OO vs EM vs P4 comparison photo

[dj_crisp]

I'll do exactly as fulton suggests.

 

From photos I'd definitely have chosen P4. I'd made up my mind I wanted to standardise wheels and OO at the time wasn't great and I hadn't heard of OO SF so it was an easy choice to go EM as P4 was a stretch for me as I wanted to convert lots of RTR.

 

If you're looking at the photos to see that modern OO can look pretty good then they're worth it. However photos don't show how a train runs over the track. I'm always in awe of seeing locos glide over P4. EM is next best and so on.

 

Main choice has to be your enjoyment which photos don't show. I enjoy messing about getting stuff to run well but if I'm being honest much of the modern OO works as well. Going down the EM has helped me apply a disciplined approach which will hopefully reflect across the fleet. Any gauge having consistency is key.

[Reorte]

You may have already done this and are now in the position of trying to find see where things lie with regards to whatever you want, but the question is what do you want? Ease of building? As accurate a reproduction in scale as you can manage? Or somewhere in between? It's easier to make up your mind if you're not aiming for somewhere in between!  Do you have an idea of where you'll find the attention to detail an irritating waste of time, or where the inaccuracies will be a constant, grating annoyance? If you're pretty sure of where those boundaries lie for you (there's no right or wrong answer, it's entirely personal preference) then that'll help.

 

But I will say don't think "I'm not that keen on this or that but I'll put up with it," because you'll probably regret it.

[Jeff Smith]

17 hours ago, Hal Nail said:

I think the answer is to have your baseboards at eye level!

Agreed, but from the front the gauge is very obvious, as is the tyre width.  Gauge is not so obvious from the side but the wheel flanges are, especially on steam locos and diesel shunters.....

[Mark Forrest]

13 hours ago, Qweqwe said:

...any chance you could take another photo of the 3 wagons on the 3 different gauge tracks from directly in front?

I'm away for a few days, but happy to do that at the weekend when I'm back

[Ravenser]

9 hours ago, dj_crisp said:

 

Sound advice. I've always wondered how RTR has got on with code 75 bullhead track. My only experient using RTR wheels set at EM found them to catch all of the chairs on my bullhead track. So I abandoned that approach

 

I've used SMP bullhead flexible in  OO and had no problems. On the other hand I have seen the issue on C+L flexible some years ago.

 

C+L has more prominent chairs than SMP, and the tale doing the rounds at the time (15-20 years ago)  was that there had been slight damage to the mould for the C+L OO trackbase which resulted in one or two of the chairs being slightly raised. I believe this mould has since been replaced 

 

For that reason, I went with SMP.

 

I would imagine that Peco were careful to ensure their 16.5mm bullhead flexible would have no problems with modern wheels . But I haven't build a new OO layout since it was introduced, so I have no direct experience 

[roythebus1]

Abut 14 years ago someone visited me to buy some secondhand stuff. He saw my layout which I'd recently laid to 00 fine scale using hand-built track but using Templot to design the track. He commented how good the P4 track looked. I told him it was 00, he was surprised. A lot of the appearance is the flow of the track using Templot, getting away from the train set curves on pointwork, the fixed radius. Regardless of the actual track gauge, getting the pointwork right is the biggest part of it.

[johndon]

On 20/05/2024 at 20:30, davefrk said:

Any code 75 track can look good once painted and ballasted, my Layout is EM and having dabbled with P4 and decided on the layout I wanted EM was the best option for me. Yes some will notice the checkrails, some will notice the wider gauge but for me it's the running qualities.

 

Boards split for ballasting.

 

Dave.

 

Pretty sure I've said this before Dave but yours is among the best trackwork I've ever seen, regardless of gauge.

[Enterprisingwestern]

20 hours ago, dj_crisp said:

 

Sound advice. I've always wondered how RTR has got on with code 75 bullhead track. My only experient using RTR wheels set at EM found them to catch all of the chairs on my bullhead track. So I abandoned that approach

 

They don't catch on all rtp track, Scaleway f'rinstance from memory.

 

Mike.

[davefrk]

11 hours ago, johndon said:

 

Pretty sure I've said this before Dave but yours is among the best trackwork I've ever seen, regardless of gauge.

Well thanks very much John, track is one of my interests so I had to make an effort or people might talk. 🤣

I was looking at your video on Scalefour forum earlier, nice to see stuff running and running well.

 

Cheers Dave.

[martin_wynne]

On 17/05/2024 at 22:39, ikcdab said:

I think a lot is down to visual appearance.  I model in 16.5mm, but I use finescale track and handbuilt pointwork.  My track is level and true and each section is wired.

I get near perfect running and i think my track looks as good as EM or P4. Without the comparison pic you have asked for, you would not notice the gauge. The big advantage is that I can buy stock and plonk it straight on the track without fiddling with the wheels.  I can visit friends and they can bring their stuff to mine for running. I can sell surplus stock into the OO second hand market easily.

I am very happy with my finescale OO.  For me it has all the advantages of EM without the changing wheels hassle.

@ikcdab

 

The entire argument for 00 summed up in a single post.

 

Martin.

[Enterprisingwestern]

On 17/05/2024 at 23:39, ikcdab said:

 For me

 

9 minutes ago, martin_wynne said:

@ikcdab

 

The entire argument for 00 summed up in a single post.

 

Martin.

 

Hardly.

 

Mike.

[Cwmtwrch]

21 hours ago, Reorte said:

Do you have an idea of where you'll find the attention to detail an irritating waste of time, or where the inaccuracies will be a constant, grating annoyance? If you're pretty sure of where those boundaries lie for you (there's no right or wrong answer, it's entirely personal preference) then that'll help.

I agree. But be aware that the discussion of the gauge is not the end of the matter, and is in some ways completely irrelevant to the level of detail you want to work to. I'm a P4 modeller, because the appearance with or without rolling stock present looks better to me, but most of what I do is some way from  ultimate attention to detail. I rarely use etched brass, and do use a lot of plastic kits [and some r-t-r modified, either by just changing wheels, or building a new chassis]. It all depends what I want to achieve and what is available that I can use to produce a final result consistent with the rest of the stock [so even where I just change wheels, I repaint to get the finish I want]. I prefer a large number of reasonably [to me] accurate wagons rather than a smaller number of wagons with every detail. Iain Rice questioned the need for detail not visible at normal viewing distance, which has always seemed to me to be a sensible approach. 

[DCB]

A lot depends on the size of the space available, and the time available.  I spend a lot of time fitting coarser wheels and less detailed underframes (Hornby Dublo) to 2000 era RTR wagons to improve running on Peco code 100.  With near 100% success.
There is no reason why 00  or H0 cannot equal EM or P4 for running qualities, a recent play with Hornby Dublo 3 rail was eye opening, no derailments or dipping crossing point work as they use flange bearing crossings, like 2020 tech used in the US on full size railroads. At the end of the day with finite  space and copious time P4 and EM make sense, More space and less time RTR makes sense, ruling out P4 ad EM.  My father in Law spent 40 years building his layout, we were going to run to a sequence table when it was finished. He died ad we never had got round to a proper operating session.   Which ever you choose building it on a flat level table will look wrong,  For me getting the ratios right is top prioriy, 4mm "Scale" sleepers with 16.5mm gauge looks ridiculous to my eyes, far worse than H0,maybe its memories of Triang super 4       There's more than one way to skin a Rice Pudding.

[martin_wynne]

47 minutes ago, Cwmtwrch said:

But be aware that the discussion of the gauge is not the end of the matter,

 

It has been a constant mystery to me that modellers are so fixated on the distance between the rails.

 

The model track gauge is a secondary issue. The first and most significant consideration is the wheel profile. For practical reasons it is desirable in many cases that model wheel flanges should be deeper than the prototype. In order for wheel flanges to run smoothly they need to be angled. Which means that deeper flanges are also thicker than the prototype and need wider flangeway gaps than the prototype. Which in turn means such wheels are wider than the prototype to span the gaps. Then to fit such wheels within a scale model, the distance between the wheels on the axle needs to be reduced. So that the distance across the outer wheel faces remains to scale, and fits inside scale splashers, behind scale axleboxes, behind cylinders and valve gear, etc. The upshot of moving the wheels closer on the axle is that the track gauge needs to be reduced accordingly.

 

i.e. start with the wheels and then calculate what track gauge is needed for them to run on.

 

If you start with the track gauge and insist that it is to exact scale you can end up with a situation such as in H0 gauge, where no model can be a scale model because the distance across the outer faces of the wide RTR wheels is overscale, and models have to be wider than scale to accommodate them.

 

If you want to use an exact scale track gauge you need to do the same with the wheel profile. Which means that wheel flanges are tiny, easily rendered ineffective by a build up of dirt on an operational model railway, and requiring an exceptional standard of baseboard carpentry to create the required track levels. It's all doable, but it's not easy.

 

Martin.

 

Edited May 22 by martin_wynne

[Pacific231G]

As someone who doesn't have a horse in this race (I model European H0) These are my hopefully unbiased observations, mainly from exhibtions.

When seen end on, the narrow gauge of 00 is very evident whatever the wheel standards.

On plain track laid to the same standard (not standards),  I can see no visible difference in the gauge between EM and P4, but, on pointwork, the narrower check rail clearances of P4 are evident.

On stock, the finer wheels of P4 do look better (though the finer EM standards adopted by e.g. Pendon look very little different from P4 to my eyes). The same is true between H0 and P87 and I know that many P87 modellers simply use normal H0 track with finer frogs and guard (check) rails dropped in. 

I'm afraid that my own observations from exhibitions are that, though many run very well,  P4 layouts overall do  seem to suffer from more derailments than do EM layouts overall.

 

I think the problem of wheel drop is mainly because 00 (and European H0) wheel standards are not very consistent so the RTR track manufacturers had to build a degree of "slop" into their products to accomodate this. Very early on in my adult modelling I built a small N. American layout with a mixture of Shinohara and home made turnouts. Both were to the then current (1970s) NMRA standards as were the RP25  wheelsets of even relatively inexpensive (shake the box kits) rolling stock and the far smoother running than I'd experienced before or since with RTR products from  this side of the pond was remarkable. 

Edited May 22 by Pacific231G

[Jeff Smith]

36 minutes ago, martin_wynne said:

If you want to use an exact scale track gauge you need to do the same with the wheel profile. Which means that wheel flanges are tiny, easily rendered ineffective by a build up of dirt on an operational model railway, and requiring an exceptional standard of baseboard carpentry to create the required track levels. It's all doable, but it's not easy.

Hence the need for compensation in P4.....this is not rocket science!  However I believe this is the single aspect that puts a lot of modellers off P4 and they therefore settle for EM.  For me EM has all the disadvantages of OO and very little of the advantages of P4......

 

Yes P4 track needs care in laying but compensation overcomes reasonable discrepancies.

[johndon]

9 hours ago, Jeff Smith said:

Hence the need for compensation in P4

 

No need for it at all - none of my wagons (a mix of RTR and kit built) thus far, have compensation and none of them fall off on my track work which, I think, is fairly complicated...  As Martin says, dirt build up is a distinct problem though.

 

Edited May 22 by johndon

[Hibelroad]

One consideration is that no one is wedded to a scale or gauge, many tinker around with a variety of scales. If you give one of the alternatives a try and find it’s not for you then very little is lost and experience will have been gained. 

[martin_wynne]

52 minutes ago, Pacific231G said:

I can see no visible difference in the gauge between EM and P4, but, on pointwork, the narrower check rail clearances of P4 are are evident.

@Pacific231G

 

In order to create an entirely convincing model of real track, the flangeway gap needs to be narrower than the rail head. On the prototype the difference is significant -- rail head 2.3/4" (70mm), flangeway gap 1.3/4" (44mm).

 

In 4mm/ft scale (0.92mm rail head) only 3 track standards meet this requirement:

 

S4-X (the exact-scale variant of P4) : 0.58mm flangeway gap.

 

P4 : 0.67mm flangeway gap.

 

EM-SF : 0.8mm flangeway gap.

 

At present only a few modellers are tinkering with EM-SF. It seems to me to be the ideal compromise between an exact-scale static model, and the practicalities of building a working model railway. Moving from standard EM you have to accept a reduction in the track gauge from 18.2mm to 18.0mm. Many modellers say they can't see such a reduction in track gauge, but can definitely see the difference between 1.0mm flangeway gap and 0.8mm. That's because the change means that instead of being wider than the rail, the gap is now narrower than the rail.

 

EM-SF won't accept RTR wheel profiles, but it runs all EM kit wheels set at the existing back-to-back. Which means EM-SF pointwork can be mixed in with standard EM pointwork on an existing layout. No change to existing or visiting EM rolling stock is needed (but not suitable if it has widened RTR wheels). EM-SF requires minimum radii similar to P4, but sharper curves can be used with appropriate gauge-widening.

 

Until recently trying something such as EM-SF would require making gauge tools and sourcing suitable components. Now with Templot plug track it is just as easy to make EM-SF track as any other. Just one click to change to EM-SF and off you go. No gauge tools are needed. Make all your own components. If plug track is new to you, here is an introductory video from James Waters:

 

 

 

 

Martin.

[Pacific231G]

7 hours ago, martin_wynne said:

@Pacific231G

 

In order to create an entirely convincing model of real track, the flangeway gap needs to be narrower than the rail head. On the prototype the difference is significant -- rail head 2.3/4" (70mm), flangeway gap 1.3/4" (44mm).

 

 

I agree that it's that ratio between rail head and flangeway gap not the gauge that makes the greatest visual difference between "normal" EM (and to some extent, at least when seen from the side, 00) and P4 built to the same overall quality. So the idea of reducing the gauge to achieve the same visual result is interesting and I wonder whether anyone has tried it in 1:87 scale with 16.5 mm track reduced to 16.3mm. Would that work with RP25 profile wheelsets?  

Edited May 22 by Pacific231G
clarity

[roythebus1]

6 hours ago, Pacific231G said:

I agree that it's that ratio not the precise measurement that makes the greatest visual difference between "normal" EM (and to some extent, at least when seen from the side, 00) and P4 built to the same overall quality. So the idea of reducing the gauge to achieve the same visual result is interesting and I wonder whether anyone has tried it in 1:87 scale with 16.5 mm track reduced to 16.3mm. Would that work with RP25 profile wheelsets?  

Well, 00 point kits to 16.2mm gauge are available from Finetrax and run perfectly well with r-t-r out of the box. It's basically EM 18.2mm minus 2mm. As I've said on here before the MRC's "New Annington" 00 exhibition layout branch line was made to 16.2mm gauge by the late Frank Dyer of Borchester fame. I worked perfectly well and that was in the late 1970s, early 1980s and in my view it looked right. I've used 16.2mm pointwork on the Folkestone MRC "Alkham Valley" line when that was converted from EM to 00. There's a couple of places where the difference can be noticed where some of the old SMP track 16.5mm meets up with points at 16.2mm, but it looks right as the pointwork was designed using Templot.

[Enterprisingwestern]

9 hours ago, roythebus1 said:

Well, 00 point kits to 16.2mm gauge are available from Finetrax and run perfectly well with r-t-r out of the box. It's basically EM 18.2mm minus 2mm. As I've said on here before the MRC's "New Annington" 00 exhibition layout branch line was made to 16.2mm gauge by the late Frank Dyer of Borchester fame. I worked perfectly well and that was in the late 1970s, early 1980s and in my view it looked right. I've used 16.2mm pointwork on the Folkestone MRC "Alkham Valley" line when that was converted from EM to 00. There's a couple of places where the difference can be noticed where some of the old SMP track 16.5mm meets up with points at 16.2mm, but it looks right as the pointwork was designed using Templot.

 

You are now closer to 3mm scale than 4mm scale, IMHO, might as well go TT, 16.2mm gauge will exacerbate the narrowness of the trackwork I would have thought?

 

Mike.

[Captain Kernow]

12 hours ago, roythebus1 said:

Well, 00 point kits to 16.2mm gauge are available from Finetrax and run perfectly well with r-t-r out of the box. 

That is NOT true of all RTR manufacturers. Some, yes, but most definitely not all of them. I speak from direct personal experience.

 

 

[martin_wynne]

31 minutes ago, Captain Kernow said:

That is NOT true of all RTR manufacturers. Some, yes, but most definitely not all of them. I speak from direct personal experience.

 

@Wayne Kinney

 

Nor has it ever been claimed that 00-SF (16.2mm) works for all RTR out of the box.

 

This argument has been going on for years and years. Here is a post of mine from 5 years ago summarising the origins and intent of 00-SF (16.2mm):

 

 https://www.rmweb.co.uk/forums/topic/146663-h0-162mm-gauge-crossings/?do=findComment&comment=3772192

 

 

From which: "in recent times it has been found that modern RTR runs very nicely on 00-SF, provided some care is taken to check back-to-backs and correct any rogue wheelsets."

 

As always you don't get something for nothing. But if you are prepared to take some care over checking and adjusting back-to-backs, the advantages are worthwhile:

 

You can mix RTR wheels with kit wheels on the same track without any bumpy running.

 

The narrower flangeway gaps look much better.

 

And since then we have had the introduction of the 00-SF kits from Finetrax which means it is easy for anyone to try 00-SF if they wish.

 

For it to work, the back-to-back of RTR wheels should be not less than 14.3mm. And not more than 14.4mm. Some wider RTR wheels may be ok if they have thin flanges. Most modern RTR complies with this, but you have to be prepared to check and adjust any wheels which don't. For kit wheels the minimum remains the same at 14.3mm, but Romford/Markits wheels can go up to 14.5mm, and Gibson/Ultrascale/EMGS wheels will work better nearer to 14.6mm.

 

Martin.

 

[Captain Kernow]

2 hours ago, martin_wynne said:

@Wayne Kinney

 

Nor has it ever been claimed that 00-SF (16.2mm) works for all RTR out of the box.

 

This argument has been going on for years and years. Here is a post of mine from 5 years ago summarising the origins and intent of 00-SF (16.2mm):

 

 https://www.rmweb.co.uk/forums/topic/146663-h0-162mm-gauge-crossings/?do=findComment&comment=3772192

 

 

From which: "in recent times it has been found that modern RTR runs very nicely on 00-SF, provided some care is taken to check back-to-backs and correct any rogue wheelsets."

 

As always you don't get something for nothing. But if you are prepared to take some care over checking and adjusting back-to-backs, the advantages are worthwhile:

 

You can mix RTR wheels with kit wheels on the same track without any bumpy running.

 

The narrower flangeway gaps look much better.

 

And since then we have had the introduction of the 00-SF kits from Finetrax which means it is easy for anyone to try 00-SF if they wish.

 

For it to work, the back-to-back of RTR wheels should be not less than 14.3mm. And not more than 14.4mm. Some wider RTR wheels may be ok if they have thin flanges. Most modern RTR complies with this, but you have to be prepared to check and adjust any wheels which don't. For kit wheels the minimum remains the same at 14.3mm, but Romford/Markits wheels can go up to 14.5mm, and Gibson/Ultrascale/EMGS wheels will work better nearer to 14.6mm.

 

Martin.

 

This is all very well, Martin, but the two examples of RTR that I have had problems with are both recent productions, by two of the recent entrants into the RTR manufacturing side of things.

 

B2B on both were 14.5mm, but both locos (remember, from different manufacturers) had the same flange profile, featuring a wider-than-average flange. The problems did not start when the locos encountered the flangeway gaps on my pointwork, but on the short section of plain line set at 16.2mm immediately before it. One of these locos is the Accurascale Manor. The loco stalled on the 16.2mm track, unless you increased speed, which then caused the tender to actually derail each time.

 

The other loco was from a smaller manufacturer, which I decline to name, although interestingly they told me that their loco was made in the same factory as the Accurascale Manor.

 

Most of my locos use Markits (or Romford) wheels, but none of my other RTR locos with their original chassis have problems with the 16.2mm gauge, although some find difficulty with the inside chairs of the older C&L flexi track that I have used (such locos then either get a wheel change or a new chassis or are sold on).

 

Due to the Manor also not being a very smooth runner, I sent it back to the retailer and did not get another. The other loco is something that I want to keep, however, but I am now faced with the task of changing the RTR wheels for modern Markits ones, although this is something which I hope will be fairly straightforward.

 

I'm happy to give anything a chance, but I've not had a good experience with OO-SF, so I won't be building any other track to that standard. If anyone asks me about it now, I advise them to steer well clear. The narrowing of an already too narrow gauge seems counter-intuitive to me anyway.

 

I also model in P4, by the way and generally find the experience of building track in that gauge a lot less hassle, due the set of laid-down standards that apply.

 

 

 

 

Edited May 23 by Captain Kernow
Typo.