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Drakelow


ianb3174
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Just now, Gordon A said:

So what happened to the P4 Drakelow?

 

I became sidetracked by other projects, most of which came to nothing. The board was left in my shed and was subsequently water damaged. Only recently have I decluttered to give myself some new railway space. Hence another start. I still have a lot of the P4 track parts hence the EM-SF possibilities. The root idea is still the same but the plan has been mirrored and lengthened 

 

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1 hour ago, Andy Reichert said:

If the flange way of an existing known 100% viable track standard is reduced, the minimum radius restriction is increased. I'm not sure where the concept (and measurement of ) running improvement beyond 100% OK comes from.

 

Sigh. Andy, why is it every time I post anything about track standards, you immediately throw cold water on it? I'm sorry EM-SF hasn't been certified by your NMRA, but several folks like it nevertheless.

 

Better running? Here you go:

 

Standard EM: for full support through bullhead crossings, minimum wheel width is total of:

2 x 1.0mm flangeways, 

1 x 0.25mm blunt nose on vee (3/4" for bullhead - 0.25mm) 

1 x 0.1mm arbitrary allowance for top corner radius on rail (1/2" rad = 0.17mm rad)

1 x 0.05mm chamfer between wheel tread and front face of wheel

________

2.40mm total = minimum wheel width for full level support under all circumstances on standard EM.

 

However, EMGS profile wheels are narrower than this at around 2.3mm, and likewise NMRA Code88 wheels at around 2.25mm. Consequently they can suffer a slight dip when running through standard EM crossings. Not much, and not always, but the possibility exists.

 

edit: The same applies to 00-SF when using those wheels.

__________________________________________________________________________________

 

EM-SF: for full support through bullhead crossings, minimum wheel width is total of:

2 x 0.8mm flangeways, 

1 x 0.25mm blunt nose on vee (3/4" for bullhead - 0.25mm) 

1 x 0.1mm arbitrary allowance for top corner radius on rail (1/2" rad = 0.17mm rad)

1 x 0.05mm chamfer between wheel tread and front face of wheel

________

2.00mm total = minimum wheel width for full level support under all circumstances on EM-SF.

 

All EM wheels are wider than this. Consequently running will be fully supported and rock-steady under all circumstances on EM-SF.

 

cheers,

 

Martin.

Edited by martin_wynne
00-SF note added
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59 minutes ago, ianb3174 said:

I became sidetracked by other projects, most of which came to nothing. The board was left in my shed and was subsequently water damaged. Only recently have I decluttered to give myself some new railway space. Hence another start. I still have a lot of the P4 track parts hence the EM-SF possibilities. The root idea is still the same but the plan has been mirrored and lengthened 

 

Shame.

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1 hour ago, Andy Reichert said:

If the flange way of an existing known 100% viable track standard is reduced, the minimum radius restriction is increased.

 

Andy

 

Hi Andy,

 

That is usually the case. There was an article in, I think, Model Railway Journal, a good while back where the chap was suggesting that EM-SF held some benefits in running qualities. I couldn't understand if it was going to be worth it but at some point I made some trial pointwork, modified some back to backs on the wheels and gave it a go. It ran well and later when I tried different stock on it I was impressed that the pointwork was performing well. You don't get the choice of simply using RTR wheels ( Hornby, Bachmann etc ) as the flanges are too thick, so it needs to be Gibson, Ultrascale or a trip to the lathe. Wheels that run on EM-SF are happy to run on other people layouts building to standard EM so you are not isolating yourself too much.

 

It was only later when I noticed it was much better visually. This is because the flangeway gaps are now less than the rail head width, which is what we are used to seeing on 1:1 scale railways. This now only applies on bullhead turnouts as there now isn't a 0.9mm head width flat bottom rail available ( since the demise of Peco IL-115).

 

Surely 'viable' in your quote can apply to the visual aspects of track and not just to the running qualities ?

 

Rob

 

 

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Hi Rob,

 

The all-important check gauge is the same for standard EM and EM-SF at 17.2mm (min). So there shouldn't need to be any difference in back-to-backs, and kit wheels should be interchangeable on standard EM and EM-SF. If you have tweaked the back-to-backs for optimum running on EM-SF, they will also be better on standard EM.

 

Sorry Ian that your layout topic has been hijacked by Andy R and this track standards stuff. sad.gif

 

cheers,

 

Martin.

Edited by martin_wynne
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39 minutes ago, robmanchester said:

 

Hi Andy,

 

That is usually the case. There was an article in, I think, Model Railway Journal, a good while back where the chap was suggesting that EM-SF held some benefits in running qualities. I couldn't understand if it was going to be worth it but at some point I made some trial pointwork, modified some back to backs on the wheels and gave it a go. It ran well and later when I tried different stock on it I was impressed that the pointwork was performing well. You don't get the choice of simply using RTR wheels ( Hornby, Bachmann etc ) as the flanges are too thick, so it needs to be Gibson, Ultrascale or a trip to the lathe. Wheels that run on EM-SF are happy to run on other people layouts building to standard EM so you are not isolating yourself too much.

 

It was only later when I noticed it was much better visually. This is because the flangeway gaps are now less than the rail head width, which is what we are used to seeing on 1:1 scale railways. This now only applies on bullhead turnouts as there now isn't a 0.9mm head width flat bottom rail available ( since the demise of Peco IL-115).

 

Surely 'viable' in your quote can apply to the visual aspects of track and not just to the running qualities ?

 

Rob

 

 

 

I just get very concerned when "better running" claims are made for changing established and long proven 100% operating real Standards to values that are presumably have greater than 100%  non-incidents :o.  Those very frequent claims are there to be read by all visitors to RM Web. Not just the possibly more knowledgeable OP who can make his/her own assessment. Especially when the downsides are not mentioned. For example S4 has finer flange ways than P4. But don't expect a very very slightly wobbly wheel that just runs to spec and OK on P4 to run as well on S4 track. But how would you know the cause of the later apparently random bad running if you were a less experienced modeller?

 

Andy

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1 hour ago, Andy Reichert said:

I just get very concerned when "better running" claims are made for changing established and long proven 100% operating real Standards

 

For heaven's sake Andy. No-one is suggesting changing anything. Standard EM is still Standard EM and any beginner will find it and get perfectly good results with it, as have thousands of others over the years. EM-SF is simply a choice for modelmakers who want to give it a try. The most important point is that it should have its own name, which it does have. Likewise 00-SF.

 

Martin.

Edited by martin_wynne
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I don't mind my thread being used for discussion at all. That's what a forum is for. That's my 0.2mm worth of opinion. 

Dare I mention that I found a bag of 0.68mm check chairs too? Is there a none P4 use for these hidden in Templot Martin? 

IMG_4179 2.jpg

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On 24/01/2020 at 16:08, martin_wynne said:

 

For heaven's sake Andy. No-one is suggesting changing anything. Standard EM is still Standard EM and any beginner will find it and get perfectly good results with it, as have thousands of others over the years. EM-SF is simply a choice for modelmakers who want to give it a try. The most important point is that it should have its own name, which it does have. Likewise 00-SF.

 

Martin.

 

Thanks for providing your "better running reasoning" . I'll be responding fully soon to that when I have sufficient time. There's a lot to reply to factually.

 

Regarding creating new associated names for modified existing standards. For EM it's up to the EMGS to specify other uses for "EM".  For UK 00, the DOGS, and or BRMSB if it still exists. Likewise the NMRA for US HO, and the successor to NEM for continental HO. What you come up with independently in Templot should have a TEMPLOT Prefix to clearly show it's not produced (and approved) under another society's  banner.

 

Andy

 

 

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Background information regarding:  Better Running using -SF gauge narrowing claims.

 

Reference document #1

 

Independent source: http://www.catskillarchive.com/rrextra/tkwk10.Html


1678. The Frog Point.—The theoretical point of frog a' (see Fig. 523) and the actual point a are quite dissimilar. The reason for making a the point of frog is that if the theoretical and actual point of frog were the same, the point would be so small that the first blow inflicted by a passing locomotive or car would completely destroy it. The frog point is accordingly placed at a, where its width is about ¼ of an inch.

 

Reference document #2

 

Source ARA Engineering reference drawings.

 

1764782272_veehalfin.point.jpg.8ae73940905a9bd029a94782b36bf399.jpg

 

Reasoning and Conclusions

 

Note that any blunting of a crossing (frog) vee point is to avoid damage on the prototype from the crushing weight of prototype locomotives on a very narrow steel point tip. The prototype fix as in the diagram above is to cut the height of the point back until the blunt pointed point is strong enough to take the enormous pressure without breaking.  Clearly, this not at all a problem that needs fixing on smaller scale model rail vees, even if finely pointed, as model rail is easily capable of continuously supporting and standing up to the relatively light weight of even the heaviest model locomotives. As of course it also does twice per turnout on even far more finely filed, moving model point blades. The fact that vee blunting has NO useful or functional purpose for small scale model railways is the first reason vee blunting is excluded from the common model railway scale standards, such as HO, EM, 00,

 

If the point of blunting model crossing vees is cosmetic, then it might be considered appropriate for Proto-Scale modelling, where normally invisible very small details can sometimes show up in close up photographs. But for the common scales such as HO, EM, 00, (and as per the diagram above), we are talking about a shallow sliver triangular dulled mark  0.17 mm at it's widest, by about 1 mm long, to it's point. Compared to the around 1 full mm visible excess width of common model railway standard's, non-scale width, model wheels, it is cosmetically insignificant.  However should such a tiny scale amount of vee blunting actually exist on a model turnout, common model standards increase the minimum wheel width by 10% ( 0.25 mm for 4mm scale) to cover any possible lack of wing rail wheel support for that small distance.  But if modellers were told to deliberately file vees blunt, and they were even a little heavy handed, (see Martin's stated 0.025 mm), then the wing rail support distance could be exceeded, which is the second reason why all the common small scales exclude vee blunting from their standards.

 

Why does all this technical detail matter when giving reasons for using  -SF gauge narrowing?  If the reasoning is that -SF  runs better than the common standards, then  the answer, given by all the numbers quoted is that -SF isn't better running compared to the unmodified common standards, However if the -SF numbers quoted are compared with common standards DAMAGED by non-required, deliberate vee blunting, then the  -SF standards may run as well as the undamaged common standards and only possibly better if compared to the common standards if the common standards are reduced to less than 100%, due to damage by using excessive vee blunting.

 

Any cosmetic preferences aside, then the same 100% good running will come from either merely NOT using vee blunting, on common standard's turnouts, or instead, for  -SF  standard variations, by hand laying individual turnouts as specifically custom specifically gauged narrowed.  There is NO basis  for-SF modifications improving running  over existing common standards.

 

Andy

 

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Hi Andy,

 

I hope you feel better for getting all that off your chest. smile.gif

 

The primary reason for using blunt-nose vees in models of UK bullhead track is because folks want to build a model of UK bullhead track.

 

Posting an AREMA drawing show USA practice on flat-bottom track is of no relevance to that at all.

 

In the UK the blunting of REA bullhead vees at 3/4" wide is much greater than in the USA, and is very noticeable to anyone familiar with track. Nothing looks worse than a model sharp-nose vee, especially if it is hanging in fresh air between the timbers, which it must do if the crossing timbering is not also modified from the prototype.

 

Most UK track-building templates show a blunt vee, correctly positioned at the prototype dimension (4" for REA bullhead crossings) from the centre of the supporting "A" timber:

 

blunt_nose1.png.6a34cd040f2b398914ec0f9e270ace0a.png

 

blunt_nose2.png.4000d88f0e35f2560b73a68948290243.png

 

You can see that if a sharp-nose vee is substituted, extending it to the red gauge-intersection mark, it would be unsupported on the timber. Which then requires a further change from prototype dimensions to move the timber centres.

 

However, some users do prefer to use sharp vees, and they are specifically referenced in the 00-SF dimensions relating to crossing flangeway and wheel widths, see:  http://4-sf.uk/dimensions.htm

 

Quote

But if modellers were told to deliberately file vees blunt

 

In the UK modellers are not told to do anything. They are given what is usually helpful information, and are then free to make their own decisions about how they want to build their models.

 

 

Quote

As of course it also does twice per turnout on even far more finely filed, moving model point blades.

 

No it doesn't. If straightcut pattern blades are modelled, they have a finite width at the tip (3/8") which is housed in a joggled stock rail, which assists in supporting the wheel load. If knife-edge undercut pattern blades are modelled, the end section is taken down below the level of the stock rail, so that it it serves initially only to deflect the wheel flange and not to support the wheel. More about this in detail at:

 

 http://templot.com/companion/real_track.php#planing_types

 

Contrary to what you constantly assert from afar, we do actually know what we are doing here in the UK. If you want to take this further I suggest starting a separate topic, either here on RMweb or on the Templot Club forum. Ian's patience must be getting close to being exhausted, in this topic about his layout. If he decides to adopt the EM-SF standard for it, there will be many here watching with interest.

 

cheers,

 

Martin.

Edited by martin_wynne
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5 hours ago, martin_wynne said:

SNIP

The primary reason for using blunt-nose vees in models of UK bullhead track is because folks want to build a model of UK bullhead track.

 

A 4mm scale model of UK Bullhead track has a gauge of 18.83 mm and around 0.6 mm flange ways, not 16 ,2 mm gauge and 1 mm flange ways. Modelling the blunt vee on the latter would seem to be putting lipstick on the proverbial pig.

 

     SNIP

5 hours ago, martin_wynne said:

 

 If you want to take this further I suggest starting a separate topic, either here on RMweb or on the Templot Club forum. Ian's patience must be getting close to being exhausted, in this topic about his layout. If he decides to adopt the EM-SF standard for it, there will be many here watching with interest.

 

cheers,

 

Martin.

 

Been there, done that. See Topic "Fixing "00" Turnouts for "modern" "00" drifting Standards " in "Permanent Way " section dated 12/19.

 

While you  introduced your -SF variations there, you didn't make the Better Running claim there, nor further react to the note that the -SF variation for HO is redundant.

 

My Engineering background, Prototype Railway interaction and Modelling Memberships are all originally from the UK, so I am aware of most of the UK railway technology.

 

Andy

 

 

 

 

Edited by Andy Reichert
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5 hours ago, Andy Reichert said:

A 4mm scale model of UK Bullhead track has a gauge of 18.83 mm and around 0.6 mm flange ways, not 16.2 mm gauge and 1 mm flange ways. Modelling the blunt vee on the latter would seem to be putting lipstick on the proverbial pig.

 

The REA/SRC components can be used to build prototype track to any gauge. For example in Northern Ireland (part of the UK) the track gauge is 5ft-3in (21.0mm).

 

 

you  introduced your -SF variations

 

For the umpteenth time of telling you, the SF gauges are not mine. 00-SF was devised by Roy Miller (of the EMGS) nearly 50 years ago in the early 1970s. 18.0mm gauge was the original EM gauge in the 1950s. 0-SF (31.2mm gauge) and 0-MF (31.5mm gauge) were devised by Jim Snowdon in the 1990s (and since adopted by the Technical Committee of the Gauge 0 Guild).

 

All of these gauges, and others, have been used by various modellers at different times. Who have been entirely happy with them. I include them in Templot for that reason.

 

cheers,

 

Martin.

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  • 2 weeks later...

So, while I pause to reset my verniers to account for this naughty 0.2mm I have used the time to make a start on the fiddle yard. No one can gauge preach yet as I've only laid one rail. 

Construction is fairly standard, 5mm ply and 40mm deep frame, braced at 200mm intervals. The whole assembly is 1200x200mm and will suffice for the size of layout.

Yes I'm using ply sleepers and chairs for it all, but it's a practice for the scenic section. 

I was originally thinking of turnout control via wire in tube and manual levers but then the idea of surface mounted servos accidentally landed in my browser. Plenty to think about as I cut the 0.8mm check rail chairs off the sprue and lose them immediately on the floor. If only there were some kind of magnifying apparatus one could attach to the face for these situations

IMG_4868.jpg

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Spent an hour threading tiny chairs onto tiny rail convinced that Drakelow had transitioned to 2mm Finescale overnight without informing me. A quick check of the verniers reminded me of my earlier choice. Purchase of the year goes to a cheap anglepoise type LED USB lamp which magnifies things to O gauge. Did I mention that after 45 years of railway modelling/planning/thinking I still consider myself a beginner. 

IMG_4931.jpg.5e87da06dc8ca600fac53c0138cedada.jpg

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  • 3 weeks later...

The first turnout well under way using Mk1 eyeball and an 0.8mm feeler gauge. The RH checkrail is in proper checkrail chairs and it all looks nice and consistent. 

The eagle eyed amongst you will note that it isn't even a 'proper' template, just two overlapped bits of plain track, one with the sleepers removed. Hence I have no idea of the crossing angle. 

Mistakes? Several I'm sure. One being a mismatch between timber thicknesses which results in a step down from the plain track to the turnout. You may notice a broken slide chair propping up the rail to alleviate this (it doesn't). I have a feeling this may be due to a disparity in the foamboard layer the plans are glued to now I think about it. Next time I'm going to invest in a proper crossing jig because this was a nightmare to hold in alignment whilst the solution took hold. 

I have tested it with P4 wheelsets, fine. OO regauged wheelsets, some binding occurs as expected. All other wheels work well. 

Will spend some quality time fretting over how to wire it all up and add a tiebar and convert a loco and watch it crash though my handiwork. At least this will only be a fiddle yard. 

Onwards

 

IMG_5560.jpg

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  • 2 weeks later...

Another sliver of progress as the heel of the turnout is mainly complete. Seeing as it's 0.8mm flangeways I test with 3 different wagons. One with P4 wheels, two with Gibson 00 wheels all at the same B2B

This works. I like it. Just tiebar, throwing and wiring to to do....and something to test it with

IMG_5900.jpg

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12 hours ago, ianb3174 said:

Another sliver of progress as the heel of the turnout is mainly complete. Seeing as it's 0.8mm flangeways I test with 3 different wagons. One with P4 wheels, two with Gibson 00 wheels all at the same B2B

 

Hi Ian,

 

Looking good. smile.gif

 

For best results the P4 wheels should be at a wider back-to-back than Gibson. Assuming EM-SF 18.0mm gauge with 0.8mm flangeways:

 

Gibson wheels: back-to-back: 16.6mm max (same as for regular EM).

 

P4 wheels: back-to-back 16.8mm  max.

 

For the best running wheels should be set as close as possible to the maximum back-to-back, without exceeding it. The object of the exercise is to ensure that when one wheel is running with the flange against the rail head, the back of the other wheel just barely kisses the check rail, but does contact it.

 

Strictly speaking, P4 loco wheels (2.0mm wide) should be ok on EM-SF, but P4 wagon wheels (1.7mm wide) are a fraction too narrow. More about that at:

 

 http://85a.co.uk/forum/view_topic.php?id=3478&forum_id=1

 

cheers,

 

Martin.

Edited by martin_wynne
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Physics and dynamics don't scale so a prototype picture doesn't really help (especially one from another country).  4mm frames don't flex, wheel hunting is different, the forces are completely different.  We are trying to represent the visual appearance and get a model loco to appear to behave like the full size one (though we can never get the vertical flexing of the rail.)  To that end I'll take the evidence of videos of models running well, or the assertions of modellers as good enough, even if figures appear that "prove" this to be impossible.

 

Alan 

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7 minutes ago, Buhar said:

though we can never get the vertical flexing of the rail

 

Never say never.

 

rear: Exactoscale code75 steel bullhead rail.

 

front: Home-3D-printed approx-BS-95R rail in toughened PLA+ polymer.

 

2_111752_390000002.jpg

 

2_111752_390000001.jpg

 

For battery-power+radio control. When supported at typical timber centres, it's just possible to detect some vertical deflection of a thou or two under a well-weighted 4mm model.

 

Filament-printing GCODE exported directly from Templot (no slicer needed). Coming soonish -- or eventually. smile.gif

 

Martin.

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Can't help feeling that something is missing after reading this last night. Anyhow, I've made the necessary tweaks to the BB dimensions and tested it further. I can report zero wheel drop in any configuration, smooth running (up at least 10% from previous estimates) and a sense of achievement that I've made something quite dimensionally critical and done it reasonably well. Hurrah for modelling track I say

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