New products for 00-SF -- and 5 pages of silly arguments about it

[martin_wynne]

Either by rail joint misalignments, struck by the narrower finer flange edges, or by the sheer tightness of the gauge, due to the finer 00/HO wheels necessary wider B-B.

 

Andy,

 

The finer wheels DO NOT need a wider back-to-back.

 

You are mixing up DOGA Fine with 00-SF and causing great confusion and worry to beginners where there is none.

 

00-SF started life as "EM minus 2". All I did was change the name designation for Templot.

 

EM gauge has been working fine for 50 years, and all we are doing in 00-SF is reducing everything by 2mm. If you use "finer wheels", i.e. the same ones as EM, they work just as well in 00-SF as in EM. The back-to-back is reduced by the same amount, 2mm, from 16.5mm to 14.5mm. There is exactly the same gauge freedom in 00-SF as in EM. All that is necessary is for 00-SF modellers to use the same radius limits as in EM.

 

Martin.

[Andy Reichert]

No confusion ???

 

This isn't my doing.  It seems someone else thinks 00, HO and 00-SF are the same and fully interchangeable.  Or the former don't matter?

 

 

 

The measured gauge of these units is 16.2 mm. (amazing co-incidence?)

 

Absolutely useless for anyone needing rollers for 16.5 mm "00" or HO gage and using properly set back to back, fine scale wheels.   As I stated in my post "FINER" scale wheels can get squeezed up out of the track by too narrow a gauge. These correct for 16.5 mm gauge wheels don't even drop down into the rollers.

 

This what happens when design is done to meet "Gosh - Look it works fine for typical RTR vehicles values" and then built to "just" fit those, instead of using the proven "full interchangeability, including possible worst-case" published documentation of the internationally recognised 00 an HO standards.

 

The physical difference is huge and the product useless for the purpose for which it advertised and bought. But the methodology is the same as the reasoning for the existence of 00-SF. It matches only the SUB-SET of CURRENT RTR product dimensions, and any other past and (MORE LIKELY) FUTURE developments are not supported.

Yet this product is absolutely confusingly clearly labeled as "00" and "HO and 16.5 mm.

 

Andy
 

[Grovenor]

Since those are just pairs of roller units pushed into a plastic sleeve can you not just pull them out a bit and set the gauge as you want it?

Keith

PS. I entirely agree they should be 16.5 in the first place, but ----

[martin_wynne]

    Andy Reichert, on 23 Mar 2014 - 16:12, said:

As I stated in my post "FINER" scale wheels can get squeezed up out of the track by too narrow a gauge. These correct for 16.5 mm gauge wheels don't even drop down into the rollers

 

Hi Andy,

But it's not true. What do you mean by "properly set back to back, fine scale wheels" ?

For RP25/88 / EMGS wheels the flange thickness is 0.7mm and the back-to-back is 14.5mm max. So across both flanges is 15.9mm max, and they run just fine on 16.2mm gauge.

For RP25/100 Markits-Romford wheels the flange thickness is 0.75 mm and the back-to-back is 14.5mm max. So across both flanges is 16.0mm max, and they run just fine on 16.2mm gauge.

For RP25/110 RTR wheels the flange thickness is 0.8 mm and the back-to-back is 14.4mm*. So across both flanges is 16.0mm, and they run just fine on 16.2mm gauge. See: http://www.doubleogauge.com/standards/commercialwheels.htm

Some Ultrascale wheels have flanges 0.6mm thick. They can be set to 14.6mm max back-to-back if desired, so across both flanges is 15.8mm, and they run just fine on 16.2mm gauge.

I think you are getting confused with the DOGA Fine 00 standard, which has no relevance to this topic and which requires modified back-to-backs. We are not discussing DOGA Fine here.

   

instead of using the proven "full interchangeability, including possible worst-case" published documentation of the internationally recognised 00 an HO standards.

 

 

For the umpteenth time of saying so, 00-SF is not proposed as a commercial standard for the model trade. It is intended as a track option for modellers to use in the privacy of their own workshop and on their own railway, if they so choose. In the event that they find they have a "possible worst-case" wheel, they will adjust or replace it -- we are talking about practical modelmakers here. Those who have tried 00-SF are very pleased with the results, but they are not suggesting that the rest of world should do the same if they don't want to, or even take the slightest notice.

*14.4mm max is the old "proper" NMRA dimension based on prototype methods of dimensioning. A few years ago NMRA changed to a daft "targeted" system of dimensions, and the tables now contain numerous anomalies and inconsistencies. Fortunately I think most manufacturers are still using tooling and assembly jigs based on the original dimensions.

Martin.

 

[Grovenor]

There is a lot of misunderstanding going on here, Martin, I'm sure you are well aware that Andy runs the P87 stores, that P87 uses 16.5mm track and that Andy is making the simple point that the rollers he purchased which clearly state that they are 16.5 in fact are not. Since he requires 16.5 and not 16.2 he has the choice of taking the matter up with DCC concepts or fixing it himself. The manufacturer concerned here has clearly not managed to build his rollers to the "original dimensions" even though they claim to be.

Keith

[martin_wynne]

There is a lot of misunderstanding going on here, Martin, I'm sure you are well aware that Andy runs the P87 stores, that P87 uses 16.5mm track and that Andy is making the simple point that the rollers he purchased which clearly state that they are 16.5 in fact are not.

 

Sure, but why is he posting about them in this topic about new 00-SF products for the UK market? If he has purchased a faulty product for P-87, the obvious thing would be to send it back, or post about it in a P-87 topic. Posting about it in a topic about 00-SF doesn't help anyone. Everyone knows P-87 wheels won't run on 00-SF, and no-one has ever suggested otherwise.

 

There are a lot of 00 modellers interested in these new 00-SF products, no doubt being utterly confused by some off-topic posts here.

 

Martin.

[Ravenser]

As a point of record OO rolling stock wheelsets sold by Gibson are set to either a 14.7mm or 14.8mm back to back. If you want these values to be 14.5mm , you'll have to close up the wheels around a suitable brass B2B gauge .  

 

Steam locomotive driving wheels are obviously sold singly, and the back to back will be set by the builder according to his B2B gauge. The same applies to the Ultrascale rewheeling packs I've seen

[martin_wynne]

As a point of record OO rolling stock wheelsets sold by Gibson are set to either a 14.7mm or 14.8mm back to back

 

Presumably they are labelled for DOGA Fine? The traditional BRMSB back-to-back for 00 has always been 14.5mm.

 

However, the critical dimension is the 15.2mm max back-to-flange dimension, so the optimum back-to-back will depend on the flange thickness.

 

 

Steam locomotive driving wheels are obviously sold singly, and the back to back will be set by the builder according to his B2B gauge.

 

Markits (Romford) wheels fit matching supplied axles with squared ends for quartering. They are quoted 14.5mm back-to-back for 00, and 16.5mm back-to-back for EM.

 

Martin.

[trustytrev]

Maths Alert (I like to approximate 1mm as 0.040").

 

NMRA reference link: http://www.nmra.org/standards/sandrp/pdf/S-3.2%202010.02.24.pdf

 

For those that can decipher the NMRA standards, the turnout flangeways are surprisingly asymmetrical, at gauge min (16.5 mm). I.e. With the check gauge at max., the check rail gap is somewhere around only 0.035" (0.9 mm) if the crossing flange way is set at 0.050" (1.25 mm).  Note however that even the NMRA crossing flangeway min is allowed to be as small as 0.035" (also 0.9mm), although one has to be careful not to break any of the other dimensions if taking it that low..

 

The unfortunate situation with many past US RTR turnouts is that they mistakenly widened the gauge at the crossings, to make the check flangeways seem more symmetrical, particularly as the then NMRA standards gave the gauge max as a top tolerance, rather than indicating it was only for gauge widening on curves.

 

The (really!) good news for finer flangeway lovers, is that you can merely move the crossing flangeway inwards, to make it much closer, while at the same time increasing the check flangeway to balance, so the span is not compromised, and still not need to reduce the gauge below 16.5 mm. That's often quite simple and straightforward to do to existing, even laid, hand built and RTR turnouts.

 

 

Here is a quick scan of a recent Peco US code 83 crossing. I get a consistent 0.650" for the gauge, and what seems to be somewhat reduced flangeways as per above, although it's getting a bit late to hold my dial caliper steady to be certain of the gaps sizes. Maybe one of you can measure off the picture?

 

Off the top of my head, I think a symmetrical 0.044" ( 1.1 mm) is perfectly easy, and my old friends at Central Valley I KNOW have their whole huge NWP layout built with 0.40" (1 mm) crossings, and whatever check flangeway that works out as, while still keeping to 16.5 mm for their track gauge, and yet using completely smooth running "finescale" wheels of their own manufacture on most of their cars.

 

I am just now being called for kitchen chores by my own dear SWMBO, so will not stay do the maths for everyone here at this time. But hopefully, someone else will.

 

TIA

 

Andy

Hello,

        Why is someone clearly into HO/3.5mm scale making such a vociferous objection to 00sf hand built track. As far as I am aware 00sf is a pragmatic approach for modellers in British 4mm scale to achieve more realistic track for running 00 gauge models(Another British quirk)on, rather than the current commercially available H0 products which happen to use a similar gauge.

As far as I am aware no one(NO ONE) produces a suitable commercial product to achieve that end.

Troll is a word that springs to mind whilst reading this thread and I am surprised moderation has not been exercised.

I am extremely grateful to those whom have made that alternative possible.

trustytrev.

[bill badger]

If only all the 'energy' that this type of topc generates in people could be diverted in some way to making the world a better place...

 

Anyway, my order for a set of OO-SF gauges should be delivered in the next couple of days. Thanks to the folk who highlighted their availability from C&L. Here's to getting some trackwork built... 

 

On the subject of back to backs, I've been wielding my vernier on a few suspects: all my Bachmann stock came in at 14.4mm or 14.5mm. Romofrd axles on my various PD wagons kits were the same. The few Gibson wagon axles I have used were 14.7mm. Most surprisingly were my two Hornby models, an old L&Y pug and a brand new LMS CCT van, that both come in at 14.2mm. I would have thought its always worth checking, no matter what track you buy or build. I'll be interested to see how the Gibson wheeled wagons and the two Hornby models run through the business section of turnouts built to OO-SF.

[gordon s]

00 Finescale wheels are unlikely to be of any interest to those of us building OO-SF pointwork, so really don't add anything to this discussion.  The closest I run to 'Finescale' are Ultrascales and they work really well, particularly the fact that their narrow treads don't drop into the hole between the crossing vee and the wing rail.  The wheel is totally supported all the way through and I have close up pics to show that.

 

Having said all that, curiosity got the better of me regarding your post and pics, Andy, so I looked up the 00 Finescale wheel standards.  As expected I found two specs that basically agreed but were slightly different.  The first gave the B2B as 14.8mm min, the second 14.7-14.9mm.  With regard to the wheel flange, one said 0.686mm and the other 0.7mm.  OK, humour me for a minute.

 

Looking at your pic of the rollers, I can't see why the wheel is sitting on top of one of the rollers if the gauge is 16.2mm and the B2B's a max of 16.3mm

 

Worst case outer flange to outer flange would be 14.9mm + (2 x 0.7mm) = 16.3mm, just 0.1mm outside the 16.2mm gauge for 00-SF.  From your pic, either the roller is less than 16.2mm wide or the B2B of the wheels must be greater than 16.3mm judging by the overlap of the wheel to the roller.

 

Perhaps it's just an optical illusion, but it certainly looks more than 0.1mm.

 

Of course all this is academic.  I'm not using 00 Finescale wheels and neither does any of my stock.  I chose 00-SF as I'm running Hornby, Bachmann, Atlas, Athearn Genesis, Walthers, Tower55, Overland, MTH, Fleischmann, Heljan, Romfords, Markits and Ultrascales, all of which run perfectly through my 00-SF pointwork without any change to B2B's.  The one exception I will accept, is possibly Heljan where I have seen one or two of their locos with B2B's of less than 16.2mm.  I only have a few Heljan locos, so it really is just one or two out of 200 locos of various manufacture and not an issue at all.

[martin_wynne]

Having said all that, curiosity got the better of me regarding your post and pics, Andy, so I looked up the 00 Finescale wheel standards.

 

Hi Gordon,

 

Andy's pics show Proto-87 wheels, not 00 wheels. Proto-87 is the 3.5mm/ft equivalent of P4 -- see Andy's site: http://www.proto87.com

 

Proto-87 wheels require 16.5mm track gauge and won't run on 00-SF, nor on any other 00 standard.

 

His pictures and dimensions have no relevance to this 00-SF topic at all.

 

Andy, there is masses of stuff to read about 00-SF on RMweb -- I've written a lot of it myself, most of it several times over.  

 

regards,

 

Martin.

[Andy Reichert]

Hello,

        Why is someone clearly into HO/3.5mm scale making such a vociferous objection to 00sf hand built track. As far as I am aware 00sf is a pragmatic approach for modellers in British 4mm scale to achieve more realistic track for running 00 gauge models(Another British quirk)on, rather than the current commercially available H0 products which happen to use a similar gauge.

 

SNIP

 

trustytrev.

 

Please see my under construction layout: I'm as interested in having good looking and reliable 4mm running on "true" 00 gauge as much as anyone here.

 

 

 

I'm proud to have grown up as a railway, tube and trolley-bus travelling  East Londoner.  Kits of Quint-Arts, N7's and 306's and 305's are awaiting their time on the workbench.

 

 

Here's also a picture of the comparative visual improvement to tube stock with fine scale wheels that can run on 16.5 mm gauge.

 

Andy

[gordon s]

Thanks Martin…and Andy for your next post.  I really like your pics of finescale tube stock wheels and perhaps 00-SF is not the right product for you. It's a no brainer for your wheel choice and if I were running wheels of that standard in H0 then I would agree with you.  For those of us who dabble in hand built track and RTR stock with no mods, 00-SF will do just fine.

 

What's really confusing me though is running UK stock with finescale wheels on 00 gauge track.  If you have followed your Proto 87 ideals in H0, then surely all your UK stock would be in P4?  Why compromise?

 

If it's a requirement to run your UK stock on a Proto 87 layout, then surely you're making a personal choice and it's nothing to do with standards.  I'm building a UK based layout, yet you will note I have numerous US loco's.  Why?

 

I travelled a lot on business and often found myself in far flung places with a few hours to kill.  Naturally I looked for the nearest model shop and came out with odd ball loco's that had nothing to do with BR (ER) in the 60's.  

 

Life's like that, but I wouldn't confuse a discussion on Proto 87 with my own choice of stock in UK 4mm…:-)

[martin_wynne]

Here's also a picture of the comparative visual improvement to tube stock with fine scale wheels that can run on 16.5 mm gauge.

 

 

But Andy those are Proto-87 wheels. Yes they run on 16.5mm gauge track, but they won't run through any known 00 gauge pointwork.

 

Here are the Proto87 standards: http://www.proto87.org/d/?q=node/6

 

The required flangeway gap is only 0.6mm. No-one uses such narrow flangeways in 00 gauge. Many 00 wheels have thicker flanges than that.

 

So the relevance to this discussion about 00-SF is difficult to understand. You know well that here in the UK anyone wanting to use such fine wheels in 4mm/ft scale will be modelling in P4, not 00.

 

regards,

 

Martin.

[hayfield]

00 Finescale wheels are unlikely to be of any interest to those of us building OO-SF pointwork, so really don't add anything to this discussion.  The closest I run to 'Finescale' are Ultrascales and they work really well, particularly the fact that their narrow treads don't drop into the hole between the crossing vee and the wing rail.  The wheel is totally supported all the way through and I have close up pics to show that.

 

Having said all that, curiosity got the better of me regarding your post and pics, Andy, so I looked up the 00 Finescale wheel standards.  As expected I found two specs that basically agreed but were slightly different.  The first gave the B2B as 14.8mm min, the second 14.7-14.9mm.  With regard to the wheel flange, one said 0.686mm and the other 0.7mm.  OK, humour me for a minute.

 

Looking at your pic of the rollers, I can't see why the wheel is sitting on top of one of the rollers if the gauge is 16.2mm and the B2B's a max of 16.3mm

 

Worst case outer flange to outer flange would be 14.9mm + (2 x 0.7mm) = 16.3mm, just 0.1mm outside the 16.2mm gauge for 00-SF.  From your pic, either the roller is less than 16.2mm wide or the B2B of the wheels must be greater than 16.3mm judging by the overlap of the wheel to the roller.

 

Perhaps it's just an optical illusion, but it certainly looks more than 0.1mm.

 

Of course all this is academic.  I'm not using 00 Finescale wheels and neither does any of my stock.  I chose 00-SF as I'm running Hornby, Bachmann, Atlas, Athearn Genesis, Walthers, Tower55, Overland, MTH, Fleischmann, Heljan, Romfords, Markits and Ultrascales, all of which run perfectly through my 00-SF pointwork without any change to B2B's.  The one exception I will accept, is possibly Heljan where I have seen one or two of their locos with B2B's of less than 16.2mm.  I only have a few Heljan locos, so it really is just one or two out of 200 locos of various manufacture and not an issue at all.

 

 

Gordon

 

No wonder we all either get confused or misunderstand each other. Your statement about 00 finescale wheels could be confusing. Many of us build the odd kit wagon or coach, and quite a few of these kits come with what I would call 00 gauge finescale wheels (Maygib, Gibson, Slaters etc), these do seem to work through 00-sf without any problems at all, just running through a set of Gibson ones on a wagon now

[Andy Reichert]

SNIP

 

What's really confusing me though is running UK stock with finescale wheels on 00 gauge track.  If you have followed your Proto 87 ideals in H0, then surely all your UK stock would be in P4?  Why compromise?

 

If it's a requirement to run your UK stock on a Proto 87 layout, then surely you're making a personal choice and it's nothing to do with standards.  I'm building a UK based layout, yet you will note I have numerous US loco's.  Why?

 

 I'm now joining the great mass of the "retired". So I'm assuming that only have time for one layout and it will have to combine my interests in UK nostalgia and the few electrified US railways. It's pre-retirement purpose was also to be the definitive "proof of concept" for US Proto:87, by demonstrating P:87 running successfully over the full extent of the specification limits, including full prototype speeds and long train lengths/weights.

 

That last process is almost complete, as a quick visit to RM WEB "Overseas Modelling" will confirm.

 

FYI, the trackwork I use is accomodates P4 wheel profiles as well as P:87, so I have the choice as far as UK outine is concerned, provided I adjust the former wheelsets to P:87 B-B. BTW, note I understand traditional P4 wheels are made 0.08" wide, when their scale size suggests they should be only 0.072" wide. So using appropriate diameter P:87 wheels ( 0.064" wide) under UK stock is actually only the same size error as using P4 wheels.

 

Andy

[Budgie]

I'm getting really fed up with this argument, and I wish it would stop.

 

Incidentally, when I grew up, tube trains were 7 cars long, except for the Ongar line which were 4 cars. So why is yours (as shown in that video) 3 cars?

[gordon s]

Gordon

 

No wonder we all either get confused or misunderstand each other. Your statement about 00 finescale wheels could be confusing. Many of us build the odd kit wagon or coach, and quite a few of these kits come with what I would call 00 gauge finescale wheels (Maygib, Gibson, Slaters etc), these do seem to work through 00-sf without any problems at all, just running through a set of Gibson ones on a wagon now

 

I take your point John, but the discussion somehow got onto an unknown to me, DOGA 'Finescale' standard and doing the possible maths showed it may be possible to have a set of wheels that could have in a worst case scenario, a need for track with a minimum of 16.3mm gauge.  Like you, I had looked at 'finescale' before, but all the wheels I had seen had a B2B of less than 14.8mm, so that was a new one on me.  It is extremely unlikely anyone who is building track in 00-SF would even consider wheels of that standard, so a real red herring to the topic.  Anyone who wanted wheels to that standard would be building in P4 anyway.  

 

It reminded me a bit of my other passion for fast cars and those guys who build a kit version of a Ferrari 250GTO and then put it on a Mondeo chassis.:-)

 

Of course the whole subject of Proto 87 is totally irrelevant to 00-SF, but as I said my curiosity that stemmed from Andy's pics got the better of me.

 

We've all said this dozens of times and those of us who have crossed over to the dark side know this to be true. 00-SF will allow you to run most, if not all modern RTR stock and finescale wheels from Romford, Markits, Ultarscale etc without adjusting B2B's.  You may get the odd loco from Heljan that has a B2B of less than 14.2mm, but they are very much the exception.

 

My own stock from Hornby, Bachmann, Heljan, Fiatrains, Golden Age, Atlas, Athearn Genesis (do I really have to list them all?) will run through 00-SF pointwork without any B2B modification.  Period.

 

Apologies if you feel this clouded the issue.  Pure curiosity got the better of me...

[Andy Reichert]

I'm getting really fed up with this argument, and I wish it would stop.

 

Incidentally, when I grew up, tube trains were 7 cars long, except for the Ongar line which were 4 cars. So why is yours (as shown in that video) 3 cars?

 

It's not a train yet, just three out of the seven cars sitting on the track as motivation for making progress. It's the wrong stock for the London to Epping trip. Fortunately, despite being of tender age, I was able to make that trip and see the old Epping-Ongar steam push-pull set before it was replaced. And (joy ,joy. . .) go for a ride in the London Country GS waiting outside the station.

 

Andy

[Ravenser]

If only all the 'energy' that this type of topc generates in people could be diverted in some way to making the world a better place...

 

Anyway, my order for a set of OO-SF gauges should be delivered in the next couple of days. Thanks to the folk who highlighted their availability from C&L. Here's to getting some trackwork built... 

 

On the subject of back to backs, I've been wielding my vernier on a few suspects: all my Bachmann stock came in at 14.4mm or 14.5mm. Romofrd axles on my various PD wagons kits were the same. The few Gibson wagon axles I have used were 14.7mm. Most surprisingly were my two Hornby models, an old L&Y pug and a brand new LMS CCT van, that both come in at 14.2mm. I would have thought its always worth checking, no matter what track you buy or build. I'll be interested to see how the Gibson wheeled wagons and the two Hornby models run through the business section of turnouts built to OO-SF.

 

Completely unsurprised - exactly what I'd expect and matches my own experiences as a OO modeller.

 

I discovered years ago that it's imperative to check the facts on the ground and not rely on what you'd always been told was true by someone . It's startling what crawls out when you start lifting stones with your dial calipers in hand

 

Normally Hornby locos are 14.4mm, and when Sandakan were making them they were very consistant. But they went through a brief phase of 14.1mm and 14.2mm on locos around 2000-2.  Bachmann could vary between 14.3mm and 14,5mm on the same loco 

[hayfield]

I take your point John, but the discussion somehow got onto an unknown to me, DOGA 'Finescale' standard and doing the possible maths showed it may be possible to have a set of wheels that could have in a worst case scenario, a need for track with a minimum of 16.3mm gauge.  Like you, I had looked at 'finescale' before, but all the wheels I had seen had a B2B of less than 14.8mm, so that was a new one on me.  It is extremely unlikely anyone who is building track in 00-SF would even consider wheels of that standard, so a real red herring to the topic.  Anyone who wanted wheels to that standard would be building in P4 anyway.  

 

It reminded me a bit of my other passion for fast cars and those guys who build a kit version of a Ferrari 250GTO and then put it on a Mondeo chassis.:-)

 

Of course the whole subject of Proto 87 is totally irrelevant to 00-SF, but as I said my curiosity that stemmed from Andy's pics got the better of me.

 

We've all said this dozens of times and those of us who have crossed over to the dark side know this to be true. 00-SF will allow you to run most, if not all modern RTR stock and finescale wheels from Romford, Markits, Ultarscale etc without adjusting B2B's.  You may get the odd loco from Heljan that has a B2B of less than 14.2mm, but they are very much the exception.

 

My own stock from Hornby, Bachmann, Heljan, Fiatrains, Golden Age, Atlas, Athearn Genesis (do I really have to list them all?) will run through 00-SF pointwork without any B2B modification.  Period.

 

Apologies if you feel this clouded the issue.  Pure curiosity got the better of me...

 

 

Ah CARS

 

My boss used to drive me home each day from the West End up the Finchley Road, he had a Jag at the time. Anyway he wanted a Porche so quite often whilst he was trying to find one we would stop and go into the show rooms, I would wonder over to the Lamborghinis  and look at the £100k + cars. Anyway driving up the Finchley Road every night and mornings) super cars would go by or we would pass them, and every now and then he would say kit car. Looking at the kit car mags it seemed that most were based on the VW Beetle chassis. Well seeing someone in a red Ferrari (wearing red braces) or some bright colour Lamborghini thinking is it a Beetle in disguise of has the person really spent the cash. If I was driving a £100k car I would not want it looking like a kit car!!!  

[trustytrev]

Completely unsurprised - exactly what I'd expect and matches my own experiences as a OO modeller.

 

I discovered years ago that it's imperative to check the facts on the ground and not rely on what you'd always been told was true by someone . It's startling what crawls out when you start lifting stones with your dial calipers in hand

 

Normally Hornby locos are 14.4mm, and when Sandakan were making them they were very consistant. But they went through a brief phase of 14.1mm and 14.2mm on locos around 2000-2.  Bachmann could vary between 14.3mm and 14,5mm on the same loco 

I wonder if the information herehttp://www.ehow.com/how_7587515_calibrate-dial-caliper.htmlandhttp://www.ehow.com/how_4886264_calibrate-digital-caliper.html would affect results that people claim as cast iron with calipers.

trustytrev.

[Ravenser]

Presumably they are labelled for DOGA Fine? The traditional BRMSB back-to-back for 00 has always been 14.5mm.

 

However, the critical dimension is the 15.2mm max back-to-flange dimension, so the optimum back-to-back will depend on the flange thickness.

 

 

 

Markits (Romford) wheels fit matching supplied axles with squared ends for quartering. They are quoted 14.5mm back-to-back for 00, and 16.5mm back-to-back for EM.

 

Martin.

 

 

Martin:

 

Gibson wheels , and the OO gauges sold by C+L were originally supplied at 14.8mm back to back ie EM -1.7mm . (Apparently Keen-Maygib wheels were the same)

 

 At some point during the 1990s Alan Gibson (and it was Alan Gibson in those days) decided unilaterally to change the B2B to 14.7mm . I don't think anyone knows why, as he never announced the fact - he just did it on the quiet. The B2B gauges C+L sold in the 1990s and the first decade of this century were in fact Alan Gibson gauges - they may still be

 

This C+L/Gibson form of finescale OO, using EM profile wheels and flangeways but with the B2B and gauge reduced by 1.7mm is what DOGA formally defined with datasheets in 2001, as the OO Finescale standard. 

 

However it had been around for about 15 years by that point, supported by wheels , gauges and components  from the prominent finescale traders, and promoted as modern finescale OO practice - but without anyone actually putting figures down on a piece of paper as a formally defined standard so that people knew exactly what they were working to (Which is how Alan Gibson was able to change the B2B on the quiet) .

 

 

 

This was quite strongly promoted by Iain Rice in 1993-5  when he was involved with MORILL - documentation can be found (eg) in MORILL 1/1  in the Exam section of his Depot feature  and in MORILL Handbook No.1 Detailing and Improving RTR Wagons ch 1 p4-5, and more substantially in ch 2 p11-12 , with some reference in No.2 Plastic Wagon Kits   (As an aside that first MORILL Handbook was one of the most inspirational modelling books I've ever bought - at least for me at that stage of my interest) 

 

As far as the B2B of Romford locomotive wheels is concerned, what's written on the packet is in a sense irrelevant . If you assemble them to the axle using a 14.5mm B2B gauge, that's the B2B you'll get. If you use a 14.4mm B2B gauge, you'll get that. And if you assemble them using a nice "modern" finescale OO B2B gauge from C+L or Gibson you'll get 14.7mm . How many people have done that unawares because they thought they were using the latest and best products in the form of a proper gauge for finescale OO (whatever that is) is an interesting question.

 

 

As far as I'm aware Gibson , Ultrascale (and their day Keen-Maygib) simply call their products "OO wheels", and always have. They've never explained to anyone exactly what they are. Thus the Ultrascale website says :

 

This range includes the most common locomotive and rolling stock wheels and conversion packs for proprietary, ready to run locomotives. Most of these items can be supplied for either 'OO' Fine scale, E.M. or 18.83 gauges.

 

.............

3'61/2" LMS 10 Spoke tender STANIER.

 

This is our latest new tender wheel for use on the Ivatt Class 4 also know as 'Mucky Ducks or Pigs' it is available in 'OO', EM and 18.83 gauges

 

 

 

They don't even mention that the OO wheels and EM wheels are to the same profile, though clearly they are. And the 9 page pdf data sheet on the wheels never mentions anything about the profile , back to back , flange width and depth etc.

 

With the greatest respect, the fact that you were completely unaware that for the last 25 years Gibson and the old Keen-Maygib wheels have been supplied with a 14.7mm or 14.8mm B2B is exactly what I meant by being ignorant of the conditions on the ground , because you don't work in OO.  Because your own interests lie in other scales and other standards there's no reason for you ever to work with any of these products or have direct experience of these practicalities

[Ravenser]

I wonder if the information herehttp://www.ehow.com/how_7587515_calibrate-dial-caliper.htmlandhttp://www.ehow.com/how_4886264_calibrate-digital-caliper.html would affect results that people claim as cast iron with calipers.

trustytrev.

 

 

I've never blown down the calipers with compressed air but I do check that the dial is reading zero before measuring (and yes I do know where the adjustment screw is on my dial calipers)

 

I accept that every measurement is subject to a degree of tolerance/error/imprecision. But when your dial calipers  have 0.05mm divisions on the dial as mine do, and readings taken with the same instrument in the same session vary by 0.5mm or 0.6mm , then the difference you are measuring is real. The measuring error ought to be pretty consistant

In theory my instrument ought to allow readings to 0.025mm accuracy - I wouldn't really trust any value quoted to more than 1 decimal place of a mill (eg 14.4mm or 14.5mm )

 

Put another way , even if your values are only 99% accurate , that's an awful lot more accurate than making assumptions based on what someone told you years ago