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Re6/6

Unusual PW configurations thread both real and model.

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Trams are always good for unusual pointwork. I was impressed with this arrangement in Ghent: http://goo.gl/jtW7d1

 

Maybe not that unusual individually, but it's a bit much when you consider that outside slip and double lead junction all are for a bit of tramline that no longer exists!

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Maybe a little OT, so with John's forbearance, could somebody please explain to me in idiot's terminology, the difference between inside and outside slips?

TiA

 

Ed

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I do like the fourth down in the photoset. Looks like it's a case of "Oh buffer! How do we get round THAT corner?"  The answer by the track laying foreman was "Like this guv!!"

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That sort of "over and back" curve is not unusual in tramway practice when trying to negotiate old street layouts.

 

Jim

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I do like the fourth down in the photoset. Looks like it's a case of "Oh buffer! How do we get round THAT corner?"  The answer by the track laying foreman was "Like this guv!!"

Oh yes, that's what's going on, it wasn't that there was a car parked there when they were laying the track :D

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Maybe a little OT, so with John's forbearance, could somebody please explain to me in idiot's terminology, the difference between inside and outside slips?

TiA

 

Ed

 

A 'normal' slip (compound)  point 

post-6728-0-75609400-1423131331.jpeg

 

A semi-outside slip 

post-6728-0-78804300-1423131663_thumb.jpg

 

A 'full' outside slip (can't find a pic!) is where all the curved rails are totally outside the diamond crossing.

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...A 'full' outside slip (can't find a pic!) is where all the curved rails are totally outside the diamond crossing.

Surely, if all the curved rails are outside the diamond, you just have a scissors crossing? It makes no difference whether the outer routes are straight or curved, the form is the same. I must admit, though that I don't recall seeing a scissors in which the outer routes have opposite curvature.

 

Nick

Edited by buffalo

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Surely, if all the curved rails are outside the diamond, you just have a scissors crossing? It makes no difference whether the outer routes are straight or curved, the form is the same. I must admit, though that I don't recall seeing a scissors in which the outer routes have opposite curvature.

 

Nick

Not true. An outside double slip has a similar layout to a scissors crossover, the difference being that 2 parallel routes cannot be set up at the same time for trains to pass. I've never seen one, but Wikipedia shows one.

 

http://en.wikipedia.org/wiki/Railroad_switch#Outside_slip

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Not true. An outside double slip has a similar layout to a scissors crossover, the difference being that 2 parallel routes cannot be set up at the same time for trains to pass. I've never seen one, but Wikipedia shows one.

 

http://en.wikipedia.org/wiki/Railroad_switch#Outside_slip

 

What's not true? That photo at Heidelberg is just the extreme case of an outside slip as shown in John's second photo. The only difference is that the inside rails of the two outer routes are adjacent. It is not the case that john describes as "all the curved rails are totally outside the diamond".  Yes, in any double slip the two outer routes cannot be used at once, but if "all the curved rails are totally outside the diamond", you have a scissors crossing and they can provided there is enough lateral clearance.

 

Nick

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Aren't slips (all slips) fundamentally diamonds where as scissors are fundamentallly parallel tracks? They both have extra rails and complication, but that seems to be the main difference.

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No need for confusion, John, The photos in your post shows a normal or inside double slip and an outside double slip. Nothing 'semi' about it, it's a 'fully' outside slip. I believe the 'semi' term has been used to describe a double slip where one side in inside and the other outside, though I don't know of an example. As I understand it, the inside/ouside distinction describes whether the point blades are inside or outside the diamond.

 

Nick

Edited by buffalo

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. As I understand it, the inside/ouside distinction describes whether the point blades are inside or outside the diamond.

 

Nick

 

That makes sense. I was thinking about the curved route being inside/outside the point. Thanks Nick

 

Ed

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What's not true? That photo at Heidelberg is just the extreme case of an outside slip as shown in John's second photo. The only difference is that the inside rails of the two outer routes are adjacent. It is not the case that john describes as "all the curved rails are totally outside the diamond".  Yes, in any double slip the two outer routes cannot be used at once, but if "all the curved rails are totally outside the diamond", you have a scissors crossing and they can provided there is enough lateral clearance.

 

Nick

What's not true? Is your earlier suggestion (Post 9) that an outside slip & a scissors crossover, is the same thing.

 

A scissors crossover can have 2 trains pass, (on the straight(ish) tracks- I don't think the tracks have to be straight), that isn't possible on an outside slip (or any slip for that matter).

 

I'm sure Martin Wynne, will be along soon to correct any misinformation, with examples of the differences.

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What's not true? Is your earlier suggestion (Post 9) that an outside slip & a scissors crossover, is the same thing...

 

Why not read what I said and stop putting words into my mouth?

 

Surely, if all the curved rails are outside the diamond, you just have a scissors crossing?

In other words, if all the curved rails are outside the diamond, you do not have a double slip. The "all the curved rails..." bit was from John's post where he said

 

...A 'full' outside slip (can't find a pic!) is where all the curved rails are totally outside the diamond crossing.

Nick

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Not exactly a 'formation' but a little novelty to consider - speed humps for rail vehicles. Brian

post-5773-0-54362800-1423148686_thumb.jpg

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Not exactly a 'formation' but a little novelty to consider - speed humps for rail vehicles. Brian

 

Where on earth was that Brian?!

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Where on earth was that Brian?!

The old docksides Ipswich, John. I don't actually see the why or how of it or what real purpose it served. An apprentice piece perhaps. Brian.

 

Just thought, it's probably a track scotch block type thing that cars can drive over. B

Edited by Brian Harrap

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The old docksides Ipswich, John. I don't actually see the why or how of it or what real purpose it served. An apprentice piece perhaps. Brian.

 

Just thought, it's probably a track scotch block type thing that cars can drive over. B

It does look as if it might once have been movable judging by those adjacent gaps full of muck - maybe it rotated???

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From the look of the two sections that are across the rails, there might be an associated operating lever that moves them into the gaps to their right in order to allow rail traffic to pass...

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This is only a single of course, but it must be a half inside, half outside slip. None of it straight either. Brian

post-5773-0-79029100-1423247670.jpg

Edited by Brian Harrap
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Showing the West end of platforms 16 & 17 at Clapham Junction looking towards the Brighton Slow lines (a goooood long while ago)............................. ???

 

Banking / pilot engine release siding for trains coming up from the WLL ??

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