16.2mm gauge - who uses this and why?

[Ron Solly]

Hi Ravenser,

 

That's true. But for any given track there is an "envelope" of wheel standards which will run acceptably well. ..........................regards,

 

Martin.

 

 

All of the above posts have been very interesting but Martin's comment , extracted from his last post is very telling. To my knowledge, no-where readily available .is a chart indicating what wheels work with with what brand of track either commercial or hand laid.

 

I do feel sorry for someone getting into the hobby buying say Bachmann rolling stock & Commercial code 100 track & points then getting some kits with finer wheels & wonders why they drop !

[James]

All this discussion makes P4 seem very straight forward - one set of p-way standards and another standard for wheels...

 

 

 

 

 

[martin_wynne]

All this discussion makes P4 seem very straight forward - one set of p-way standards and another standard for wheels...

Hi James,

 

Well actually there are two standards.

 

Regular P4 uses overscale flangeway gaps (0.67mm). Ray Hammond's S4 variant uses exact-scale flangeway gaps (0.58mm) and a sightly wider back-to-back. There are quite a few modellers using S4.

 

regards,

 

Martin.

[James]

Hi James,

 

Well actually there are two standards.

 

THere's always confusion when less clued up magazine staff use the term 'S4' to describe P4 layouts!

 

But strictly speaking there is one P4 standard! And it has stood the test of time - some of the track gauges used on Botanic Gardens are ancient Studiolith ones and they work perfectly alongside modern version

 

It looks like 00-SF has promise but I'm not aware I've ever seen a layout in this standard. I wonder if it would also have promise when used with 7 mil' narrow gauge too. I think Gordon Gravett may have tried something similar with the Tal-Y-Lyn diorama he built which featured in the third MRJ Compendum.

[dave_long]

Hi James

 

There are a few SF layouts about, check my Pensnett link below, not the greatest layout but the trackwork is all SF handbuilt with mostly exactoscale chairs on peco sleepers.

 

 

[martin_wynne]

There are a few SF layouts about, check my Pensnett link below, not the greatest layout but the trackwork is all SF handbuilt with mostly exactoscale chairs on peco sleepers.

Hi Dave,

 

It looks a fine layout to me -- how about an update?

 

There aren't many layouts using the DOGA Fine 00 standards either. I've just been looking through RMweb without finding any. I believe Gordon S started his amazing Eastwood Town project in DOGA Fine but later changed to DOGA Intermediate (00-BF).

 

regards,

 

Martin.

[RedgateModels]

Hi James

 

There are a few SF layouts about, check my Pensnett link below, not the greatest layout but the trackwork is all SF handbuilt with mostly exactoscale chairs on peco sleepers.

 

 

 

 

And very nice it looked too last time I saw it

 

 

 

 

 

[dave_long]

Thanks for the comments guys, but unfortunately mother nature took a dislike to the baseboards. She's had to go to the great exhibition in the sky. However although I've moved mainly to P4 there is a small sf layout on the horizon (think Shell Island but based in rural Staffordshire).

 

I knew there was another impressive sf layout on this forum, but I found the link on the old forum, the OP has posted on the yahoo group a stunning looking SR layout Coin street . Also I think that Hayfield started building sf points on his layout but he was mixing with rtr I think.

 

 

[Ravenser]

Hi Dave,

 

It looks a fine layout to me -- how about an update?

 

There aren't many layouts using the DOGA Fine 00 standards either. I've just been looking through RMweb without finding any. I believe Gordon S started his amazing Eastwood Town project in DOGA Fine but later changed to DOGA Intermediate (00-BF).

 

regards,

 

Martin.

 

 

Bath Green Park would be one. (Bear in mind the DOGA OO Finescale standard is a codification of an ideal widely touted in the early/mid 90s before DOGA was formed)

 

So would any layout built using the OO gauges sold by C+L - which I suspect means most of those buying C+L OO components for track building

 

However one thing that does seem to emerge when you do some digging is that there are 3-4 people working in OO using the old BRMSB track standard for every one using the tighter flangeway and Gibson/Ultrascale wheels throughout and working to OO Finescale , strictly defined

 

You do have to ask some careful questions , though, to establish exactly what is going on. "What track gauges do you use to build your track ? Where did you get them" is the key question

 

The lack of readily available standards sheets to serve as a reference point for discussion prior to DOGA publishing its standards led to a situation where nobody knew what "finescale OO" actually meant and the term was used to mean different things by different people . Even worse, different people called the same thing "Universal" and "OO Finescale". [As an example , most people would probably describe Stoke Summit, Charwelton , or the Shipley club's OO layouts Tebay and Leicester S Goods as "OO Finescale" . All to the best of my knowledge are to BRMSB track standards . But Branchlines describes chassis packs as "Universal" if they contain Romfords (ie OO Intermediate, or very close) and "Finescale" if they have Gibsons. Shipley club certainly used to have a OO layout using Peco track, and presumably they would have regarded "Universal" as describing that - not Tebay and Leicester S Goods.....]

 

There is certainly a significant minority of people working to the DOGA OO Finescale standard - even if they may not use that as the label for what they do, and even if they are a minority of those using handbuilt OO track.

 

I suspect the question "who on RMWeb has built their OO points using C+L gauges" would flush out quite a few

 

But the fact that a large majority of handbuilt OO track is (still) to BRMSB belies the comments widely and loudly made in the 1990s about the "obsolete/defunct BRMSB standards" which it was implied had been consigned to history by the advance of the finescale movement. I believe that this was a case of people asserting strongly what they would have liked to believe was true and felt ought to be true - without really checking the facts on the ground, which told a different story.

 

I have an awkward feeling Pensnett may be the only completed OO-SF layout around

[gordon s]

Seems I'm in for another bumpy ride. Just taken delivery of a beautiful set of Ultrascales for my Heljan Teddy Bear. Blown away with the quality of the product but 2.33mm wheel thickness and 14.77mm B2B.

 

Decisions, decisions....Rewheel all my stock to 14.8mm and 1mm flangeway or go down the 00-SF route when I can get some gauges or just put up with the bumps...

 

Never had this problem with Hornby 3 rail...

[Ravenser]

Yep, Ultrascales are (or should be) EM 1979 Profile - right in the same bracket as Gibsons.

 

I really can't see much point rewheeling RTR for OO with Ultrascales these days - the wheels they come with are a better fit to most OO track

 

(Heljan do a pretty good version of RP25/110 profile wheels. Pity they set them to 14.2mm B2B)

 

For the record, Ultrascales should use the OO Finescale B2B of 14.8mm when running on 16.5mm gauge track

 

Max Stafford

It's an interesting thread and to be honest I'd no idea there was this much to humble 00! I was under the impression that modern models had their wheels made to RP25 profile, but it seems I was hugely mistaken. At least my kit-built locos have RP25 wheels though as I use the new finer scale Markits sets on my new-builds. My track, such as it is consists of SMP and now Shinohara items. I'm hoping this will help keep things simple, but having taken little to do with track standards apart from developing a strong preference for code 75, I'm still on the learning curve.

 

All current RTR (with the possible exception of Vi-Trains)is an interpretation of RP25/110 - some manufacturers' interpretations being a bit freer than others, but essentally at a first order approximation, its the same thing .

 

I'm afraid the "RP25-ness" of your kit built locos is in more doubt thatn the RTR. Markits claim this is "RP25-100" , and I've never seen such a profile listed by the NMRA on any data sheet. RP25-110 , yes (standard for HO RTR) , and RP25-87 yes (a "fine" version approximately equivalent to EM1979, and found on Tenshodos and many Black Beetles)

 

But "RP25-100" : no

 

The story I heard second hand was that Markits cited , not an NMRA datasheet, but a copy of the Model Railroader from the early 1960s as the authority for their wheel profile.

 

I must say that doesn't sound very convincing to me. I don't think they are using a wheel profile currently recognised by NMRA as a standard - nor one recognised in the recent past.

 

Whether the NMRA really had such a standard half a century ago, I don't know : perhaps some of our US members may recognise this . But at best , "RP25-100" is long obsolete , and the whole thing sounds rather dubious to me

 

At a practical level you'd be best placed using traditional 1.25mm flangeway gauges, which I believe SMP supply, and simply checking the B2B rigourously

[martin_wynne]

Whether the NMRA really had such a standard half a century ago, I don't know : perhaps some of our US members may recognise this . But at best , "RP25-100" is long obsolete , and the whole thing sounds rather dubious to me.

Hi Ravenser,

 

The RP25 profile can be applied to any wheel width -- NMRA have a spreadsheet available for the purpose. I see nothing wrong in Romford/Markits describing their wheels as RP25/100 if they have generated the profile accordingly.

 

However, the nearest standard NMRA wheel width is RP25/93: http://www.nmra.org/standards/sandrp/pdf/RP-25%202009.07.pdf

 

regards,

 

Martin.

[nswgr1855]

The Australian Model Railway Association (AMRA) has placed on its website it's new standards. http://www.amra.asn.au/standards.htm It has 2 standards relevent to 00. The AMRA H0 fine tolerance wheel and track standard is equalavent to 00-SF and has all the advantages of 00-SF. The AMRA H0 intermdiate tolerance standard is compatable with older coarser wheels. Other standards of interest to UK modellers are the AMRA minimum radius standard and track centre standard.

 

Terry Flynn.

 

Hi Ravenser,

 

That's true. But for any given track there is an "envelope" of wheel standards which will run acceptably well. The great advantage of 00-SF is that the "envelope" is just about wide enough to include most RTR wheels (as supplied) at one extreme, and the EM wheel profile at the other extreme. Plus traditional "Scale 00" wheels (Romford/Markits) in the middle.

 

Which means that by adopting 00-SF you can run all 3 wheel standards together and without bumping on the crossings. None of the other 00 track standards offer this.

 

It's not perfect. If you were running only RTR wheels, 00-BF (DOGA Intermediate) is more tolerant of poor manufacturing quality control, and standards variations.

 

If you were running only EM profile wheels, there's an argument for going a bit tighter, say 0.9mm flangeways on 16.1mm gauge. This would give a bit more scope to correctly model the blunt nose on crossing vees.

 

But as it stands 00-SF splits the difference and makes the best of a bad job.

 

regards,

 

Martin.

[martin_wynne]

The Australian Model Railway Association (AMRA) has placed on its website its new standards. http://www.amra.asn.au/standards.htm It has 2 standards relevant to 00. The AMRA H0 fine tolerance wheel and track standard is equivalent to 00-SF and has all the advantages of 00-SF. The AMRA H0 intermediate tolerance standard is compatible with older coarser wheels.

Hi Terry,

 

Thanks for that.

 

However, there seems to be something amiss with the quoted wheel widths.

 

The basic rule for all railways is that the wheel width should be at least equal to double the maximum flangeway gap. And then some more to allow for a prototypical blunt nose on the vee, the top corner radius on the wing rail, and a small chamfer between the face of the wheel and the tread.

 

Otherwise the wheel will not be fully supported on the level as it runs over crossings (frogs) and is liable to drop in the gap with a bump.

 

I suggest the minimum wheel width for 00-SF and EM should be 2.3mm, in line with the EMGS standard and the NMRA code 88 standard.

 

I suggest the minimum wheel width for 00-BF (DOGA Intermediate) should be 2.8mm, in line with the NMRA code 110 standard.

 

regards,

 

Martin.

[nswgr1855]

Martin,

 

The AMRA standards are designed to be as broad as possible, allowing the least compromise in wheel width in 1/87 scale. You are correct to note at the minimum limit of wheel width and the maximum limit of flangeway there will be some wheel drop. Testing indicates the wheel drop for the values in the standard is minimal and only detected by feel only. I have done a quick grapical solution in a cad package, and caculated the theoretical wheel drop of a 9mm diameter wheel with a 0.2mm blunt #8 crossing V. The resultant wheel drop is only 0.04mm. A 0.5mm blunt crossing results in a wheel drop of only 0.23mm. My conclusion is the double wheel width rule of thum used in the AMRA standard is OK and ther is no need to go to a larger minimum width. However this does not stop people working in 00 from using a wider wheel, which may be closer to prototype dimensions. If your trackwork is within the recommended values of the standard I see no problem. The use of finescale wheels on the intermediate tolerance standard can result in noticeable wheel drop, and how much, as seen above depends allot on the sharpness of the crossing V. For a 2mm blunt V crossing using 1.3mm flangeways the wheel drop is going to be around 0.42mm, not enough to derail the wheel in theory. You can get away with it 99.9% of the time.

 

Cheers,

 

Terry Flynn

 

 

http://angelfire.com/clone/rail/index.html

 

HO wagon weight and locomotive tractive effort estimates

 

DC control circuit diagrams

 

HO scale track and wheel standards

 

Any scale track standard and wheel spread sheet

 

 

 

 

Hi Terry,

 

Thanks for that.

 

However, there seems to be something amiss with the quoted wheel widths.

 

The basic rule for all railways is that the wheel width should be at least equal to double the maximum flangeway gap. And then some more to allow for a prototypical blunt nose on the vee, the top corner radius on the wing rail, and a small chamfer between the face of the wheel and the tread.

 

Otherwise the wheel will not be fully supported on the level as it runs over crossings (frogs) and is liable to drop in the gap with a bump.

 

I suggest the minimum wheel width for 00-SF and EM should be 2.3mm, in line with the EMGS standard and the NMRA code 88 standard.

 

I suggest the minimum wheel width for 00-BF (DOGA Intermediate) should be 2.8mm, in line with the NMRA code 110 standard.

 

regards,

 

Martin.

[Taz]

Just a thought, but could you not use DOGA Fine gauges to set the crossing at the vee at 1mm and then increase the spacing of the check rails on the outer rails to compensate and still use rtr with 14.5mm b2b and 16.5mm gauge?

I would guess the outer check rails would need to have around a 1.4mm flange gap. This would then give you the fine appearance at the vee (which is where I think the most visual benifit is gained) without the additional hassle of having to make major adjustments with your rtr b2b.

 

Is this a practical approach?

[martin_wynne]

Just a thought, but could you not use DOGA Fine gauges to set the crossing at the vee at 1mm and then increase the spacing of the check rails on the outer rails to compensate and still use rtr with 14.5mm b2b and 16.5mm gauge?

Hi Brian,

 

The check gauge is the fundamental dimension of a standard, so if you change it you are no longer using the same standard.

 

What you are describing is not DOGA Fine -- it's actually 00-SF with full gauge-widening applied. Such widening is necessary for sharply curved turnouts and is applied by means of the 3-prong 00-SF track gauge tool. The result is a flangeway gap of 1.3mm at the check rail, while retaining the 1.0mm flangeway gap at the crossing (frog).

 

However, such asymmetric flangeways are a problem in more complex formations, where often a wing rail on one crossing is extended to form the check rail on another crossing. For such formations it is better to avoid sharp curving and stick to the 00-SF 16.2mm track gauge throughout, with 1.0mm flangeways on both sides.

 

 

This would then give you the fine appearance at the vee (which is where I think the most visual benifit is gained) without the additional hassle of having to make major adjustments with your rtr b2b.

Which neatly sums up the advantage of 00-SF over DOGA Fine -- same improved appearance and running, but no need to change wheels back-to-back. This means:

 

1. your stock remains fully interchangeable with other 00 layouts.

 

2. other 00 stock can run on your layout.

 

3. newly purchased RTR stock does not have its guarantee voided or resale value affected.

 

4. you can mix 00-SF with 00-BF (DOGA Intermediate) and even Peco pointwork on the same layout.

 

regards,

 

Martin.

[Nickey Line]

If my three penny worth is of any use, I recently completed an Inglenook to 00 Fine. The main reason I chose this format was the cost of track gauges for 00SF, but this as it turns out was probably a false economy. Having to adjust all the B-to-Bs, particularly on locos, is a real faff. Keeping the quatering and squareness on the axles correct is tricky to say the least. With hindsight I should have chosen 00SF, and indeed will probably convert to this standard for any future (larger) projects (if I don't go P4 that is...).

[rjh]

Hello,

 

This is to update anyone hat has recently tried to contact

stores@00-sf.org.uk regarding supply of 00-SF gauges.

 

The 'stores' is run by Brian Tulley, who has been

incommunicado for a while due to the severe illness,

and now demise, of a very close relative of his.

 

It will be several weeks before Brian is able to attend

to 00-SF stores matters and he asks that folks are patient.

 

The good news is that the new gauges are ready for despatch

from the machine shop. These replace those that formerly came

from our our late American supplier, Russ Simpson.

 

Please check the 00-SF Yahoo Group postings from time to time

for further news.

 

Thank you.

 

 

Regards,

Rodney Hills

00-SF Group owner.