Coblars Wick II

[Ray H]

Attempt No. 1 after returning to the hobby following a 35 year break was a BLT with headshunt, two road goods yard, run round loop, main and bay platforms and a kick back siding in front of the fiddle yard. The fiddle yard itself was cassettes and I found them cumbersome and were the main reason (besdie the lack of operational interest) why I started again. Scenery got as far as a platform and a couple of Metcalfe kits.

 

Attempt No. 2, which is currently still in existence and sports a tad more scenery but not a lot, is based quite loosely on a compressed version of Bodmin General. The platform can just accommodate two coaches (for running round) and the fiddle yard is an eight track traverser, much better than the cassettes. However, the trackwork was largely recovered from the first layout where it had been glued down and I think it became slightly distorted when it was lifted. In addition, as I've only recently discovered following other investigations into poor running, that I've managed to introduce dips in the rail ends at most baseboard joins that can probably only be remedied by relaying the affected sections of track.

 

There was plenty of operation interest but as I developed the scenic side - not my forté - I found it difficult in the baseboard depth available to emphasise the fact that the two tracks leaving the station were in fact meant to be two different branches. The need to relay several lengths to resolve the track defects led me to think of other ways to improve both the operation and scenic side. It didn't take long to justify starting yet again. As I am probably best advised to replace the pointwork, I might as well look at building my own - copper clad in the fiddle yard, chaired track on the scenic section.

 

Soon after resuming modelling I'd join a club and have been involved in working on their layout which has a continuous run. I recognise that this is ideal for testing locos and stock and lets one sit and watch trains go by if you don't want to operate too realistically. As a result I began to wonder if I could incorporate a continuous run in my revised layout. After a fair bit of head scratching I have arrived at the plan below which I hope is reasonably self explanatory.

 

Unfortunately I have had no option but to resort to 18" curves to accommodate the layout in the (likely to be) available space. I originally planned to have all these curves on the hidden section. However, I soon realised that in doing so the visible section of the layout was less then 25% of the overall footprint so the scenic side looks set to expand.

 

The station platform tracks, goods yard and all pointwork on the scenic side will be on a raised level, about 2" above the baseboard top. The two (18") curves will be on gradients, probably about 1 in 30 and the fiddle yard will be on the baseboard top. The branch line will climb up from the platform, enough to clear the running lines below - the branch alignment is still subject to review.

 

I should, at this point, indicate that nothing is set in stone and because I will need to pincheven more room space to accommodate all that I want to incorporate, I may yet have to forget any idea of having a continuous run so please bear with me if all this comes to nothing.

 

And so to the first question. Should I consider putting a slight camber on the outside of the 18" curves - perhaps as much as 1mm? If so, could I achieve this using a strip of card under the outside edge of the sleepers or would the void under the sleepers between card edge and where the track touches the baseboard cause more problems?

 

The second question relates to DCC operation. I opted for DCC when I started buying stock and controllers (no longer having any of my previous models). I've already upgraded from a Dynamis to and NCE PowerCab. I don't plan to have sound and the scope for shunting is limited (and has been on the previous two layout attempts). There are a few features that I'd like to incorporate into the new layout that I believe would be easier in DC rather than in DCC where it appears each loco has to be specifically assigned to individual controllers.

 

Realistic operation suggests that trains (in oposite directions) are liable to depart from the station at about the same time (rather than waiting for the first departure to arrive in the fiddle yard before the second train can leave the station). It would also be useful to be able to incorporate an automatic station (or signal) stop which I believe is beyond DCC. As a DCC novice (still) I'm beginning to think that if this layout design goes ahead I'd be better having it DC (cab control) operation? Does this seem right?

[Ray H]

Apologies for the second post but I don't seem able to edit i.e. update the layout plan in the first.

 

The branch now ends in a sector plate and all three baseboards are approx 3' 5" long (to fit the room length available).

 

Out of interest I've tried to edit this post and can.

[Kenton]

IMO, and possibly only my opinion, the amount of space taken by hidden area (FY) is much to large and complicated compared to scenic, though plan 2 is an improvement.

 

I think I have missed the mention of what scale you are in though am guessing it must be 2mm/N gauge? with you operating from the back (FY) side. That makes the inevitable stalling loco/derailment/uncoupling episode out of reach and requiring a walk round to the front. Especially true if there is a backscene in the way as well.

 

Finally gradients are generally much harder to implement on curves than on straight runs. Not impossible, just difficult, and made worse when you have gradients steeper than 1:50. I don't think you will get enough space to clear the sector plate - in fact I am certain you will not.

 

Oh, and I would opt for a traverser every time. Point ladders always require more space.

[Ray H]

Many thanks for the comments, I know everything is a squeeze.

 

The layout is 4mm/OO, hence the 18" radius curves - the room available is only just over 10ft in length and I'm pushing things to get the main part of the layout into 2' 3" depth, the idea being that the loop tracks will be on lightweight boards/wings that fold up when not in use.

 

Sorry the baseboards were badly drawn. The slim ones on the fiddle yard side won't be rectangular and there'll only be two of them, probably more like 4' 9" long close to the point ladders. The point ladders are only there because I can't get a traverser in if I want to run three coach trains.

 

I've updated the layout plan to show the baseboard arrangement clearer.

[Kenton]

4mm/OO well that is even less likely to succeed in gradient terms. Oddly my experience of 2mm/N locos is that they broadly seem to be able to negotiate inclines with a little more ease. Some of the OO locos are seriously underpowered.

 

But this is not about just getting the loco to pull a single skinned rice pudding van up the incline it is all about the gradient possible. I still cannot see the requirement for the sector plate as all it does is require the rest of the layout to have a gradient to get up over or under it. Without the SP the whole of the rest could be single level. The SP is also going to be some 2-3ft reach away over other FY tracks - difficult. Take the section of track from in front of the signal box to where it passes under/over the SP, ignoring the fact that all gradient must have transition element to work (ie you cannot go from flat immediately into maximum gradient) you have slightly less distance than a board width (3ft) in which to make full clearance height for the SP (remember clearance will not only be the height of the tallest loco as it will also need to include the base board layer and track depth of the upper level.

 

I still think it would benefit from a traverser rather than the two opposing ladders. A traverser will always give more train length than a point ladder.

[Ray H]

I added the sector plate having re-located the hidden part of the "branch" when I only latterly realised the original tracks could not be reached from the control point by the ladder. As the track move would then require a kick back point (which I would have preferred) the branch fiddle yard track (i.e. where the sector plate is) would have been only a little over a foot in length. I believe that I can just fit a pair of 50' coaches and a small tank on the sector plate, something I couldn't do if there was a point.

 

I was going to investigate motorising the sector plate's movement.

 

Believe me, I tried fitting the traverser in as I follow your argument for having one. It would fit if I reduced the maximum train length or had it nearer to the back of the layout. It also had the potential to provide an increase in the storage capacity as I could add some parallel siding linked solely to the traverser. However, as I need to be able to condense the depth of the layout when not in use, the present plan keeps all the stock on the layout whereas some of the stock would probably need to be removed if a traverser was in use and the traverser would need to be able to be left on the main part of the layout which may infringe on the scenic part of the layout.

 

The intention for the gradients was partly to take away the flatness that many models tend to exhibit as well as providing a means to accommodate the original branch fiddle yard. I hadn't noticed that the gradients would now need to be a lot steeper with that fiddle yard moved.

 

As I see the branch taking an active role in the operation interest of the layout - I almost have the day's timetable worked out - it does look as though I need to go back to the drawing board or compromise on train lengths. That said, I suppose I could look at having shorter trains that stop in the station loops and longer ones that don't. That would allow for shorter platforms and potentially enable me to increase the length of the branch fiddle yard with everything on one level.

 

Thanks for the ongoing comments. I'll happily take more. I've spent several weeks on this idea, gradually refining the design to remove obstacles that I saw. Usually I come up with an layout idea and the track layng starts almost immediately (and the layouts then last correspondingly little time!).

 

I really hate the idea of 18" curves but I can't see a way out of that if I want a continuous run.

[Kenton]

A suggestion: on the left FY, why not make it specifically for the branch and its loop back (introduced in plan 2&3. The SP could be angled more like in plan 1 and even made 2-4 tracks in size and longer than it is now. Of course this would sacrifice the point ladder on the left.

 

By moving the FY exit point backwards on to the LH flap and remembering that FY does not have to be all straight track the RH could be increased in size even still using a point ladder. BTW ladders going off as a fan in both directions ie incorporating a 3 way as the 1st point in the fan are longer and therefore hold more stock. Of course the really bad down side to this solution will be the required reversing manouvre to get in and out of the FY from the wrong direction (RH side).

 

Small scenic gradients are a nice to have but were relatively rare on the prototype in as much as you would notice. They can really complicate a model railway for example how do you cope with uncoupled wagons/coaches to stop them rolling out of position? (Yes I know modifications can be made to mimic brakes, but over complicating things IMO). There is a difference between scenic features removing the flatness and a changing level trackbed. Oh and remember you can always create height by going under the track a culvert for example. Also do not forget that where the scenic section plunges through the backscene into the FY requires some thought. Tunnel entrances are not always convincing at either end of a station without the evidence of the ground levels to support them.

 

Anyway, too much of me and my comments - need others to join in to contradict me.

[Ray H]

I've bitten the bullet for the ime being and taken more depth for the main boards, thus icreasing the footprint when not in use (which I still have to negotiate) as this is the only way that I can squeeze a traverser in.

 

The two track traverser allows me to run trains onto the traverser from opposite directions, possibly simultaneously (although I've yet to establish how I can do this with just one DCC controller unless I have a switchable dead section to stop the trains) - I'll probably add a buffer stop or at least a couple of short loco spurs to the left of the traverser.

 

I've had to reduce the length of the branch fiddle yard in order to shoe horn it in behind the backscene - there's a chance that the backscene position shown may be that at baseboard level. I may then have a raised scenic area over one or two of the fiddle yard tracks otherwise the layout will be all track and very little scenery.

 

Although I've shown a single track sector plate for the branch I suppose I could try a second 2/3 track traverser or 2/3 tracks on the sector plate without linking either to the (main) traverser.

 

I did have one other thought. Instead of having a single track passing loop I did wonder whether one curve could be double track and the other single track - possibly the right hand curve as the double - the long siding at the froont of the layout is to be used to recess frieght trains from time to time as well as using it to store odd wagons or the stock off the branch passenger if I need to get it out of the way to allow other trains to pass in both directions (although I presume that it would be legitimate for the branch passenger to shunt back onto the branch to allow other trains to pass).

 

I'd welcome any further comments on the revised design and also on my original queries regarding using a camber on the curves and whether or not sticking with DCC will impose more restrictions in the operation of the layout compared to DC.

[Ramblin Rich]

One thought to increase the length available on the branch sector plate - could you arrange a slight height difference (<1cm) between main & branch (perhaps a downgrade on the main)? This might allow you to add a "drawbridge" style flap arrangement at the end of the sector plate, dropping down over the main when you need to accommodate a longer train?

[Kenton]

One thought to increase the length available on the branch sector plate - could you arrange a slight height difference (<1cm)  between main & branch (perhaps a downgrade on the main)? This might allow you to add a "drawbridge" style flap arrangement at the end of the sector plate, dropping down over the main when you need to accommodate a longer train?

 

This would go back to the original design. If the SP has to clear the main line then you need a lot more than 1cm height change.

 

I have to say that I was thinking of a multi-road traverser in the middle (perhaps not made clear enough), all those storage roads now block the return loop to the SP.

[Ray H]

I puzzled for a bit over Rich's suggestion but then realised that he was effectively talking about a short term extension to the sector plate to allow the (longer) branch train to run onto it. Then, as soon as the sector plate has been move to link up to the other track shown and the branch train has left the sector plate, the extension could be lifted. The curve under the extension would be blocked whilst this is happening but that wouldn't necessarily be a problem.

 

I would point out that the idea is that the traverser has two roads as this will allow trains to approach from either end simultaneously. Both traverser roads can then be linked to any of the tracks inside the right hand side curve, and the branch also links to the traverser on the left hand side.

 

I'm not too worried about the reduced length of the branch trains ( so won't need the extension) as long as I can run the occasional three coaches and a tender engine on the main.

 

The latest drawing which I had intended to post earlier shows a variation on the sector plate idea. It's still a shortened length sector plate but is now self conatined with three tracks which should be enough for the branch. I could also, but haven't shown it, have a few curved sidings to the left of the traverser to provide extra storage space.

[Friar Tuck]

There seems to be no hidden siding for trains heading anti-clockwise out of the station on the main line. Where will they go, except back into the station again?

[Ray H]

Trains leaving the station in either direction will run onto the two track traverser - clockwise normally onto the lower of the two tracks in the plan, anti-clockwise onto the upper of the two tracks. This will be the normal method of working. However, if I want to tail chase I can do so by using the point to the left of the traverser (in the plan) and set it so that trains can use the upper traverser track in either direction.

 

I hope that makes sense.

[Ramblin Rich]

I puzzled for a bit over Rich's suggestion but then realised that he was effectively talking about a short term extension to the sector plate to allow the (longer) branch train to run onto it. Then, as soon as the sector plate has been move to link up to the other track shown and the branch train has left the sector plate, the extension could be lifted. The curve under the extension would be blocked whilst this is happening but that wouldn't necessarily be a problem.

 

I would point out that the idea is that the traverser has two roads as this will allow trains to approach from either end simultaneously. Both traverser roads can then be linked to any of the tracks inside the right hand side curve, and the branch also links to the traverser on the left hand side.

 

I'm not too worried about the reduced length of the branch trains ( so won't need the extension) as long as I can run the occasional three coaches and a tender engine on the main.

 

The latest drawing which I had intended to post earlier shows a variation on the sector plate idea. It's still a shortened length sector plate but is now self conatined with three tracks which should be enough for the branch. I could also, but haven't shown it, have a few curved sidings to the left of the traverser to provide extra storage space.

 

Yes, sorry I should have made myself clearer about the temporary drawbridge only being needed when the SP was in use - but if you're just using shorter trains, no need to over complicate!