00 gauge Standards

[hayfield]

Terry:

 

I'm afraid you don't quite understand what you are quoting , or its context, never mind actual standards used on OO layouts on the British exhibition circuit. 

 

Very few people in Britain work to 16.2mm gauge - most of them have probably posted in this or associated threads . Next to nobody has heard of the NEM track standard. Most British modellers think that NEM is the name of a type of socket for couplings. Those layouts are all , to the very best of my knowledge, handbuilt OO track to BRMSB OO standard  

 

 

Stephen / Ravenser

 

If you take all shows into consideration the most common track system used is not hand built but Peco. Or do you just disregard all the small little shows that happen every week up and down the country. Yes if you go to the larger shows there will be a selection of layouts with hand built track, a great many are to P4 and EM gauge though

 

Does it bother any of us, if there are only a few of us using 00sf, strange though Peter has to keep restocking his gauges. Do we care if there are loads of modellers using 00bf/DOGA fine, DOGA intermediate, no it does not. I have been teaching some one to build in the latter gauge this afternoon, pity the DOGA does not advertise wing rail gauges or check rail gauges though, I had to cut a piece of 1.25 mm strip of a length I got milled, no doubt he will want to use my check rail gauges as well 

 

Now several times you have been asked about your stance and the association you are stoutly defending who's objectives are:-

Our objectives are-

• To welcome ALL modellers with an interest in OO.

As far as I know those of us who model in 00sf are 00 gauge modellers, why are we not considered part of the ALL

 

Do your pals at the DOGA view out tiny group with the same disdain as you do, as for your wonderful set of standards why could I not build a curved diamond crossing using DOGA standards without a few going astray, thankfully Martin suggested I try 00sf, and guess what it worked.

 

Please not to all those who build to any of the 00 gauge standards (or any other standard), that's including AndyID with his cut down version, if it pleases you and meets your requirements do continue and enjoy yourselves. All I ask is that you respect mine and others views on their chosen standards.

 

By the way, I have just built an 00sf B7 turnout which I am happy to lend out to anybody who is interested in evaluating it free of charge, except for the reimbursement of postage

[martin_wynne]

I shall be trawling Warley looking for all the hand built OO gauge track on layouts and mercilessly grilling the operators about their standards

 

Make sure you ask the person who actually built the track, otherwise you will get a dozen different answers.

 

Martin.

[RichardS]

Thanks Ravenser. I had no plans to change wheels to ultrascale, I was just researching. (couldn't afford to at those prices anyway)

On a similar line I once heard a trader at a general show in Norfolk when asked by a visitor what the difference between OO and HO was, answer "nothing, they're the same". I was tempted to intervene but didn't - there seemed no point.

I think it is easy to overlook that people on this kind of thread on RMWeb are an informed bunch generally although we are all still learning - some more than others (me)- but that in the big wide world there's a lot of ignorance (not meant in an insulting way of course).

Regards

Richard.

[martin_wynne]

IAs a relative novice still investigating this whole subject I was surprised to read the following answer to a question on the Ultrascale Wheels website in their FAQs.   

 

What is 'OO' Fine scale?

'OO' Fine scale is the standard to which we manufacture our 'OO' wheel sets. These sets use the same track gauge as 'OO' (16.5mm) together with our 'OO'/E.M. wheel profile. This means that they are not suitable for out of the box 'set track' and should only be used for fine scale track work like Peco code 75 and code 100 as well as other fine scale track. (my italics and u/l)

 

This illustrates my previous point that there is nothing wrong with the 00 standards. It is the model trade which makes a dog's breakfast of it all and does 00 modellers no favours at all. The obvious move would be for an organisation claiming to represent 00 modellers to engage with traders, supply leaflets, data sheets, product stickers, web site advice, etc.

 

Just to clarify the specific point, Ultrascale wheels are not suitable for Peco, 00-BF, DOGA-Intermediate, track. They will fall into the crossing gaps (frog gaps). Gordon S of the Eastwood Town layout posted a picture showing an Ultrascale wheel which had done exactly that.

 

Ultrascale wheels are suitable for 4-SF (00-SF), DOGA-Fine and EM track.

 

Martin.

[RichardS]

Martin, I shall record all the answers and then remove the pin from my lapel - which I prepared earlier - close my eyes and jab it in my notepad.

[RichardS]

As a footnote to my previous post....If anybody feels a sudden stabbing pain on 28/29 Nov.... it's nothing to do with me

[nswgr1855]

Terry:

 

I'm afraid you don't quite understand what you are quoting , or its context, never mind actual standards used on OO layouts on the British exhibition circuit. 

 

A paragraph of very general comments , half a century old, doesn't actually help your argument.

 

There's no doubt that the BRMSB OO wheel standard did not quite match the BRMSB OO track standard. I would accept that a Romford wheelset (which is to the BRMSB OO wheel standard) might well experience drop in on a 1:12 crossing - though the actual drop will be very very slight. In that respect  I'd accept the MRSG quote

 

 

(In the historical context , they were probably trying to suggest that the then EM gauge standard , drawn up by the BRMSB in 1941-2, was unsatisfactory and should be replaced by their P4 standard)

 

However RP25/110 is slightly broader than the BRMSB OO wheel , and is a perfect fit for BRMSB OO track. There's no wheel drop if the maximum flangeway is 1.27mm or less . BRMSB OO is 1.25mm - DOGA OO-Intermediate permits flangeways in the range 1.25mm-1.15mm

 

The MRSG was probably also criticising the BRMSB dimensions as untoleranced

 

Most importantly in all cases with wheels to either BRMSB OO or Intermediate the checkrails are properly operative  (Wheels commonly known as RP25/110 and Romfords..). Slight dropin under certain circumstances could be tolerated (if you have to use Romfords as "nearest equivalent")- checkrails that don't do their job are a much more serious problem  with genuine consequences

 

What your quote does not support is your claim that it isn't possible to build complex pointwork to 16.5mm gauge with 1.25mm flangeways, and that such pointwork won't work if you build it

 

To be honest I think you've made the same objection to every 16.5mm gauge track standard you've ever come across, and therefore you're implicitly claiming that complex pointwork can't be built successfully in 16.5mm gauge at all. Nobody in Britain will buy that. We've seen it done in practice far too often

 

(I've got a 16.5mm gauge single slip on my own layout. To borrow a notorious phrase "It works just fine")  

 

Very few people in Britain work to 16.2mm gauge - most of them have probably posted in this or associated threads . Next to nobody has heard of the NEM track standard. Most British modellers think that NEM is the name of a type of socket for couplings. Those layouts are all , to the very best of my knowledge, handbuilt OO track to BRMSB OO standard  

 

P.S:  Does the AMRA still recognise 16.5mm as the track gauge for standard gauge Australian outline in HO . Or have you used your position as AMRA Secretary to "derecognise" 16.5mm gauge for HO in Australia? And has the hobby at large followed that lead?

 

I did not say you cannot build complex trackwork to 16.5mm gauge with 1.25mm flangeways. In fact I have built a single slip to the above nominal dimensions. The gauges used were to the OLD AMRA H0 standard. What I did point out was you cannot comply with the 00 gauge DOGA standard. The standard does not add up. I will go over it again. For a K crossing in a crossover, the maximum check face to check face dimension = or is larger than the minimum track gauge + a realistic tolerance - (2 x minimum flange way). Using the DOGA numbers we get 14.1mm maximum check face to check distance which is less than 16.5mm + 0.1mm (a tolerance you may get with roller gauges) - 2 x 1.15mm. The problem using RP25/110 flanges are they are unnecessarily fat flange (I note it is not toleranced) resulting in a tighter tolerance on your wheel back to back dimension which makes it harder to get right. The flange profile is not as good as the AMRA alternative according to some experiments I did about 10 years ago.

 

The AMRA standards can be found at http://www.amra.asn.au/standards.htm.  If you look at the intermediate track standard you will find the H0 gauge recommended dimensions for crossing V's and K's are as follows; track gauge 16.5mm to 16.6mm, flange way 1.2mm to 1.3mm. Note the track gauge limits in this standard and the fine tolerance standard are 16.2mm to 16.8mm. Put another way 16.5mm +/- 0.3mm. Also note both standards share the same check gauge of 15.2mm. This is the same as most Peco turnouts and 00-SF. The benifit of this is I can mix and match my old track with my newer fine tolerance track without changing wheels on my RTR models. As others have pointed out, the finer tolerance 1mm flangeways result in minimal wheel drop with finescale wheels, and eliminate derailments on K crossings because wheel and track clearances are much closer to scale.

 

I have not been secretary of AMRA for quite some time, however I am still on the committee of management. 

 

Cheers,

 

Terry Flynn

[hayfield]

This illustrates my previous point that there is nothing wrong with the 00 standards. It is the model trade which makes a dog's breakfast of it all and does 00 modellers no favours at all. The obvious move would be for an organisation claiming to represent 00 modellers to engage with traders, supply leaflets, data sheets, product stickers, web site advice, etc.

 

Just to clarify the specific point, Ultrascale wheels are not suitable for Peco, 00-BF, DOGA-Intermediate, track. They will fall into the crossing gaps (frog gaps). Gordon S of the Eastwood Town layout posted a picture showing an Ultrascale wheel which had done exactly that.

 

Ultrascale wheels are suitable for 4-SF (00-SF), DOGA-Fine and EM track.

 

Martin.

 

Martin

 

I may have misunderstood Ravenser (quite easy as his replies are usually over long) but I thought in one of his replies he stated that Slater/Gibson and Ultrascale wheels are not suitable for 00sf. I did query it but as usual he is very selective in his replies

[hayfield]

Just a quick heads up

 

The chap who I was introduced to came and saw me yesterday, a very quick whistle stop view of Templot and the revised plans (in 00bf/DOGE intermediate) of a junction he wants to build, he emailed fitted like a glove

 

As for the tuition, time was a slight premium, but as I had cut and gapped most of the sleepers prior to his arrival, the last few sleepers were cut and gapped. All but one switch rail, check rail and tiebar were made and fitted. He has made a C&L chaired turnout before, but things like set's and using jigs and gauges were explained.

 

Next will be watching him make a simple junction and help if needed, Templot tuition may take a bit longer

 

By the way he considers finescale is anything with code 75 rail including Peco track, nothing wrong with this and certainly believed DOGA intermediate standards are finescale when using code 75, which is fine with me

[Ravenser]

I did not say you cannot build complex trackwork to 16.5mm gauge with 1.25mm flangeways. In fact I have built a single slip to the above nominal dimensions. The gauges used were to the OLD AMRA H0 standard. What I did point out was you cannot comply with the 00 gauge DOGA standard. The standard does not add up. I will go over it again. For a K crossing in a crossover, the maximum check face to check face dimension = or is larger than the minimum track gauge + a realistic tolerance - (2 x minimum flange way). Using the DOGA numbers we get 14.1mm maximum check face to check distance which is less than 16.5mm + 0.1mm (a tolerance you may get with roller gauges) - 2 x 1.15mm. The problem using RP25/110 flanges are they are unnecessarily fat flange (I note it is not toleranced) resulting in a tighter tolerance on your wheel back to back dimension which makes it harder to get right. The flange profile is not as good as the AMRA alternative according to some experiments I did about 10 years ago.

 

 

Cheers,

 

Terry Flynn

 

 

Terry - with the greatest respect you clearly haven't done more than skim-read the datasheet, and hence your figures are wrong.

 

(Sheet is here)   http://www.doubleogauge.com/standards/commercialtrack.htm

 

- Firstly 14.1mm is the nominal width across check rails, and it's subject to a tolerance of 0.1mm plus/minus (Necessarily, since flangeways are permitted to be 1.20mm plus/minus 0.05mm, and there are 2 flangeways)

 

Therefore the maximum permitted width across check rails is 14.2mm - not 14.1mm  (The minimum permitted value is 14.0mm)

 

- Secondly 16.5mm is the minimum permitted track gauge, and up to 0.3mm of gauge widening is ;permitted on curves. 

 

You are demanding 0.1mm of  manufacturing tolerance in the system to allow for any effects of using roller gauges. That simply requires 0.1mm of gauge widening in what will no doubt be a curve  

 

16.5mm -  (2 x 1.15mm) =14.2mm. 

 

If you require 0.1mm of manufacturing tolerance on this, you get a gauge of 16.6mm - meaning 0.1mm of gauge widening, which is within permitted limits

 

(Of course the roller gauge may not produce 0.1mm error during construction. That's just a "worst permitted case" scenario)

 

The numbers add up....

[nswgr1855]

Terry - with the greatest respect you clearly haven't done more than skim-read the datasheet, and hence your figures are wrong.

 

(Sheet is here)   http://www.doubleogauge.com/standards/commercialtrack.htm

 

- Firstly 14.1mm is the nominal width across check rails, and it's subject to a tolerance of 0.1mm plus/minus (Necessarily, since flangeways are permitted to be 1.20mm plus/minus 0.05mm, and there are 2 flangeways)

 

Therefore the maximum permitted width across check rails is 14.2mm - not 14.1mm  (The minimum permitted value is 14.0mm)

 

- Secondly 16.5mm is the minimum permitted track gauge, and up to 0.3mm of gauge widening is ;permitted on curves. 

 

You are demanding 0.1mm of  manufacturing tolerance in the system to allow for any effects of using roller gauges. That simply requires 0.1mm of gauge widening in what will no doubt be a curve  

 

16.5mm -  (2 x 1.15mm) =14.2mm. 

 

If you require 0.1mm of manufacturing tolerance on this, you get a gauge of 16.6mm - meaning 0.1mm of gauge widening, which is within permitted limits

 

(Of course the roller gauge may not produce 0.1mm error during construction. That's just a "worst permitted case" scenario)

 

The numbers add up....

 

Even though I used the incorrect dimension for the  DOGA check face to check face limit dimension in my post, using the correct value it still does not add up. No on can be sure their track or their track gauge is exactly at 16.5mm.  For the DOGA standard to add up you need to have a larger check face to check face dimension or a smaller minimum track gauge or increase the minimum flange way. 

 

Again , one of the rules needed to be complied with for K crossings is maximum check face to check face dimension is larger or equal to the MAXIMUM track gauge - 2 x minimum flange way. The DOGA sum you have quoted uses the MINIMUM track gauge.

 

Cheers,

Terry Flynn.

[AndyID]

Did I hear someone mention me?

 

Anyway, here's something hot off the press you might want to sink your teeth into.

 

 

At first I thought this printing lark had no commercial aspects. Now I'm not so sure.

 

(If nothing else, it might serve as a means to give certain UK track manufacturers who, for the sake of argument we will say are based in Devon, a good prod in the rear end.)

[martin_wynne]

Perhaps we should let Terry and Stephen slug it out between them over K-crossings?

 

They will never agree, because the DOGA standards, and AMRA, and NMRA, are all flawed by double-dimensioning.

 

If you look at the 4-SF dimensions: http://4-sf.uk/dimensions.htm

 

you will see that they are all inter-related, each one has a Maximum or a Minimum, but not both.

 

The first thing to say about fixed K-crossings is that they are more critical than turnouts, so beginners should practice on turnouts first, before attempting diamonds and slips. And with wider than scale flangeways they are much more susceptible to mis-tracking than the prototype, so in 00 and EM I would suggest using switch-diamonds instead (movable K-crossings) at angles flatter than about 1:6 (the prototype limit in straight track is 1:8 ). Switch-diamonds are a lot easier to build, less critical, work perfectly, and give the prototype impression of being longer crossings. The only down-side is the need for extra point motors.

 

Getting back to fixed K-crossings, the extra factor to consider is that there is a dimensioned crossing flangeway on both sides. In a turnout there is a dimensioned crossing flangeway on one side only. (Except in symmetrical 3-throw turnouts and similar, which are for that reason as critical as fixed K-crossings.)

 

So considering the 4-SF dimensions: http://4-SF.uk/dimensions.htm

 

At the tightest limit with the track gauge on 16.2mm MIN the opposite flangeway cannot be more than 1.0mm otherwise the 15.2mm MIN check gauge would be infringed. And the same applies to the other flangeway. But neither flangeway can be less than 1.0mm either, otherwise the 14.2mm MAX check span would be exceeded.

 

So this is a limiting condition, and the only degree of freedom is on the track gauge.

 

Allowing the track gauge to widen, we reach the widest limit at 1.05mm MAX flangeways and 14.2mm MAX check span, so the tack gauge cannot exceed 16.3mm (with the check gauge then at 15.25mm).

 

A satisfactory middle setting, with a small degree of freedom on all dimensions, would be track gauge 16.23mm with 1.02mm flangeways. This then gives a check gauge of 15.21mm and a check span of 14.19mm. Or maybe 16.25mm gauge with 1.03mm flangeways, giving 15.22 check gauge and 14.19mm check span.

 

You can see how the dimensions are inter-related, and quite critical.

 

In practice what you do is to use the gauges as carefully as possible, making the flangeways a nice close, but not tight, fit on the 1.0mm crossing flangeway gauge shim, and checking that the 14.2mm check span has not been exceeded. If you plan to build K-crossings I would suggest getting a digital caliper so that you can check that you are working within the limits given at: http://4-SF.uk/dimensions.htm

 

For 00-BF instead of 4-SF, add 0.3mm to the above dimensions, so that the gauge cannot exceed 16.6mm:

 

track gauge: 16.5mm MIN with 1.3mm flangeways. 1.3mm gauge shim.

crossing flangeway: 1.35mm MAX at 16.6mm gauge.

check gauge 15.2mm MIN (same as 4-SF).

check span: 13.9mm MAX.

and a satisfactory middle setting for fixed K-crossings might be 16.53mm gauge with 1.32mm flangeways, giving 15.21mm check gauge and 13.89mm check span.

 

(00-BF is suitable for RTR wheels only.)

 

For 00-Intermediate, add 0.2mm instead, so that the gauge cannot exceed 16.5mm:

 

track gauge: 16.4mm MIN with 1.2mm flangeways. 1.2mm gauge shim.

crossing flangeway: 1.25mm MAX at 16.5mm gauge.

check gauge 15.2mm MIN (same as 4-SF).

check span: 14.0mm MAX.

and a satisfactory middle setting for fixed K-crossings might be 16.45mm gauge with 1.23mm flangeways, giving 15.22mm check gauge and 13.99mm check span.

 

(00-intermediate is suitable for RTR wheels, and marginally Romford/Markits wheels.)

 

Note that 00-Intermediate differs from DOGA-Intermediate in having a minimum track gauge of 16.4mm, and 15.2mm min check gauge (same as 4-SF and 00-BF, 15.2mm check gauges are available from C&L).

 

regards,

 

Martin.

[polybear]

 

Put another way - does Martin (or anyone else) really fancy marching up to Bath Green Park and telling the group that they shouldn't be working to those standards, that their standard are wrong and should not be countenanced in the hobby, that the layout doesn't work properly, that they have decided those standards should no longer exist or be recognised and the group must accept that etc etc etc?? 

 

Because I don't.

 

 

Mr Siddle,

I may have dreamed it, but didn't a similar situation (not with Martin) happen in the not-to-distance past, many times.......??

I can't quite put my finger on it.....

[polybear]

p.s.

 

According to the CLAG website:

 

http://www.clag.org.uk/swg.html

 

- the thickness of 18 gauge steel is 1.219mm, which sounds rather useful as a Crossing Flangeway Gauge (1.2mm +/-0.05mm).

From the short time I spent Googling the subject I'd suggest the use of a micrometer when selecting a suitable piece though, as it seems that not all 18g materials are the same thickness, and will no doubt vary by supplier (and batch).

If you found 18g Brass or Aluminium then no doubt the thickness could be reduced (if found to be necessary) pretty easily by rubbing on a sheet of fine/very fine wet n' dry, on a flat surface, checking regularly with a mic.

 

Companies such as Coventry Grinders offer a custom service for the supply of Ground Flat Gauge Plate

 

http://www.coventry-grinders.co.uk/faqs/

 

- if only there was a society that represented the needs of 00 modellers then they could investigate supplying 1.2mm Ground Flat Stock for use as Crossing Flangeway Gauges needed when constructing 00 Intermediate Track. 

 

Incidentally, 1mm Gauge Plate is also readily available:

 

http://www.engineeringsupplies.co.uk/gauge-plate-ground-flat-stock-c-193.html?menu=1

 

e.g. 1mm x 10mm wide, 500mm long for £11 delivered; you'd get quite a few gauges out of that....

Useful for 00-sf and also 00 Finescale    

 

HTH

Brian

[hayfield]

Brian

 

Thanks as I have misplaced one of my gauges, so a lot more for just over the cost of 2 C&L ones

[nswgr1855]

Perhaps we should let Terry and Stephen slug it out between them over K-crossings?

 

They will never agree, because the DOGA standards, and AMRA, and NMRA, are all flawed by double-dimensioning.

 

If you look at the 4-SF dimensions: http://4-sf.uk/dimensions.htm

 

you will see that they are all inter-related, each one has a Maximum or a Minimum, but not both.

 

The first thing to say about fixed K-crossings is that they are more critical than turnouts, so beginners should practice on turnouts first, before attempting diamonds and slips. And with wider than scale flangeways they are much more susceptible to mis-tracking than the prototype, so in 00 and EM I would suggest using switch-diamonds instead (movable K-crossings) at angles flatter than about 1:6 (the prototype limit in straight track is 1:8 ). Switch-diamonds are a lot easier to build, less critical, work perfectly, and give the prototype impression of being longer crossings. The only down-side is the need for extra point motors.

 

Getting back to fixed K-crossings, the extra factor to consider is that there is a dimensioned crossing flangeway on both sides. In a turnout there is a dimensioned crossing flangeway on one side only. (Except in symmetrical 3-throw turnouts and similar, which are for that reason as critical as fixed K-crossings.)

 

So considering the 4-SF dimensions: http://4-SF.uk/dimensions.htm

 

At the tightest limit with the track gauge on 16.2mm MIN the opposite flangeway cannot be more than 1.0mm otherwise the 15.2mm MIN check gauge would be infringed. And the same applies to the other flangeway. But neither flangeway can be less than 1.0mm either, otherwise the 14.2mm MAX check span would be exceeded.

 

So this is a limiting condition, and the only degree of freedom is on the track gauge.

 

Allowing the track gauge to widen, we reach the widest limit at 1.05mm MAX flangeways and 14.2mm MAX check span, so the tack gauge cannot exceed 16.3mm (with the check gauge then at 15.25mm).

 

A satisfactory middle setting, with a small degree of freedom on all dimensions, would be track gauge 16.23mm with 1.02mm flangeways. This then gives a check gauge of 15.21mm and a check span of 14.19mm. Or maybe 16.25mm gauge with 1.03mm flangeways, giving 15.22 check gauge and 14.19mm check span.

 

You can see how the dimensions are inter-related, and quite critical.

 

In practice what you do is to use the gauges as carefully as possible, making the flangeways a nice close, but not tight, fit on the 1.0mm crossing flangeway gauge shim, and checking that the 14.2mm check span has not been exceeded. If you plan to build K-crossings I would suggest getting a digital caliper so that you can check that you are working within the limits given at: http://4-SF.uk/dimensions.htm

 

For 00-BF instead of 4-SF, add 0.3mm to the above dimensions, so that the gauge cannot exceed 16.6mm:

 

track gauge: 16.5mm MIN with 1.3mm flangeways. 1.3mm gauge shim.

crossing flangeway: 1.35mm MAX at 16.6mm gauge.

check gauge 15.2mm MIN (same as 4-SF).

check span: 13.9mm MAX.

and a satisfactory middle setting for fixed K-crossings might be 16.53mm gauge with 1.32mm flangeways, giving 15.21mm check gauge and 13.89mm check span.

 

(00-BF is suitable for RTR wheels only.)

 

For 00-Intermediate, add 0.2mm instead, so that the gauge cannot exceed 16.5mm:

 

track gauge: 16.4mm MIN with 1.2mm flangeways. 1.2mm gauge shim.

crossing flangeway: 1.25mm MAX at 16.5mm gauge.

check gauge 15.2mm MIN (same as 4-SF).

check span: 14.0mm MAX.

and a satisfactory middle setting for fixed K-crossings might be 16.45mm gauge with 1.23mm flangeways, giving 15.22mm check gauge and 13.99mm check span.

 

(00-intermediate is suitable for RTR wheels, and marginally Romford/Markits wheels.)

 

Note that 00-Intermediate differs from DOGA-Intermediate in having a minimum track gauge of 16.4mm, and 15.2mm min check gauge (same as 4-SF and 00-BF, 15.2mm check gauges are available from C&L).

 

regards,

 

Martin.

 

Hello Martin,

 

I disagree with you about your general comment about the AMRA standards in your opening comment.

 

There is no double-dimensioning in the AMRA standards. The 'apparent' double dimensioning in the AMRA standard is between the standards limits and the standards 'recommended limits' for crossing V's and K's and wheel flange profile. The AMRA standard is the only standard that recommends to the model builder the correct limits for K crossings.

 

Your alternative dimensions also seem to have the same problem as the DOGA  standard when it comes to K crossings, the maximum span is optimistically small, but why bother, continue to use the 00-SF limits = AMRA fine tolerance standard except for the maximum span (check face to check face dimension and minimum wheel back to back) if building you own track.  The problem is the original EM 18.2mm standard has the same error. You need to do the sums from start to get it right. 

 

Cheers,

 

Terry Flynn

[Ravenser]

Hello Martin,

 

I disagree with you about your general comment about the AMRA standards in your opening comment.

 

There is no double-dimensioning in the AMRA standards. The 'apparent' double dimensioning in the AMRA standard is between the standards limits and the standards 'recommended limits' for crossing V's and K's and wheel flange profile. The AMRA standard is the only standard that recommends to the model builder the correct limits for K crossings.

 

Your alternative dimensions also seem to have the same problem as the DOGA  standard when it comes to K crossings, the maximum span is optimistically small, but why bother, continue to use the 00-SF limits = AMRA fine tolerance standard except for the maximum span (check face to check face dimension and minimum wheel back to back) if building you own track.  The problem is the original EM 18.2mm standard has the same error. You need to do the sums from start to get it right. 

 

Cheers,

 

Terry Flynn

 

You seem to be arguing that EM gauge doesn't work either....

 

I think I can be regarded as a neutral when it comes to EM gauge, but the simple fact is that quite a few large EM layouts have been built over the last 70 years and many of them have been exhibited. Claims that complex pointwork can't be built satisfactorily in EM won't hold water when folk can go to shows, see EM layouts with such pointwork for themselves and judge the running. Layouts where the stock keeps falling off don't get a good name on the circuit......

 

 

(There's probably some fairly complex pointwork in the final version of Buckingham, and wasn't Tone Vale EM as well? I don't seem to have a photo of Wibdenshaw on file , but it's a big layout with a large station and a fairly complex throat. And so forth - there's enough examples out there with their running very publicly visible through a big 2 day show to torpedo any claim that "it won't work" in EM)

 

In the meantime , we have another OO standards issue to contemplate:

 

http://www.rmweb.co.uk/community/index.php?/topic/33331-kernow-adams-o2/page-31

http://www.rmweb.co.uk/community/index.php?/topic/33331-kernow-adams-o2/page-32

 

The full gory details may require wading through a few pages on either side, but in essence the Kernow/DJM O2 0-4-4Ts have arrived and it seems they have been produced with a fixed bogie pivot - to compensate for which, and to lower the minimum radius, the model has been produced with B2Bs of at least 15mm - values of 15.2mm have been reported on the front drivers and rear pony wheels of some models. The idea appears to be that a thin chassis block and an unusually wide B2B will give very substantial sideplay on the wheelset to get the model round tight curves.

 

Since the driving wheels are connected by gearing, substantial sideplay here raises an obvious question about the effect on the gears in the drivetrain

 

However - more pertinently in this thread - a B2B of 15.0mm-15.2mm has obvious implications for the effectiveness of the checkrails on track to any known track standard , and especially on Peco Streamline with its 1.39mm flangeways (The words "chocolate fireguard" spring to mind) 

 

It seems the factory has delivered distinctly variable B2Bs on the actual models , with variations of 0.2-0.3mm in B2B between different examples. The Chinese factories, used to working with 14.4mm , probably find themselves in very unfamiliar territory with all of this.

 

Models with the B2B pushed as high as 15.2mm are reportedly displaying binding on 2' radius curves - an issue reported in the Model Rail review by Chris Leigh. 

 

Needless to say none of this complies with any wheel standard devised by anyone for any flavour of 4mm standard gauge.

 

It seems the manufacturers feel "it works just fine".

 

At this point you may find it prudent to interpose a large soft object like a pillow between your head and the nearest brick wall.....

[hayfield]

And its been so quiet for the past week!! 

[nswgr1855]

You seem to be arguing that EM gauge doesn't work either....

 

I think I can be regarded as a neutral when it comes to EM gauge, but the simple fact is that quite a few large EM layouts have been built over the last 70 years and many of them have been exhibited. Claims that complex pointwork can't be built satisfactorily in EM won't hold water when folk can go to shows, see EM layouts with such pointwork for themselves and judge the running. Layouts where the stock keeps falling off don't get a good name on the circuit......

 

Ally Pally2012 (6) 1024x768.JPG

 

(There's probably some fairly complex pointwork in the final version of Buckingham, and wasn't Tone Vale EM as well? I don't seem to have a photo of Wibdenshaw on file , but it's a big layout with a large station and a fairly complex throat. And so forth - there's enough examples out there with their running very publicly visible through a big 2 day show to torpedo any claim that "it won't work" in EM)

 

 

 

 

I am talking about the standard from the 1970's not adding up. I am not a member of the EM gauge society, so I do not have a copy of the current standard, however if you want to know what does add up have a look at the AMRA fine tolerance standard http://www.amra.asn.au/standards.htm. Showing me examples of lovely working layouts built to EM gauge does not mean the layouts comply fully with the EM gauge standard from the 1970's. I have seen a number of derailment free EM gauge layouts in the flesh, both in the UK and Australia. No doubt they have used EM gauge society track gauges, so there will not be a compatibility issue between EM gauge layouts even if they technically do not comply fully with the standard. 

 

Cheers,

 

Terry Flynn. 

[Grovenor]

In the meantime , we have another OO standards issue to contemplate:

 

http://www.rmweb.co....dams-o2/page-31

http://www.rmweb.co....dams-o2/page-32

 

The full gory details may require wading through a few pages on either side, but in essence the Kernow/DJM O2 0-4-4Ts have arrived and it seems they have been produced with a fixed bogie pivot - to compensate for which, and to lower the minimum radius, the model has been produced with B2Bs of at least 15mm - values of 15.2mm have been reported on the front drivers and rear pony wheels of some models. The idea appears to be that a thin chassis block and an unusually wide B2B will give very substantial sideplay on the wheelset to get the model round tight curves.

 

Firstly this is not a standards issue but a loco design and build quality issue. The reported problems have been cured by those who have reset the Back to back to the standard value. 

Secondly, the side play available for negotiating curves is the sum of the play of the wheelset between the rails and the play of the wheelset in the chassis. Increasing the back to back just takes away from the first to add to the second with no change to the total sideplay available.

The reported lifting of the front drivers under load is an inevitable result from attempting to use a rigid chassis for an 0-4-4. it could have easily been avoided by using a rocking frame for the drivers as Heljan did with their Garratt.

Regards

[Izzy]

http://www.rmweb.co.uk/community/index.php?/topic/33331-kernow-adams-o2/page-31

http://www.rmweb.co.uk/community/index.php?/topic/33331-kernow-adams-o2/page-32

 

The full gory details may require wading through a few pages on either side, but in essence the Kernow/DJM O2 0-4-4Ts have arrived and it seems they have been produced with a fixed bogie pivot - to compensate for which, and to lower the minimum radius, the model has been produced with B2Bs of at least 15mm - values of 15.2mm have been reported on the front drivers and rear pony wheels of some models. The idea appears to be that a thin chassis block and an unusually wide B2B will give very substantial sideplay on the wheelset to get the model round tight curves.

 

Since the driving wheels are connected by gearing, substantial sideplay here raises an obvious question about the effect on the gears in the drivetrain

 

However - more pertinently in this thread - a B2B of 15.0mm-15.2mm has obvious implications for the effectiveness of the checkrails on track to any known track standard , and especially on Peco Streamline with its 1.39mm flangeways (The words "chocolate fireguard" spring to mind) 

 

It seems the factory has delivered distinctly variable B2Bs on the actual models , with variations of 0.2-0.3mm in B2B between different examples. The Chinese factories, used to working with 14.4mm , probably find themselves in very unfamiliar territory with all of this.

 

Models with the B2B pushed as high as 15.2mm are reportedly displaying binding on 2' radius curves - an issue reported in the Model Rail review by Chris Leigh. 

 

Needless to say none of this complies with any wheel standard devised by anyone for any flavour of 4mm standard gauge.

 

It seems the manufacturers feel "it works just fine".

 

At this point you may find it prudent to interpose a large soft object like a pillow between your head and the nearest brick wall.....

 

I think, if you read the thread as I have done, you will find that the issue is not one of changed standards, but rather just QC problems, wheels not being fully pushed home to the correct b-t-b on some models, rather than a deliberate attempt to use modified standards. There are some concerns about traversing tighter radius curves and hauledge, but these seem to revolve around the use of a sprung fixed point bogie allowing the front drivers to loose traction. You appear to be reading something into the problems that doesn't exist as far as I can see, but perhaps I'm missing something

 

Perhaps more to the point, increasing the b-t-b of a wheelset alone won't bring any benefit as regards increased sideplay, because it is usually offset by an equal reduction in tread sideplay, so one cancels out the other. Only by reducing the flange thickness and either keeping the same b-t-b or increasing it by the amount of reduction in flange width, will bring a benefit as regards increased sideplay over that which can normally be found/produced by careful adjustment of the basic chassis width in relation to the particular loco and it's axle wheelbase. Increased sideplay on the driven axles shouldn't have any bearing on the gear train if, as one would expect, it is composed of a spur gear train following initial worm wheel gear reduction, as is now commonly used in much r-t-r locos.

 

These are of course just general observations. Each particular loco/build/model will vary. Same as Grovenor has said,  probably better, and just beat me to it.

 

Izzy

[martin_wynne]

Increasing the back-to-back may or may not affect sideplay and running on curves.

 

But it will cause the wheels to derail on pointwork, so as a solution to anything it is not the brightest idea.

 

Martin.

[Buhar]

I haven't built track since an early seventies brief foray into P4.  Rivetted sleepers and file your own vees!  Where I am now is deciding whether I will be helped by building some points to free myself from Peco's geometry at a couple of locations.  

 

All my current points are Peco Electrofrog Code 75 (medium radius as a minimum) with C&L plain track.  I run modern RTR steam locos from both Hornby and Bachmann, (with some examples of their earlier work too).  Plus some kits that have wheels from Markits and Alan Gibson (00 type) and I think there's set of Romfords under something as well.   Rolling stock is re-wheeled if plastic, otherwise left as is.  I've got two or three B2Bs (which I haven't run calipers over assuming they would be the same) and tended to use whichever I came across when checking stock.

 

Apart from an ancient Ks Kirtley 0-6-0 (where I blame my early chassis skills) everything ran OK (the past tense is because the layout is currently in storage).  I always had problems with B2Bs on Gibson's which may be down to needing a wider B2B as noted above. I've ended up using trial and adjust with a feeler gauge held on the B2B, but never understood why.

 

Despite assertions that appear to indicate Gibson's won't negotiate Peco Code 75s, mine did (eventually) and it appears from other layouts on here that that's not unique.

 

Wheels and mechanisms are expensive components and I would rather build my couple or three points to fit what I'm currently using rather than create a lovely looking piece of track that leads onto an expensive re-wheeling exercise.  I also have something that works, which seems a good starting point.

 

I don't care what the standards are called (00- Abigail, 00-Barney, 00-Clodagh) I just want to know whether a particular set is are compatible with the wheels there are around.  Then I want to know which gauges I should be using to maintain my chosen set.

 

DOGA (or someone) could produce a simple table, maybe with footnotes to indicate those components that should work but don't and those that shouldn't work but do.

 

In the meantime, which standard should I go with for these 'ere points.

 

BTW, Terry, is a K-crossing the diamond in a double junction?

[martin_wynne]

Despite assertions that appear to indicate Gibson's won't negotiate Peco Code 75s, mine did (eventually) and it appears from other layouts on here that that's not unique.

....

 

BTW, Terry, is a K-crossing the diamond in a double junction?

 

Hi Alan,

 

"Negotiate" is a rather imprecise term.

 

They will certainly run through them if the back-to-back is adjusted accordingly. But in the process they will drop into the crossings (frogs) with a bump.

 

If you happy with that quality of running, you should go for 00-BF or 00-BRMSB, for maximum tolerance of variable back-to-backs.

 

If you prefer wheels to remain fully supported on the rails when running through crossings, in the prototype fashion, you should go for 4-SF (00-SF). But in doing so you must be prepared to check back-to-backs for compliance (14.6mm for Alan Gibson/Ultrascale, 14.5mm for Romford/Markits, 14.4mm for RTR wheels). And not expect to use sharp train-set radii below about 750mm / 30" radius for the running lines.

 

This is a K-crossing. There are 2 of them in the middle of a diamond-crossing.

 

 

regards,

 

Martin.