davidwoodcock wrote:To me, this seems to be the point where your "history" moves from the unlikely but not impossible of the rest of your scheme to unbelievable.
davidwoodcock wrote:What might, though, have been possible is an extension of the ~2ft gauge lines of the quarry owners to an MR terminus at Nantlle. (In reality, their slate output was trans-shipped twice 2ft to 3ft 6in and 3ft 6in to 4ft 8½in.)
kbarber wrote:I notice you call it Nantlle (MR) but your blurb refers to it as 'Caernarvonshire Railway... assumed by the LNWR...' so I wonder if you're actually intending a LNWR influence here (with, presumably, running powers from Bangor to PLJ)?
kbarber wrote:The LNWR was rather a parsimonious outfit when it came to signalling branch lines. I wonder if (to add yet another variation of signalling practice) Nantlle might have been signalled with ground frames with Annetts key releases between them.
kbarber wrote:I don't know what the rationale is for two crossovers (7 and 9), unless there was a very good reason involving lots of extra revenue I'd expect even the most lavish company to try and provide only one of the two.
kbarber wrote:If it is MR, although there probably would have been a signalbox of sorts I'd still expect as few signals as possible (certainly no shunt signals) and, likewise, unless there's an exceptional justification for the expenditure, only one of 7 or 9 crossovers. Again it's a moot point, regardless of the kind of building provided, whether the apparatus would be considered a signalbox or a ground frame - in the latter case the operator would, again, be the shunter or guard and would be assumed to be in direct control of all movements in any case. Even if there was a signalman properly so called, the MR wasn't one to provide shunt signals - the signalman was expected to control movements by handsignal.
Mike Hodgson wrote:Are you expecting to have a freight come in and spend a couple of hours shunting using the train engine, whilst passenger services come and go? This is much more plausible economically (although it still assumes a more intensive passenger service than seems likely in rural Wales), but locking using only Annetts keys on the train staff would again be very limiting. Many branches were worked like that without needing full signalling, but it was typically a freight train using a two or three hour window in a sparse passenger timetable, and that meant it could carry the train staff.
Mike Hodgson wrote:Much as I like co-actors, I don't see the case for one here (15) although the LNWR were unduly fond of tall posts. Since any departing train is starting from rest, you don't need to see it from afar, so surely all you need is a short post to provide visibility under the bridge.
Mike Hodgson wrote:I don't know what LNW practice was with running shunts, but 3/4/5 signals seem a long way past the Home signal. I'd be happier with a running signal there, but if you follow KBarber's advice and dispense with 7 crossover, I think you should be moving 1 signal to that spot anyway.
Mike Hodgson wrote:My problem is more to do with the general geography of the station than its signalling, and of course any changes you may make to the station layout will impact the signalling. The goods shed location looks fairly improbable.
Is it (as I would expect given this layout) from a road leading to or past the platform end at the extreme right, or is it off the road overbridge in the middle?
Mike Hodgson wrote:12 crossover seems a long way down the platform, making the main part of the platform difficult to use. And if the main station building is indeed at the right hand end, you don't really want all the passengers to have to walk all the way to the far end of the platform to board their train. So will the train be pushed back towards the stops after running around? Or will they have to walk to the narrow part of the platform clear of 12 crossover? I think I would probably want a bolt lock on this crossover, which I would expect to be controlled from the ground, using only hand signals.
Mike Hodgson wrote:You don't show the cattle or end-loading facilities which would be usual, though I suppose you might be able to cater for end-loading by going though the goods shed.
Mike Hodgson wrote:Do you really need those gates on the exchange siding? That implies some sort of fence - so where exactly does that run? Does it not impede cart access to your goods shed (over the tramway track)?
Mike Hodgson wrote: For loco-hauled departures, they will have to be reset after the run-around. For auto-coach they could run coach first into Nantlle. I assume you are saying that the signals 19 and 6 are not needed? But that the box would have a bolt on the 12 crossover to ensure it is open before the signals into the platform can be cleared (and presumably that would double as the GF release)?
kbarber wrote:Adam, I wonder if you're assuming the goods would precede the passenger up the valley and need to shunt while it was running up from PLJ and back again, then depart for PLJ as soon as the section clears? That would need the kind of signalling and facilities you're talking about. But what seems more likely to me is that the goods would follow the passenger up, get inside to allow the passenger to depart and make whatever shunts were necessary that side while the passenger was still in section.
kbarber wrote:That would be even more apparent at the end of a small local branch than on a busy main line (though even there you shouldn't expect the sort of gratuitous provision a modeller would love to be able to get his teeth in to - everything would have a purpose and its benefit carefully costed).
tynewydd wrote:Agreed, but we have to look at the factors that allow economy and what resulted, and actually, I have another prototype branch terminus to look at that fits the model slightly better is several respects - Bethesda. Bethesda was on a steep line rising 300 ft (forgot to mention that for modeling purpose we have a steep gradient up). It was a slate transfer point in competition with a narrow gauge railway for slate traffic to the sea (Penhryn Quarry Railway). The trip time to Bangor was 18 minutes and, one imagines maybe longer uphill. In 1932 it had 16 arrivals and departures daily and 19 on Saturdays. Admittedly after the war the service level was so kept low at 8 per day that it lost out to bus traffic and had no passengers beyond 1951. But it did have a run-around loop within the platform length (but was mainly push-pull) and crucially a signalbox which didn't close until 1954. It had a layout with a constrained footprint, with a station building accessed from a station road orthogonally across the end. Didn't have NG interchange sidings, but had extra length of goods sidings that were used to load slate from carts and a goods shed for freight from a local lorry service, cattle dock, etc. I don't see a box diagram around for Bethesda, perhaps someone has one so we can see what it controlled?
I hope we can agree to some modeling license in that the combination of less parsimonious service with the difference between a stopping bus time to Caernavon and Bangor and high-speed train time via PLJ - especially in tourist season - would have resulted in continued passenger service for at least another decade.
I am not wedded to all of the signals - bracket 3,4,5 looks like overkill to me, now, for example. I am wondering about that middle bridge, it does tend to break up the scene which is good, but it reduces the operability of the layout and introduces some possibly un-needed partitioning in the yard(s).
I am wedded to the signalbox - removing that means depriving someone small but feisty of "her" box and "her" bells. Just as in the real railway there are sometimes factors beyond pure economy that drive decisions!
But I do appreciate the input as always. It certainly drives my thinking in the right direction.
MRFS wrote:Can't find my Wagstaff diagram, but there is an SB on the 1889 OS at Bethesda - far end at the station throat.
davidwoodcock wrote:MRFS wrote:Can't find my Wagstaff diagram, but there is an SB on the 1889 OS at Bethesda - far end at the station throat.
I think that is probably the GF for working the goods yard points and released in typical LNWR fashion by Annett's Key. Bethesda was long and thin and a box at the station throat would have been too far out, certainly in 1889 and probably later, to have worked the points for the platform loop.
By having an open GF on the platform the LNWR saved the cost of a dedicated signalman - as they did at almost every branch terminal in North Wales. I may have missed one but I suspect that only Llandudno, Blaenau Festiniog and Afonwen had proper boxes and they were all special cases.
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