Harlequin

EDIT: To Harlequin, I suspect the gradient begins ASAP after the junction. I don't know if that's enough space to dip 3.5" but it's possible.

Hi Quentin, We cross-posted.

Yes, I twigged that after I posted but I'm dubious there's enough room to drop below the baseboard support structure: Say 3000mm @ 1:36 = 83mm drop - probably not enough.

So is the solution an even steeper gradient before the helix with powerbase under both the helix and the gradient? Things are getting even more complicated...

The new larger images are great and I applaud the intention behind a lot of the changes but the big concepts still seem to be all wrong to me, I'm afraid.

Purely technically, there's a huge problem with the position of the helix: Assuming that the lines from the top level start to descend at the tunnel symbols and that the helix uses the minimum gradient, it will take almost a full turn before there's enough clearance above it for any other lines to pass above.

[Edit:] Even if the lines to the helix start descending as soon as they turn away from the platforms in the middle of the design there's probably not enough clearance at the ends of the platforms because of the likely substantial baseboard support depth at that point. (And the transition from a gradient to the helix could be tricky.)

In other words, as drawn the helix lines conflict with the ends of all the platform lines.

The obvious place for the helix is inside the reversing loops.

I think I have the answer!

You could have an O gauge layout on the other side of the shed to counter-balance the N gauge. Motorise the pulley system and automate it so that as a OO gauge train approaches, the N gauge layout rises out of the way and then as the OO train rounds the end of the shed the system reciprocates to raise the O gauge layout out of the way.

Sorry, I couldn't resist.

??? I think the thing that has come out of all this is that the shed is a bit too narrow for what James wants to do. This layout really needs the terminus down the middle of the room (like Clive's). But in 00, that needs a shed at least 12' wide. I don't know if James' land gives him any flexibility.

I keep saying that because if the shed design changes in any significant way then the whole concept of the proposed layout goes out the window and most of this thread will be wasted time.

I know it's a chicken-and-egg situation with shed and layout. If the layout design was rock-solid you could design the shed to match. With no firm layout design I think the best approach is to make the shed generally "layout-friendly" - wide enough for reasonable radii OO curves (realistically that means a circuit around the outside of the room).

Clive's layout is the latest of many previous versions, AFAIK, and he has the luxury of a big square-ish room. Whereas this is James' first since childhood. Different kettle of fish!

CJF designed many layouts where a high-level terminus sits against one wall and the circuit around the room runs partially below it. That seems like a good pattern for limited space.

(BTW: Can you tell that I'm bored at work??? ;-)

@James: Have a look at this thread: http://www.rmweb.co.uk/community/index.php?/topic/78114-dcc-concepts-powerbase/

It describes powerbase being used in conjunction with helices and gives some practical and theoretical info about possible train lengths.

To my eye, though, that sort of thing is just an ugly bodge to solve the symptoms of a problem rather than solving the problem itself.

I can see why a powerbase helix might be needed in existing layouts but adding one to a layout in the design stages is probably the sign of a bad design, IMHO. In the vast majority of cases there must be a better solution.

I suggest you need to think really critically about why you want certain features and the impact they will have on the overall design. Be ruthlessly logical and throw out anything that's difficult to justify.

A good design should hit the sweet spot between form, function and feasibility.

Shed First, though!

Possible construction for a simple lower level:

The idea would be to find a place, or create a place, on the main level where the tracks move away from the edge of the board and inset your underground cutting in that location, as part of the station complex.

The open framework supporting the lower level allows you reach the lower level tracks (with difficulty) and the underside of the main level.

Keep the lower level very simple - little more than a single or double track circuit with any pointwork as near the front as possible for easy access. Probably no track connected to the main level at all.

Adjusted with 2600mm left hand reversing loop and cleaner routes through fiddle yard so that main lines only traverse one facing and one trailing point each.

Note: As drawn, only two of the green storage lines are long enough to hold 36-wagon MGR trains.

The issue I haven't worked out the solution to with that Phil, is if you look at the reversing loop on the left, depending on train length you could hit yourself on the diamond crossing. There's probably an easy solution but it's too early on a Monday right now.

Oh, ah, I didn't think of that but...

I've just measured it and the distance around the loop is ~2250mm at 2mm scale - long enough for 14-15 150mm long vehicles.

Phew!

In post #47 both reversing loops connect the outer to the inner circuit. I.e. the facing point leading to the reversing line is on the outer circuit at both ends.

A small improvement would be to have one of them work the other way so that both the reversing loops have the same effect. I.e. trains heading out of any of the storage sidings in either direction have the choice of running through the station or over a reversing loop. (Better to have the choice on exit from the storage sidings rather than entry so that you don't have to think about reversing a train before you "park" it.)

You could also save some width in the fiddle yard by staggering the storage sidings and that has the advantage that each siding holds one train rather than queuing them up. Trains will never block each other - there's always an exit route. And occupancy detection is much simpler, if you want to do that.

This is 800mm wide at 2mm scale. It just shows the topology - I haven't tried to make smooth curves or smooth turnouts so this would need a bit of finessing to create a real track plan.

@James: I'm sure SIGTECH was not "trolling" or trying to be harmful in any sense.

It's just a bit frustrating for experienced modellers to see you working this through the hard way.

I do lots of planning work but I still find that clause difficult to understand. Not a good example of "plain English".

Yes, indeed!

I read it this way:

• Curtilage is the boundary of the ground that you own, A
• Subtract the area of the house as built or as it was in 1948, whichever is later, H
• Calculate the area of all other relevant structures inside the boundary, including the newly proposed one, measured over their outside walls, C
• If (C > 0.5 * (A-H)) Then permitted development is not allowed

I only mentioned it because James's proposed shed is quite large and his garden is very small (judging by the Shed/Loft thread).

You may need planning permission. See permitted development rules, part E.1.b.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/606669/170405_Householder_Technical_Guidance__-April_2017_FINAL.pdf

Re. separation. Think about reaching in to the back of the lower level to clean the tracks, pick up a derailed train or to solder a wire to the upper level - that sort of thing. And think about the potential damage to delicate scenic items as you do that...

Re. the use of the connection between upper and lower: your mainline traffic won't use it and I guess your dedicated tube-trains won't use it - only the suburban services that you mention. Maybe that's a bigger proportion of your traffic movements than I imagine. Fair enough.

A helix obviously adds complexity. It will take a lot more work to fix it in position, adjust it, set up the in and out transitions, lay track on it, wire it up, etc. And it will be relatively expensive compared to the other baseboards.

If the underground station is intended to be open to the main level in a cutting, why not model it that way, so that it's a more realistic part of the main model rather than a separate entity? Keep the non-scenic underground trackwork as simple as possible, on open baseboards so that you can reach both it and the main level above from underneath. [i'll sketch a section if I get time.]

Re. the underside of the top level: You won't directly see the underside if the top level baseboards from normal viewing angles but the underground station is quite deep so you'll have to get quite a low angle to see the back of it. Then anything descending from the upper baseboard, especially near the front, is likely to be visible. But more than that, the modelled underground will be uncomfortably close to the unmodelled structure of the upper level. There will always be the temptation for viewers to get down low for a closer look and if they then see timber and wires above the illusion will break down.

But I'm mainly worried that all this planning effort might be wasted if the shed can't be created as planned for whatever reason. Shed first.

Iain M Banks was a great loss to Sci-Fi fans and, like you, I've been searching for ways to fill the void.

So many books look promising and then fail to engage in quite the same way as the Culture novels did but two series that come close (IMHO) are:

Alastair Reynolds' "Poseidon’s Children" trilogy

and

Chris Beckett's "Dark Eden" trilogy

The helix and the magnetic traction device simply add to the "complexity" and make this design even less achievable than before!

All of these designs are essentially two separate layouts with a difficult, expensive and rarely used connection between them.

A 30cm separation will still compromise your access to both the lower level and the underside of the upper level. Have you thought about the visual separation? How will you avoid seeing wires and point motors above the underground station? (Wouldn't the underground platforms, all 6 of them now, be in three or more separate tunnels in reality?)

I think this is all very aspirational and imaginative but you need to get down to the practicalities. First things first: Build the shed - everything else is contingent on that.

Mightbe's design is simple and sensible but there are also two small issues with it, which I'm sure can be sorted out:

• The blue counterclockwise running line traverses a lot of points in the fiddle yard, so there's an increased chance of derailments and stalling problems. The red running line shows the ideal way to take multiple storage sidings off the running line.
• It's not possible to enter or leave the red storage sidings without running through the station.

I don't see the point of the lower level at all because you'll only ever see a tiny proportion of it, where the lines are near the edge of the baseboard and even then not fully. It's a massive amount of effort and complexity for very little reward and I would strongly recommend abandoning it.

If you want to model the underground as part of your terminus it might be better to have somewhere where the underground line momentarily opens up to the main level and implement a really simple loop through it on a demountable board so that an underground train appears every now and then.

On the terminus level: I think you're saying that the green tracks are non-scenic and therefore they simply have to work practically, not look realistic, right? If so, fair enough but even so, everything you can do to open out the radii will make the curves more friendly for long trains.

The station seems unbalanced to me: much too much platform vs. station throat and approach lines. Platform is very boring to look at. So I would reduce the number of platforms and reduce their length.

Maybe locate carriage sidings in the north west corner and locate loco stabling in the south west corner, outside the (increased) curve of the main running lines.

I would try to rationalise the fiddle yard so that the storage sidings are as straight as possible and all of similar length (maybe with parallel point ladders). I would reduce the reversing loop to a single track. And I think I would try to re-organise things so that the southern board is mostly non-scenic, devoted to the fiddle yard and other technical stuff.

Also, I suggest you think more about the environment around the station platforms - the background, the station concourse, station buildings, surrounding roads and buildings, etc...

Some domestic DIY grade LED tapes can be disappointing in their light levels and the (lack of) density of light sources.

Best to get architectural grade LED tapes, if it's not too late...

Three points about a circuit layout vs. fiddle-yard-to-fiddle-yard:

1. You can operate the circuit as if it were yard-to-yard. You don't have to perform continuous running but it gives you the flexibility to do so if and when required. (e.g. running in). And it gives you the flexibility to imagine that a train which ran through the station earlier and stopped in the yard, took some other route around the imaginary rail network to later re-appear in the scenic area from the same direction as last time.
2. If you set a train running continuously you can think of it in two ways:
   1. The train is travelling for a more realistic length of journey and on that journey the station represents other stations further along the line.
   2. The train repeatedly passing through the same station represents other traffic on the network.
3. A circuit usually has a more compact form factor that uses space more efficiently and is easier to house, easier to display, easier to sell on if that time ever comes.

Sorry but I can't answer about N-gauge reversing loop radii - not my area of knowledge.

Have you been looking at the sketch on my desk?

 

That is exactly what I had in mind Phil.

Great minds... :-)

Idea: You could conceal the LED strips above the trim timber so that they just cast their light down the sloping ceiling surface without being directly visible and that would also disguise any slight variations in the plasterboard alignment.

Something like this:

Hi (from one insomniac to another!),

Turnback loops (or reversing loops) are usually difficult to incorporate in my experience because they take up a lot of space but they are very useful on layouts with terminus stations. You will probably have to use track that crosses the room if you want one with a reasonable radius (even for unseen fiddle yard areas) and that would mean either some lifting sections in your baseboard or you have to be willing to duck under the boards somewhere to reach the central operating well. You only really need a single track to form a reversing loop. All this is entirely doable and it leads to possible bigger changes: If you have one track that crosses the room then why not run others, and have the main running lines form a circuit around the room (possibly below the terminus level)? That is a pattern that C J Freezer used many times.

I think that SCARM output just makes a design look like it uses settrack because it encourages you to plug together fixed geometry components. The SCARM file might be useful to some but not all of us. (Could you avoid the compression artefacts by outputting as PNG?)

Another layout that might give you inspiration is "Crewlisle". It's creator/operator is an active member here and he may be able to offer you some advice.

Hi,

Since the lifetime and ultimate position of this proposed layout is uncertain, and since you might be buying in baseboards, I suggest making this essentially portable - connected boards that could be broken down. That would allow you a lot of flexibility: Move it, store it, sell it, mount it above or below another layout, etc...

That would also facilitate my second suggestion which would be to make it a continuous circuit. Have one through fiddle yard behind the scenic through station with 180degree turns at each end (in simplistic terms). That would allow continuous running, which would suit non-stopping trains, and is a bit more relaxed and possibly more satisfying to operate than shuttling from one end to the other.

You could do that on boards of total size, say, 4000mm by 900mm maybe with some extra width at the ends to ease the curves.

Did Oxford (or your imaginary version of it) have sidings/yards in the 80s/90s?

I'm sorry, but you are wrong regarding gradients. Most RTR locomotives struggle on all but the gentlest of grades. Add curves into those grades and they'll simply slide to a hault. 10-12 coach trains would be impossible. In fact, I doubt most would even haul them on the flat with the radii being considered here.

I said "steepest workable for small trains"...

Railway Modeller magazine state that 1 in 36 is the steepest recommended gradient for OO layout designs submitted to them for publication.

I realise that there are lots of different opinions about gradients and what's workable very much depends on individual circumstances like rolling stock, train length and the radius of any curves.

BTW: I think James said that only shorter, underground trains were intended to ever traverse his proposed inclines - not 10-12 coach mainline traffic...

Hi James,

There's nothing wrong with ambition if you've got the time, money and drive to back it up - and 2500 by 7500 mm is a good space to do something impressive in!

But as you are finding, even a relatively large space requires compromise and clever design to accommodate a good model.

One of the arts of railway modelling, one of the "black arts" perhaps, is how to compress the real railway beyond simply scaling down prototype elements and yet still give a believable representation of the real thing. (Of course, if your main interest is operation then perhaps realistic appearance may be further down your priority list.)

For instance, where a terminus might have 10 platforms in the real world, maybe modelling 6 would convey a good sense of the prototype and 6 coach mainline trains may look entirely believable in a model.

138mm between levels should be fine for OO - the minimum is generally thought to be 100mm (depending on your baseboard construction method). 1 in 36 is usually reckoned to be the steepest workable incline for OO - and that only for small trains.

See if you can find a copy of C J Freezer's "Plans for larger layouts". It should be inspirational but be wary of his stated minimum radii - they are often tighter than perhaps we would be comfortable with these days.