimensions are specified

I read that as saying that there is no GW in pointwork but wondered if I was understanding correctly. Then above you have said that it is in the case of K crossings, three ways, etc - implying not for all pointwork?

[Russ Elliott]

Gauge widening should not be applied to any sections of pointwork where CG, CF or BC dimensions are specified

This objective should, ideally, apply to all pointwork.

My remark about about Ks and 3-ways was related but not strictly germane to GW.

[grovenor-2685]

Hi Russ, rephrasing the question

Gauge widening should not be applied to any sections of pointwork where CG, CF or BC dimensions are specified

I read that as saying that there is no GW in pointwork but wondered if I was understanding correctly. Then above you have said that it is in the case of K crossings, three ways, etc - implying not for all pointwork?

Julian,
You are converting a recommendation "should not" into a definate "is no". Its the same as the full size, avoid it if possible but in extremis you can do it.
On DLR we don't use GW, even on 40m radius, but then our longest wheelbase is 2.2m
On those B8s you built, assuming one side is straight you certainly don't need any. An A6 usually not either but you might if having to cope with long wheelbase stock.
Russ' example drawing above looks like he might have set the inner radius to the famous 528mm, in which case it will be difficult to get away with no GW and still run the typical 0-6-0 etc.
There is no simple answer that covers every case, which is why "should" gets used.
Regards

[Russ Elliott]

I note the DLR has adopted moving vees for its 'higher speed' turnouts. Nice. No wonder Keith can't get excited about CG and CF anymore...

[Russ Elliott]

Russ' example drawing above looks like he might have set the inner radius to the famous 528mm, in which case it will be difficult to get away with no GW and still run the typical 0-6-0 etc.

No, I have no idea what the inner radius is. I just Google 'curved turnout' and took the first decent example.

My focus was not on the inner curve at all. My question to Julian, when he returns, will concern the outer curve.

[Martin Wynne]

ts the same as the full size, avoid it if possible but in extremis you can do it.

Hi Keith,

Why the "avoid if possible"? I can't see any downside other than the visual effect of a wider flangeway gap. And it may be beneficial for some future exotic item of rolling stock that you don't yet know about, even if you don't strictly need it now. If you go mad on the widening you may get some buffer-locking when propelling short 4-wheel stock. But sensible P4 modellers don't tend to go mad.

If you use the 3-point gauge you get some gauge-widening anyway, whether you want it or not.

If you say "avoid if possible" you then get another 12 pages of how to decide when to use the 3-point gauge, when not to, and how to arrange the transition from one to the other.

On the other hand, if you use functional check chairs, they are gauged to the check rail using the check gauge, not using the track gauge. So whether you get any gauge widening is determined by the chair size and not any track gauge, 3-point or otherwise.

After 12 pages, I still can't see where anyone is having any actual problems?

regards,

Martin.

[Martin Wynne]

My question to Julian, when he returns, will concern the outer curve.

If you gauge-widen the outer curve through a crossing, there is a risk of rough running if the wing rail pulls the wheelset away from the outer rail.

However the outer curve through a crossing is almost always quite gentle (otherwise the inner curve would be excessively sharp in most cases), so the amount of gauge-widening applied is likely to be quite small. Especially using the short P4 3-point gauge.

Not Julian.

[Russ Elliott]

If you gauge-widen the outer curve through a crossing, there is a risk of rough running if the wing rail pulls the wheelset away from the outer rail.

Looks like, after 12 pages, you've put your finger on an actual problem, Martin.

Depending on one's wheel setting, it might be a minor problem if GW is not applied to that outer curve. If any GW is applied however, the problem is no longer a minor one.

[grovenor-2685]

I note the DLR has adopted moving vees for its 'higher speed' turnouts.

Not so actually, the "swing noses" as they are called are only used where there is difficulty meeting the noise levels (mandated in the act) ie they are there to reduce wheel/rail noise generation. All bar one are at Canary Wharf on 100m turnouts with a 25kph speed limit. The other is at Bow Church and has a 40kph limit. The higher speed turnouts on DLR at Royal Mint St. Pudding Mill Lane and Stratford are all fixed crossings.
Regards

[grovenor-2685]

If you use the 3-point gauge you get some gauge-widening anyway, whether you want it or not.

Depending on how you use it.

After 12 pages, I still can't see where anyone is having any actual problems?

But you should be able to see several questions asking what problem was encountered, all of which were ignored.
regards,

[Russ Elliott]

Thanks Keith. The one at Bow Church is ace. I'm betting you'll be putting in more in the future.

[Julian Roberts]

My focus was not on the inner curve at all. My question to Julian, when he returns, will concern the outer curve.

Russ
Dipping in briefly, is there still a question now that Martin has answered it?

[Martin Wynne]

is there still a question now that Martin has answered it?

Russ hasn't asked it yet.

Martin.

[Julian Roberts]

But you should be able to see several questions asking what problem was encountered, all of which were ignored.
regards,

Sure Keith,
I answered fully to Jim SW on Aug 18 why I was persuaded that going overgauge gave more reliable running on a very limited application, the switch of a B8. My original email to Russ was on the same topic. This is what gave me the reason to ask the question originally.

viewtopic.php?f=5&t=4732&start=150

[grovenor-2685]

Julian,
Do you mean this entry?

I've made four B8 turnouts, one experimental and then three for the West of Scotland 4mm Group extension that Allan is talking about (by the way thanks for the plug, Allan!) and found that to get good running through the switch it was critical that the gauge was at least 0.1 wide, and that as Mark says, to have it wider (by maybe filing a bit more off the switch blade gauge corner) improved reliability. I have only been able to test them at home with just enough track in advance of the switch to place a loco, as the baseboards are only getting completed now, but it has been enough to convince me of the importance of having the gauge wide enough through the switch, as many people have said ad nauseam on other parts of the Forum - though maybe not as "ad nauseam" as my contributions to this thread saying the same things over and over again....

Not having tight gauge through the switch is, as you say, mentioned quite often because its easy to end up with tight gauge there. However that has completely nothing to do with gauge widening on curves or the triangular gauge. Which is why I did not consider it as demonstrating any problem with those, or with the standard. Its just a common beginners' error which is easily avoided once it is understood.
Regards

[Julian Roberts]

However that has completely nothing to do with gauge widening on curves or the triangular gauge.
Regards

Keith I think you said above that a B8 doesn't need any GW. What I was finding was that I needed at least 0.1, perhaps going up to 0.2, GW on the switch and the curving area where the blade flexes for reliable running of even a short wheelbase wagon that I knew to run reliably on the group layout. In other words better too much than too little - but obviously we are talking angels on a pinhead stuff, 0.1mm increments. Around that time Mark Tatlow's checklist was in the S4News, saying the same kind of thing though without numbers. I wrote to Russ about his CLAG stuff on easing the traverse through the switch but for reasons I now understand he was unable to reply till last Saturday. Not to mention "A Luddite's View" in the S4 News at the time by the EM chap (sorry name escapes me) talking about the running of P4 in general being good on exceptional layouts but not universally. That was the general background at the time I started this thread, and since then the subject took a route of its own. It's not me that's written these 12 pages! - and to the extent it is me I have used photos which bulks it out as more swish diagrams are not part of my modelling skills...

So seeing the original quote of Russ' (the start of the thread) that we get just half what the prototype might get simply posed a question. My experience, or more plainly lack of it surely doesn't invalidate any reason for asking a question?

It seemed to me that any extra tolerance we can build in for reliability of running even if it's just 0.1mm is to be embraced with open arms. Anyway we have been round and round that one, I know you say there is already enough. I have written for the next Snooze about my loco building which uses a similarly minute tweak (nothing to do with BB though) to improve roadholding, which I suppose you, Jol and everyone may utterly detest. It's not secret as I already put stuff on the Forum about it a few years ago now.

[Russ Elliott]

Julian - I think you and Keith are talking at cross-purposes. Keith is not saying do not implement GW over a switch area, he is simply pointing out that the triangular gauge would not, because it cannot, be used in the switch area.

It is one of the ironies of the standard that the historical arguments all raged about what is happening at the crossing. The switch area was neglected.

Considerations for the crossing area are different to those for the switch area.

[jim s-w]

Sure Keith,
I answered fully to Jim SW on Aug 18 why I was persuaded that going overgauge gave more reliable running on a very limited application, the switch of a B8. My original email to Russ was on the same topic. This is what gave me the reason to ask the question originally.

viewtopic.php?f=5&t=4732&start=150

You did? I saw a reply about why you agreed with the theory but I never saw anything saying what the actual problem you were having was, which is what Keith was asking.

Cheers

Jim