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Hornby 4th radius curves with larger coaches


simon b
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Simon, even putting a simple curve on an incline includes a certain amount of distortion of the track.  To see what I mean, put together 180 degrees of set-track curves, lift one end 3 inches, and see how much the ends of the curve are canted.  Introducing points magnifies the problem, and a double junction on an incline would be a nightmare.  On a 1 in 100 you might get away with it, but on a 1 in 20?  Not to mention that set-track curved points have a dubious reputation for derailing (I don't have any personal experience), and people frequently remark that they must be laid perfectly flat ......

 

Sorry, but I'm afraid it won't fly in that space.

 

Chris

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So not wanting to give up on this idea just yet, I had a play around with the return loop on the lower level. Using a pair of peco y points (sl97) and a short crossing (sl93) I got to this:

 

20200709_003821.jpg.4377afd9e7931aba64bb64cf0b2fbfaa.jpg

 

20200709_003746.jpg.b0c8c6c2639c1d81e4f2c8461fa73775.jpg

 

That plywood board is 6ft long, and measuring the width at 4ft I managed to get a 3rd and 4th radius loop along with a short 2nd radius inside. The geometry of the tracks at the bottom of the pic doesn't line up, but flexi track should fix that. Those Y points are about a 3rd radius curve so not too tight, however they do introduce a kink which doesn't flow quite right. I cant think of another option though if I want a double loop....

 

Now the next problem is the steepness of the incline heading up to the station, if we can figure out how to overcome that it looks like it might work.

Edited by simon b
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On 09/07/2020 at 02:24, simon b said:

So not wanting to give up on this idea just yet, I had a play around with the return loop on the lower level. Using a pair of peco y points (sl97) and a short crossing (sl93) I got to this:

 

20200709_003821.jpg.4377afd9e7931aba64bb64cf0b2fbfaa.jpg

 

20200709_003746.jpg.b0c8c6c2639c1d81e4f2c8461fa73775.jpg

 

That plywood board is 6ft long, and measuring the width at 4ft I managed to get a 3rd and 4th radius loop along with a short 2nd radius inside. The geometry of the tracks at the bottom of the pic doesn't line up, but flexi track should fix that. Those Y points are about a 3rd radius curve so not too tight, however they do introduce a kink which doesn't flow quite right. I cant think of another option though if I want a double loop....


Could I make a suggestion?  I’d have the loops arranged differently.  This diagram was drawn for a different setting and would need to be shortened to fit the 6’ you have, but illustrates the thinking (dimensions in this sketch were in mm, sorry):

 

(Sorry - photo no longer available)

 

The key thing is that it takes out the crossover and thereby ensures that trains entering the loops on the Down line come out on the Up line.  If there is a crossover it means trains return on the line they came from. 
 

(Edit - forget what I wrote - the crossover as shown by Simon does work correctly for double track lines: I was wrong, sorry.  In my version all trains go round the loop the same way, which I’d suggest may be easier for hidden staging tracks.  I suspect it is easier to fit in, as the point work is simpler, but my initial post was incorrect, sorry).

 

Personally I would think carefully about squeezing in a third loop line because it shortens the second line as well, and adds hidden points on your lower level.  On the positive side, an end curve is longer than it looks: I think a 180 degree 3rd radius curve is about 5’ long (do check my maths), so it’s possible to store two shorter trains on the same track of a loop if you need to.

______________


On a slightly different note, there are plenty of track plans around that fit into this kind of space with reversing loops and steep gradients - but do be careful: many were drawn long before 4th radius (or even 3rd radius) curves became standard, so they assume tighter curves and shorter trains (sometimes with shortened carriages), and with locomotives that might have been coarser, but by all accounts could have tremendous pulling power - sometimes assisted by traction tyres, or a system I think was called magnahesion (or something like that).  If there’s a way of running some climbing / pulling tests with the stock you want to use it may be helpful.  Contemporary r-t-r rolling stock is incredibly detailed, but sometimes assumes a gentler world.

 

 Keith.

Edited by Keith Addenbrooke
Edited for text only as photo no longer available
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23 hours ago, Chimer said:

Well it sort of fits using second and third radius curves, but the crippler is only having at best 5 feet for the incline.  The double reversing loop is a no-no (I've left the diamond in but the inner loop can't connect).  And I don't think the think the third upper right loop is possible, even with first radius curves .......

 

163938125_simonjpg.jpg.a66812c8967ebd21f49f8a14689b0eec.jpg


I think there is a way to address this (the short incline) - I’ll try and sketch it up later.

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OK.  I've had a bit of time at lunchtime today to sketch out an idea - (I have 8' x 4' templates in my Anyrail file for a quick start).  The key idea is to lengthen the mainline between the levels. 

 

It will involve more carpentry, and add weight and height, factors to bear in mind if it ever needs to be moved at all.

 

I've assumed the operator is south of or below the baseboards as drawn, (with access possible to the other sides).  All points are Peco Streamline Medium or Curved (plus one Single Slip).  The Lower level can look like this:

 

(Sorry - photo no longer available)

 

Shaded area 'A' is flat at Datum 0".  The gradient begins at 'B' and climbs gently round the compound end curve to 'C' then steepens along the straight to 'D' - by which point it needs to be high enough to clear 'A'.

 

The main line continues to climb onto the Upper level at 'E'.  The shaded area 'F' is again flat and is the Upper Level. 

 

(Sorry - photo no longer available)

 

This version shows the Upper Level as a terminus for an out and back scheme.  @Zomboid is the person to talk to about operating this kind of layout - with a longer mainline and staging loop at the lowest level trains will look / feel like they've gone somewhere before returning (as different services).

 

I've not spent any time refining the layout of this station, but a couple of things I've built into the sketch:

 

1.  There is a small Goods Depot, primarily for van traffic.  It is shunted on a 'kickback' siding so everything is level, and the sidings themselves are in easy reach of the front of the baseboard for uncoupling.  Focus is on passenger trains.

2.  Arrivals and Departures are separate - with loco hauled stock a Station Pilot will be needed.  This engine will always be 'downhill' of the carriages, preventing 'run-aways'.

3.  The additional crossover from the Parcels Bay is to help shunting from the Arrivals Platform by keeping it all further away from the top of the Gradient.

4.  I have't drawn in any Loco Facilities, but they are deliberately within easy reach.

 

A grade separation diagram looks like this:

 

(Sorry - photo no longer available)

 

The key thing is that the grade is spread out - it is a longer climb but hopefully a gentler one.  I haven't tried calculating the gradient, for two reasons:

 

1.  As has been pointed out previously, the gradient is different on the inner and outer main lines.  However, the 'downhill' line is on the inner (steeper) line - as in your own sketch.  The 'uphill' line has a gentler gradient and curves.

 

2.  A lot depends on the thickness / construction of your upper level baseboard and roadbed.

 

The spin off benefit of this plan is greater clearance for access to the return loop at ground level if needed.

 

An alternative Upper Level with a Return loop could fit, allowing continuous running.  

 

(Sorry - photo no longer available)

 

Note: the Engine Sidings as shown here are not in easy reach.  Carriage sidings are between the platform lines, which was common in the early days of railways, but latterly perhaps best known at Bath Green Park.  Trains remain short.

 

One way that used to be suggested for building plans like this (particularly in American Model Railroading) was to use an open framework that supports the different levels and the gradient in between - not a solid baseboard.  I think this only really works if the layout can be permanently sited somewhere during construction and use.

 

I hope this helps - it's just an idea and I haven't tried calculating or testing the gradients to see how feasible it is.  Keith.

Edited by Keith Addenbrooke
Edited for text only as photo no longer available
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Keith's idea has the great advantage of not having any pointwork on an incline.  Rough calculations as follows:

 

The minimum clearance height (lower baseboard top to upper (unframed) baseboard/trackbed bottom is around 55mm (Hornby Jinty sitting on Code 100 track with no underlay).  Say 6mm for the trackbed, giving an absolute minimum rise from B to D of 61mm (the woodworking would need to be very accurate to get away with that).  Average radius of outer curve B-C say 550mm, so length B-C is ~1300mm (3/4 PI x Radius), and C-D is ~920mm.  Average grade from B-D therefore 1 in 36, of which just over half needs to be at the gentler angle.  No allowance has been made for the transition from flat to inclined.

 

D-E is ~1080mm, making the average grade from C-E 1 in 32, with just about half at the gentler angle at this side.

 

Giving adequately braced support to the upper terminus baseboard would take careful planning.  A conventional 2" x 1" frame adds 50mm to the required clearance and would clearly make things impossible.

 

Though from distant memory, Tri-ang's risers used to gain about half an inch over a 7 inch Series 3 straight, so 1 in 14 (!), and a 3 coach Flying Scotsman would romp up it - but fings ain't wot they used to be traction-wise ......

 

Best of luck ....

 

 

Edited by Chimer
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2 hours ago, Chimer said:

D-E is ~1080mm, making the average grade from C-E 1 in 32, with just about half at the gentler angle at this side.

 

Because of the requirement for clearance above point C and below point D, if the upper board is set at the minimum clearance height, then BC and DE must actually be level, with all the height change occurring between C and D (this is quite easy to see on @Keith Addenbrooke's gradient profile above). With figures as in @Chimer's post this gives the gradient along CD as ~1 in 15...

 

Counterintuitively, raising the upper board a bit actually allows you to ease gradient CD by introducing gradients along BC and DE.  It's then a trade off between how much extra height you add and how you divvy up the gradients, but I found that 30mm is needed to get CD down to 1 in 30, with BC  ~1 in 40 and DE ~1 in 35. This was the best I could do, as more extra height just makes the curved sections steeper.   Again, this is without any allowance for transitions between gradients. 

 

 

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7 hours ago, Flying Pig said:

Counterintuitively, raising the upper board a bit actually allows you to ease gradient CD by introducing gradients along BC and DE.  It's then a trade off between how much extra height you add and how you divvy up the gradients, but I found that 30mm is needed to get CD down to 1 in 30, with BC  ~1 in 40 and DE ~1 in 35. This was the best I could do, as more extra height just makes the curved sections steeper.   Again, this is without any allowance for transitions between gradients. 


I think that’s what I was trying to demonstrate, thank you: as you raise or lower the upper board the gradient profile stretches or squashes to fit, with section CD literally caught in the middle.


Taking @Chimer’s calculation for the radii / track lengths and working out the additional headroom as you have here gives the basis for an answer to test out I think.  As a reference, I think the Lickey incline is something like 1 in 37.

 

This is all I have time for on this, I’m afraid, but hopefully it’s of some use.  I wasn’t able to suggest a scheme which kept a visible junction on the lower level, but CF is all visible and DE has a transition curve which could be a good photo spot?
 

I just hope this isn’t where we find out @simon b needs to include OHLE...

Edited by Keith Addenbrooke
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On 09/07/2020 at 14:48, Keith Addenbrooke said:

OK.  I've had a bit of time at lunchtime today to sketch out an idea - (I have 8' x 4' templates in my Anyrail file for a quick start).  The key idea is to lengthen the mainline between the levels. 

 

It will involve more carpentry, and add weight and height, factors to bear in mind if it ever needs to be moved at all.

 

I've assumed the operator is south of or below the baseboards as drawn, (with access possible to the other sides).  All points are Peco Streamline Medium or Curved (plus one Single Slip).  The Lower level can look like this:

 

345073333_LowerLevel.jpg.86315f4c811ecd69da93dab90cc9f6be.jpg

 

Shaded area 'A' is flat at Datum 0".  The gradient begins at 'B' and climbs gently round the compound end curve to 'C' then steepens along the straight to 'D' - by which point it needs to be high enough to clear 'A'.

 

The main line continues to climb onto the Upper level at 'E'.  The shaded area 'F' is again flat and is the Upper Level. 

 

1458187303_UpperLevel.jpg.05474d4cd3138b0c9030512007131814.jpg

 

This version shows the Upper Level as a terminus for an out and back scheme.  @Zomboid is the person to talk to about operating this kind of layout - with a longer mainline and staging loop at the lowest level trains will look / feel like they've gone somewhere before returning (as different services).

 

I've not spent any time refining the layout of this station, but a couple of things I've built into the sketch:

 

1.  There is a small Goods Depot, primarily for van traffic.  It is shunted on a 'kickback' siding so everything is level, and the sidings themselves are in easy reach of the front of the baseboard for uncoupling.  Focus is on passenger trains.

2.  Arrivals and Departures are separate - with loco hauled stock a Station Pilot will be needed.  This engine will always be 'downhill' of the carriages, preventing 'run-aways'.

3.  The additional crossover from the Parcels Bay is to help shunting from the Arrivals Platform by keeping it all further away from the top of the Gradient.

4.  I have't drawn in any Loco Facilities, but they are deliberately within easy reach.

 

A grade separation diagram looks like this:

 

760650236_Levelseparation.jpg.ff0153e72b0127280a07dddce328961d.jpg

 

The key thing is that the grade is spread out - it is a longer climb but hopefully a gentler one.  I haven't tried calculating the gradient, for two reasons:

 

1.  As has been pointed out previously, the gradient is different on the inner and outer main lines.  However, the 'downhill' line is on the inner (steeper) line - as in your own sketch.  The 'uphill' line has a gentler gradient and curves.

 

2.  A lot depends on the thickness / construction of your upper level baseboard and roadbed.

 

The spin off benefit of this plan is greater clearance for access to the return loop at ground level if needed.

 

An alternative Upper Level with a Return loop could fit, allowing continuous running.  

 

606161705_UpperLevel2.jpg.cc495457d0b0ad2fd34047fa92ea1871.jpg

 

Note: the Engine Sidings as shown here are not in easy reach.  Carriage sidings are between the platform lines, which was common in the early days of railways, but latterly perhaps best known at Bath Green Park.  Trains remain short.

 

One way that used to be suggested for building plans like this (particularly in American Model Railroading) was to use an open framework that supports the different levels and the gradient in between - not a solid baseboard.  I think this only really works if the layout can be permanently sited somewhere during construction and use.

 

I hope this helps - it's just an idea and I haven't tried calculating or testing the gradients to see how feasible it is.  Keith.

 

Thank for taking the time to work all that out, certainly very helpful.

 

I do like the second plan as the ability for a continuous run is a must with this layout, that way the operator can sit and watch trains run by or operate it as an out and back layout.  The junction on the lower level was my attempt at masking the fact they are return loops by having trains run around them in both directions, if the loops are completely hidden like your plan it would no longer be an issue. I think I'll leave the crossing out and just have 3 loops on the lower level as long as I can make them. 

 

The upper level with the station inside the return loop is definitely how I want it to go, though I might move the loco depot to the space inside the mainlines and access it via the upper return loop.

 

I'll have a play around with the space on the upper section and see what fits, though please don't tempt me with OHLE or I'll try to fit Euston on the upper section!

 

Ta.

Edited by simon b
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The upper return loop really cramps the station though - absolute maximum two coach trains.  And you could do with the second (opposing) crossover in the throat pointwork to let trains depart from both platforms and the goods yard, though I know Keith's plan is just indicative ......

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4 hours ago, simon b said:

The upper level with the station inside the return loop is definitely how I want it to go, though I might move the loco depot to the space inside the mainlines and access it via the upper return loop.

 

This version changes the gradients because the top board is wider and so the section CD is shorter.  The effect is to make CD and DE steeper than 1 in 30 in all the variations I tried.

 

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Whilst that's coming along nicely, and probably represents the best option, another "legacy" plan which might be worth a look, if you can find a copy, appeared in RM as Railway of the Month c1970 or so. It was titled For Amusement Only (IIRC) and was a most intriguing series of loops and gradients, allowing out and back or continuous running. The terminus was a bit short, admittedly, but the club who built it seemed very happy with it. It was (again IIRC) 8'x4'6", so fractionally bigger than the target. However, it does have the advantages of being proven as buildable/workable, and, again if you can track down the back issue concerned, has been well photographed so you can see what a new version might look like. 

 

Edit: A brief search says it was the December 1971 issue and the layout was built by the Saffron Walden MRC. Given the broad reach and comprehensive knowledge displayed by RMWeb, it would not surprise me if someone here had firsthand experience of it. 

Edited by PatB
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I took you guys advice and had a play around with the free version of anyrail, it limits me to 50 track peices so I've not included freight or loco sidings on this attempt.  The return loop around the station is 3rd radius, so that should leave enough base board width to get the mainlines to drop down behind it. It's not the most realistic arrangement of pointwork but should be workable for what I need to do, and give me 4ft or more for the platform lines.

 

My rough working out puts the distance between the tunnel exit from the lower level, to the start of the station throat as 9 feet. So that's 108", divided by 3 for the height I need to get, gives me a grade of 1 in 36 if I did my math correctly. Does that sound workable?

252714257_Screenshot(108).png.71c5e61cc73e300286b5eaa41a1c4289.png

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Is 3" enough clearance is the obvious first question.

 

What will perform on a 1:36, 180* 3rd radius curve is another. I imagine there will be suitable models out there, my Atlas RS11 would probably take a fair few freight cars up there, but on the other hand I doubt my Bachmann USA Russian Decapod would be able to climb it light engine.

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2 hours ago, Zomboid said:

Is 3" enough clearance is the obvious first question.

 

What will perform on a 1:36, 180* 3rd radius curve is another. I imagine there will be suitable models out there, my Atlas RS11 would probably take a fair few freight cars up there, but on the other hand I doubt my Bachmann USA Russian Decapod would be able to climb it light engine.

 

I came to the 3" height measurement from the average height of a 00 loco sitting on code 100 track, with a 9mm baseboard above it I'm left with a gap of 6mm between them. In all other places I would have more height than that, but the tunnel entrance under the upper level is where it is tightest. Once in the tunnel however, the track drops further by another inch or more, so things are more generous.

 

It would be possible to get more than the 3" at the tunnel entrance by raising the upper return loop slightly in that area, the terminus tracks would be unaffected as they are further on down the grade. Perhaps another 5-10mm would be possible by doing that.

 

I think the grade itself wont be too much of a problem for the locos to climb, the stock that will be mostly used on it are old Hornby and Lima items with traction tyres. I remember from when I was younger putting some ridiculously long trains behind some of these just running on the carpet, though I would imagine that some newer items without traction tyres would have less grip on the slope.

 

The problem I have now is that I cant lessen the grade anymore without compromising the station length on the upper level, using compound curves as Keith has suggested will help but I think that is as shallow as It can go.

Edited by simon b
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11 hours ago, simon b said:

Does that sound workable?

 

Sorry no, it's still more complicated because the gradient is still in three sections with clearance requirements as above.  However, the tricky bit is now keeping the gradient CD down without making the bottom section BC very steep.

 

Looking at the plan though, I see no reason why the start of the gradient shouldn't be moved right back into the loops which not only adds about 1000mm to section BC, but puts the transition on straight track.

 

Doing this and with the same heights as before (61mm clearance plus 30mm extra) the easiest gradients I can get are:

 

BC 1 in 60

CD 1 in 40

DE 1 in 45

 

That's still a lot of hidden track with very limited clearance above it.  Combine that with the very short terminus and tbh I'm struggling to see the advantages of this plan compared to a simple roundy roundy.

Edited by Flying Pig
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1 hour ago, Flying Pig said:

 

Sorry no, it's still more complicated because the gradient is still in three sections with clearance requirements as above.  However, the tricky bit is now keeping the gradient CD down without making the bottom section BC very steep.

 

Looking at the plan though, I see no reason why the start of the gradient shouldn't be moved right back into the loops which not only adds about 1000mm to section BC, but puts the transition on straight track.

 

Doing this and with the same heights as before (61mm clearance plus 30mm extra) the easiest gradients I can get are:

 

BC 1 in 60

CD 1 in 40

DE 1 in 45

 

That's still a lot of hidden track with very limited clearance above it.  Combine that with the very short terminus and tbh I'm struggling to see the advantages of this plan compared to a simple roundy roundy.

 

Ah, I had assumed that from the exit of the lower loops up to the tunnel portal was BC, and the tracks would rise by 25-30mm over the 1000mm or so length. The 1 in 36 grade I mentioned was only including CD and DE, but was the average I got from the 9 feet length of that section.  

 

My thinking was that the points on the lower level before the start of the climb at A, would be 100mm lower than the track level at E? If your saying that the grade at C-D can be 1 in 40 that's better still.

 

My working out makes the total length of the climb around 12 feet including BC, CD, and DE. So that's 144" divided by 4 for the height difference gives me an average of 1 in 36 again.

 

I know it's a lot of messing about, but I prefer this plan to the normal oval as the trains have much more of a run. And also they appear to be going somewhere rather that just round in a circle,  the storage loops being out of sight is a big bonus for me.

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As I understand it, Simon's latest plan goes away from Keith's clever 3 stage incline and back to basics with a straight climb from tunnel portal to throat, all in view.  I thought it was worth checking that the low level return loop fitted and it does, though I did need to sneak in 45 degrees of second radius on each of the return loops to keep them clear of the gradient.  Pink is lower level, blue upper and green the gradient, which I've measured at 94" from portal to throat, so closer to 1 in 30.  I've left a couple of set-track discontinuities in the bottom right hand corner on the upper level.  I've also managed to enable simultaneous arrival and departure at the terminus at the cost of slightly shorter platform roads, but I'm not convinced it's worth it.  And I don't think you'll be able to do much in the way of extra loops on the lower level - maybe one inside the straight across the bottom (which is directly below an upper level track).

 

1936624282_simon2jpg.jpg.89ede288f7557dbf6a4470cd91cdf8bd.jpg

 

Good luck!

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1 hour ago, Chimer said:

As I understand it, Simon's latest plan goes away from Keith's clever 3 stage incline and back to basics with a straight climb from tunnel portal to throat, all in view.  I thought it was worth checking that the low level return loop fitted and it does, though I did need to sneak in 45 degrees of second radius on each of the return loops to keep them clear of the gradient.  Pink is lower level, blue upper and green the gradient, which I've measured at 94" from portal to throat, so closer to 1 in 30.  I've left a couple of set-track discontinuities in the bottom right hand corner on the upper level.  I've also managed to enable simultaneous arrival and departure at the terminus at the cost of slightly shorter platform roads, but I'm not convinced it's worth it.  And I don't think you'll be able to do much in the way of extra loops on the lower level - maybe one inside the straight across the bottom (which is directly below an upper level track).

 

1936624282_simon2jpg.jpg.89ede288f7557dbf6a4470cd91cdf8bd.jpg

 

Good luck!

 

Sorry if I misled you, I'm not always that great explaining what I want to do. 

 

I'm keeping the 3 stage incline, the grade starts at the beginning of the return loop on the lower level and ends at the throat pointwork. My measuring makes it 144" length to do that in, with a slightly sharper grade to clear the loops underneath. I referred to the tunnel portal alot as that seems to be the part where clearance will be at it's least. 

 

I did try to get more flexibility with the throat as you have, but whatever I tried shortened the platforms or made the climb steeper so I have accepted it as it is. At the moment an N2 with 3 or 4 suburban coaches should be able to fit.

 

The part shown in green on your plan is visible from that side, the left side of the board will be against a wall but all others will be open. So effectively an 8ft island out from the wall. I had thought of making a view blocker from tall buildings across the middle of the board at an angle to separate the station from the climb, so I get a sort of scenic u shape. I've seen some american layouts like that and it looks quite effective.

Edited by simon b
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OK, I can see that continuing to fall from the portal round the pink curve at the left hand side would enable you to push the lower level return loop across to the right hand side of the board, under the last bit of the climb, which gains useful space for a storage loop (or maybe even loops).  Just falling an extra inch round that curve would be enough, which is very gentle (better than 1 in 50).  But as you identified, the key figure comes from the need to climb 3 inches between portal and throat. 

 

All the best ....

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A quick learning point I discovered around platform and train lengths is that, if using uncoupling ramps of any kind, they can effectively shorten the available length of track, as all commercially available ones (that I’m aware of) sit in straight track, whereas trains and platforms bend.  Hence to get an coupling (say between arriving loco and train, or between pilot and train)  in the right place, may mean more space is needed than what is physically dictated by train length.

 

Also, what Anyrail doesn’t obviously factor in (So you must manually calculate) is the height of track bed and rail on lower level (say 4-5 mm), not to mention underboard bracing frame of upper levels. I know from personal experience that when you get to be working in such tight margins, it’s easy to make a mistake. One loco of mine cannot use one lower track simply because a screw head of upper frame needed another turn to go up and in a shade further - but I couldn't access it to do so.

Edited by ITG
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Sorry, I found I couldn't leave it alone ...... I've sorted the discontinuities, added a couple of loops at the lower level and played around with the terminus area to include a bit of a goods yard with a run-round and a loco servicing siding.  The red labels (0/3.3, etc) give the elevations of the tracks where they cross over one another.  The grade inside the tunnel is 1 in 50, and the rest 1 in 33.

 

12809387_simon3jpg.jpg.52c22ac4b80ab2bcf477edda09a93667.jpg

 

All yours!

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Nicely done, Chris.

 

I'm still worried about the practicality of it in the real world, though.

Have you allowed for transitions from level to grade and back to level again?

I suspect trains will be prone to stalling and derailing somewhere near the 0/4 mark on the right - especially 6 and 8 coupled steam locos. That's because of the change from helix to level leading directly into curved points.

 

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You're probably right ...... I mentioned transitions as an issue a while back, I was just playing about to see what can be done within the parameters Simon seems happy to accept, and getting the basic grade data out of X-TrackCad.

 

Cheers, Chris

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