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> Parallel track separation measurements
M8 INTERNET
post 28 Apr 2010, 08:12
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I used to have a template that had the track separation for Peco Streamline
However, I noticed yesterday that I had disposed of it, before taking measurements!

I have placed two large and two medium with straights in order to try and recalculate the separation required for parallel tracks
The measurement has come out at 25mm
However, on placing my Peco 6' way gauge I notice the separation is 27mm
I therefore assume the 27mm is correct?

I assume the difference of 2mm is caused by the points not being perfectly aligned, even though I did it with all four types (ie medium left-left, medium right-right, large left-left, large right-right)

Now the second problem
I noticed when visiting some of the passing loops on the WCML last week that there is extra separation allowance for the catenary masts
Does anyone have measurements for the minimum distance between rail and a Mark 3 catenary mast?
http://www.nbrasslocos.co.uk/KitImages/CSmk3.gif
Obviously this isn't an issue where full track width supports are used (although I've yet to find a manufacturer of this type)
http://www.trainspots.co.uk/500-599/sandy/...viewslow-pm.jpg
However, I have noticed many of these are being replaced by the light weight portal (as used on the WCML)


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John Webb
post 28 Apr 2010, 10:00
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The Peco catalogue shows 26mm to the inside of the adjacent rails of each pair so allowing for the thickness of the track your 25mm is probably correct.

Regret I can't give any information re the spacing of masts from the track.

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John Webb
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Putzi
post 28 Apr 2010, 10:45
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You could perhaps try using the MOROP NEM standards, rescaled from 1:160 to 1:148, although I'm not sure how they work with track that should ideally have a gauge of 9.729mm... wink.gif

QUOTE (M8 INTERNET @ 28 Apr 2010, 09:12) *
I noticed when visiting some of the passing loops on the WCML last week that there is extra separation allowance for the catenary masts
Does anyone have measurements for the minimum distance between rail and a Mark 3 catenary mast?

I would have thought that the only places you'll get that sort of highly detailed information from is: actual measurement of prototype (illegal?), the design plans or designers, or from measuring in a photograph by using the rail gauge as a scale. I used this last method to work out real-world Austrian track spacing from a photo to check the NEM recommendations. It's very easy to count the pixels.


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M8 INTERNET
post 28 Apr 2010, 11:33
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QUOTE (Putzi @ 28 Apr 2010, 11:45) *
I would have thought that the only places you'll get that sort of highly detailed information from is: actual measurement of prototype (illegal?), the design plans or designers, or from measuring in a photograph by using the rail gauge as a scale

I do have some reference material for this, I just need to find it!

One issue with "pixel measuring" is that on the WCML very little track is straight, so any measurement would only be an approximation, plus the distance would take into account any curve

There are two passing loops on the WCML between Carstairs and Carlisle that are reasonably straight, but access would be an issue
Taking a remote measurement wouldn't be an issue, I have equipment for that
Equally, the masts should have a plate on them with the distance to the nearest rail!

Looks like this might just have to wait until my next visit of those locations


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Edwin
post 28 Apr 2010, 13:18
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If you look on the Rail Regulator website www.rail-reg.gov.uk you'll find the principles and guidance which are descended from the old "blue book". This gives a range of minimum clearances and you could probably work out the minimum permitted for tracks separated by a mast.

I've laid my track to the Peco Streamline spacing which was about 27.5mm between track centres if I recall correctly. 26mm between adjacent rails sounds too much - is this perhaps the figure for Setrack? On the prototype it is 6' minimum between outside of adjacent rails, which would make the track centres about 22mm in N gauge. Remember also that if there are three or more tracks, including where there is a loop, there will normally be a wider interval on one side or other of each track, and usually this is on the left as seen by drivers of passing trains.

I believe some people lay Streamline to this spacing and shorten the curved bits of points to suit, and I wish I'd done this as my tracks do look a little too widely spaced.
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oscar
post 28 Apr 2010, 16:52
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A lot of info. here, (ignore the warning if you get it, I've just been on!)

http://www.fortunecity.com/business/direct...255/Scales.html
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M8 INTERNET
post 28 Apr 2010, 17:09
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QUOTE (Edwin @ 28 Apr 2010, 13:18) *
I've laid my track to the Peco Streamline spacing which was about 27.5mm between track centres if I recall correctly. 26mm between adjacent rails sounds too much - is this perhaps the figure for Setrack?

I found my template, couldn't seeing it for looking! (Need to take a measurement now)

The 26mm is taken by laying two pieces of flexitrack and then measuring the outside of rail to the outside of rail
This is from the spacers on the lower side, the ones on the upper side look like setrack, but I have a block of wood for that (gap is something enormous like 45mm)

I am wondering if the Peco gauge takes into account plaicing the Streamline track on a curve, as my template has two measurements, straight at one end and at roughly 45' for the clearance on curve


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Edwin
post 28 Apr 2010, 21:58
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I think the Streamline measurement is OK down to about 15" radius, based on using things like Mk3 coaches. Obviously OK on tigher curves for shorter wheelbases.
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M8 INTERNET
post 28 Apr 2010, 22:33
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The curves in my scenic area have very large radius, probably somewhere in the region of 30" or more
There are other curves, but they do not apply to the parallel main line tracks or are hidden out of view

For minimum curves, I have now found the trick is to use a BachFar Class 47/57 and the VGA wagon
Basically if the loco derails then the curve is too tight
Equally, if the VGA wagon derails the curve is too tight (but not necessarily less than 12" radius)
I have 8 tracks (out of 26) in the fiddle yards that cannot use VGA wagons, not an issue as I am now aware of it


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Edwin
post 29 Apr 2010, 06:42
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Yes the VGA is a good one to test curves being the longest fixed wheelbase vehicle I have found. It has an "interesting" response to superelevation as well. The spacing between tracks depends on the throwover at the ends of a coach on the outside of a curve or the middle of one on the inside. For these in British N the worst cases I have found are the Mk3 coach and the Dapol Cargowaggon.
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M8 INTERNET
post 29 Apr 2010, 08:58
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QUOTE (Edwin @ 29 Apr 2010, 06:42) *
Yes the VGA is a good one to test curves being the longest fixed wheelbase vehicle I have found. It has an "interesting" response to superelevation as well

I though about superelevation, but after calculating the angles and setting up a sample I decided against it
What really surprises me is why BachFar didn't get round this problem in the same way as Hornby (or was it Lima) did for their version by having wheel mouting points that swivelled, albeit not realistic, but sometimes you have to compromise with reality and what is practical sometimes!

QUOTE (Edwin @ 29 Apr 2010, 06:42) *
The spacing between tracks depends on the throwover at the ends of a coach on the outside of a curve or the middle of one on the inside. For these in British N the worst cases I have found are the Mk3 coach and the Dapol Cargowaggon

I was already aware of this from OO gauge models in the 1990s
I tested what the minimum clearance needed to be a long time ago (for streamline), using four Mark 3 coaches with two of each on the adjacent tracks
I also tested with Class 158 and Mark 4 coaches
I do have some Dapol Cargowaggon, but never tested with these, so had better test with these (although I only have five)


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Edwin
post 29 Apr 2010, 11:07
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I think the Hornby/Lima arrangement of one-axle bogies has come in for some stick in the past. I suspect it's a case of not being able to get it right whatever you do.

I'm glad you're basing your clearances on the Mk3 and potentially the Cargowaggon - I think the worst case is a Mk3 on the inside passing a Cargowaggon on the outside of the curve but it's as well to check other combinations too. You were giving the impression that the VGA is the only one you need to use, and I think we are agreed this is wrong.
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M8 INTERNET
post 29 Apr 2010, 12:27
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QUOTE (Edwin @ 29 Apr 2010, 12:07) *
I'm glad you're basing your clearances on the Mk3 and potentially the Cargowaggon - I think the worst case is a Mk3 on the inside passing a Cargowaggon on the outside of the curve but it's as well to check other combinations too. You were giving the impression that the VGA is the only one you need to use, and I think we are agreed this is wrong

I assume you mean the up fast against the down fast lines
This is where the greatest risk of impact is with damage
It's not so bad if up slow and up fast / down slow and down fast trains contact each other, obviously any contact wants to be avoided!

The issue with the VGA is completely different, clearance isn't the issue there, that is curvature and minimum radius
As mentioned previously I have found the VGA operates on a 10" curve, which is typically the minimum I use in the fiddle yards
However, if you have a S-shape curve even with minimum 10" radius then it fails, equally if you have two opposing Setrack points, the VGA also derails
So long as you are aware of these restrictions then you can still use these wagons on your layout
I would rather employ the restrictions and retain these wagons, than not use them at all


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locoworks
post 30 Apr 2010, 16:31
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i think that even the streamline centres are not actually correct and the tracks should be even closer together for true prototype?
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M8 INTERNET
post 30 Apr 2010, 16:36
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Probably, but there has to be a balance between reality and praticality
The streamline separation of 26mm looks better to me than the awful separation of 31mm in setrack


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