Hello everyone,
I am trying to devise a plan for a possible layout. I would be grateful if those 'in the know' might offer some insight into standard gauge curve radii and what size of loco might be able to traverse such curves. I have been looking at Google Earth and using the tape measure and have found that e.g. the north to east curve at the start of the Castleton Branch immediately south of Bury Bolton Street station on The East Lancashire Railway has a main radius of about 200m. As far as I am aware 9Fs can negotiate this curve. Obviously it is a low speed curve although I don't know what the speed limit is and, unfortunately, the ELR website seems to be unreachable at the moment otherwise I'd ask them.
If anyone has any handy advice I would be most grateful.
Thanking in anticipation.
Chris.
On the modern railway 200m radius is not unusual - it's the minimum allowed without a check rail. Radii on running lines probably go down to about 150m, with less in depots and sidings.
Be aware that most curves on models are hugely underscale compared with the prototype, and would only allow very slow running if they were possible at all. For example a 1000m radius curve - nearly 7 metres in N - will have a maximum speed of between 70mph and 95mph depending on the cant (superelevation).
Quote from: edwin_m on September 21, 2019, 05:25:58 PM
On the modern railway 200m radius is not unusual - it's the minimum allowed without a check rail. Radii on running lines probably go down to about 150m, with less in depots and sidings.
Be aware that most curves on models are hugely underscale compared with the prototype, and would only allow very slow running if they were possible at all. For example a 1000m radius curve - nearly 7 metres in N - will have a maximum speed of between 70mph and 95mph depending on the cant (superelevation).
Thank you edwin_m. That is very useful. Do you, by any chance, know what a realistic speed limit on a 200m (ish) radius curve might be?
I'd say 200m would be unusual. Morpeth is 340m, and that has a 50mph limit. I'd expect a 200m curve to be off the main running line and 20mph or below.
Quote from: njee20 on September 21, 2019, 07:14:19 PM
I'd say 200m would be unusual. Morpeth is 340m, and that has a 50mph limit. I'd expect a 200m curve to be off the main running line and 20mph or below.
Thank you njee20. That is REALLY encouraging. I believe the speed limit on our heritage railways is 25mph (except the GCR) so your notion of 20mph is pretty much what I was hoping for. Mine is not intended to be either a main line or a high speed line. The essence of it is is a private railway built in an abandoned quarry in deepest, darkest Cornwall where the owners run their utterly Rule 1 stock. It is not connected to any other railway but I wanted to place it somewhere real in order to give it a sense of place where the actual location will guide the scenery etc. :thumbsup:
If you're really wanting prototype fidelity it's the pointwork that'll let you down, even Peco large points are very tight in real terms.
there is a photo of the castleton curve on :
https://en.wikipedia.org/wiki/Castleton_railway_station
Quote from: njee20 on September 21, 2019, 07:27:38 PM
If you're really wanting prototype fidelity it's the pointwork that'll let you down, even Peco large points are very tight in real terms.
You are absolutely right. However, I am creating a 'fictitious prototype' on which I then base my model. TBH a circle of prototype SG track at 200m radius would require something like a baseboard with a 8 foot square footprint which is way too huge. My layout will be much compressed to 7' x ~2' 6" for the main circuit. This will be plenty it's just I wanted the 'prototype' to be feasible if you get my meaning. Thanks for all your help.
With N gauge it's sometimes possible to hide the tight curves out of view and have realistic curve radii in the scenic area.
Quote from: chrispearce on September 21, 2019, 06:38:21 PM
Thank you edwin_m. That is very useful. Do you, by any chance, know what a realistic speed limit on a 200m (ish) radius curve might be?
I reckon 30mph with no cant. If there is some cant it would be higher, but it's sometimes difficult to get enough cant on a tight curve (you need a real track engineer for that!).
Quote from: edwin_m on September 21, 2019, 08:59:54 PM
Quote from: chrispearce on September 21, 2019, 06:38:21 PM
Thank you edwin_m. That is very useful. Do you, by any chance, know what a realistic speed limit on a 200m (ish) radius curve might be?
I reckon 30mph with no cant. If there is some cant it would be higher, but it's sometimes difficult to get enough cant on a tight curve (you need a real track engineer for that!).
Thanks again. That gladdens my heart!!!! I am actually considering superelevation where practical although I will have to work that one out when the build begins............ :thumbsup:
Quote from: edwin_m on September 21, 2019, 08:57:16 PM
With N gauge it's sometimes possible to hide the tight curves out of view and have realistic curve radii in the scenic area.
The curves which form the back quarter turns may be as tight as 2nd radius as this will cut down the width of the layout and allow for larger transitional curves at the front which is a preferred arrangement for me. The effect of trains going form tight curves to straight (ish) track always looked wrong to me even as a youngster but at the rear of a layout I think they are fine.
morpeth has steep curves, battersea pier junction london, i mean can you head to a station and see how the curves are lying as so to pseak in your local area chris to get a feel for it as so to speak to take a couple of shots ?
Quote from: crewearpley40 on September 21, 2019, 09:14:41 PM
morpeth has steep curves, battersea pier junction london, i mean can you head to a station and see how the curves are lying as so to pseak in your local area chris to get a feel for it as so to speak to take a couple of shots ?
The tightest curve here in Reading is 500m radius. It is the west to south chord of the triangle to the west of Reading station giving access to the Basingstoke/Theale line. I am happy with the 200m curve idea for my layout plan. If I can assume a 25mph speed limit that is normal for a heritage line overall and will be perfect. Right now I am pondering the best design for the layout support legs! Payday is on Thursday so I could make a start then. Some shelves and a framework for a side for my bath need to be done first. Oh dear. Domestic chores. The bane of all budding railway modellers! :veryangry: