Harlequin

It does look very interesting - there's lots going on and a number of different levels. (On the maps you can see that the LMS and GWR lines ran parallel at this point and there is a GWR wharf just bit further North.) The question is, how to compress and distil this down to your small layout footprint? It would be great to make the most of the L shape and I'd suggest making both arms scenic rather than consuming one with a fiddle yard, if possible. So looking at Chillington Wharf, one arm could be transfer shed, basin and a small array of sidings and the route out could curve round, under the LMS main line as a scene divider to a set of exchange sidings, which act as the fiddle yard on the other arm. (You could pose mainline locos on the over bridge even though you haven't got room to run them.)

Wow! That's fast work!

I was thinking of something like the note at the top of Modelling, Musings & Miscellany: "Before you post in this area..."

I think I can see what you're talking about. I won't spoil the fun for others. The beauty of this composition is not only in the two locos but the foreground detail and the background buildings! Lovely stuff!

My understanding of the layout topics area is that it's for people to write about existing layouts, right? A bit like a collection of blogs but more open and more interactive . But it's quite common for people to start new threads in that area to ask specific questions about layouts, designs or technical issues, so I wonder if it might be possible to add some guidance to help people post questions in a better place? Just a thought, not a big issue!

Hi Bolt, Fiddle yards under scenery are usually a bad idea but your traverser should be OK, as long you use fully extending draw runners so that you can pull it out to get at all the roads. I think the turntable under the scenery would be a nightmare though. You could use loco-lifts to turn locos on the traverser instead. Train access to the FY is also a bit of a problem because they always have to leave the main layout from the inner circuit and to gain access to the outer circuit they have to run in the wrong direction on the inner circuit for a short distance. Furthermore, there's no way to turn a loco on the scenic level so, unless you use the hand-of-god, tender locos will end up either reversing their trains back down to the FY or running round and hauling them down tender first - neither ideal. And there are a number of other problems with this arrangement. Roundy-round designs benefit from have a through-fiddle-yard where trains can arrive from either direction, the loco can be turned and then the train can later leave in the opposite direction (on the other line). The space you've got available is on the smallish side but reasonable and so to fit everything in I think you need to use the volume as efficiently as possible. Good decision to abandon the narrow gauge layout for now - it might be possible to thread some narrow gauge into the main layout design once you've got it sorted. P.S. This topic should really be in the "Layout and Track Design" section.

You can buy whole sets of “replacement key caps” (enter that phrase in your favourite search engine). For longevity the feature to look for is “double shot”. This means that the key caps are moulded with a void in the shape of the letter and that void is then injected with a different coloured plastic - so the letter will last a long time and only wear out when the entire cap wears out. Edit: Check that the new caps attach in the same way as your current ones. It has to be said though, that you can buy a whole new keyboard for the same price as a set of key caps...

Hi David, (That post was at 10.20 BST.) The problem is that if you just do simple frog switching and you accidentally set both points to turn then one of the frogs will be the wrong polarity and when your loco hits it you will get a dead short. So you might say, that's OK, I'll just remember not to set both points to turn (which is what I was sort of saying above) but the issue there is that you will either forget, or you'll become paranoid about checking it, or someone else using the layout won't know about it. Just general annoyance. That's why an interlock really is the best solution. Edit: With wire-in-tube, you could probably arrange a physical interlock that allows either point to be set straight but if either is set to turn it pushes the other straight at the same time... Sounds like a fun mechanism to set up!

"Grand Model Railway Designs" Each week the team descend on a member of the public, create a space in his or her house and within it install the model railway of the subject's dreams. With a very tight deadline, of course. Do you think Kevin McCloud and James May would get along as presenters? Who would be good as the obligatory third presenter? Needs a celebrity electronics wizard with a difficult personality, I think...

Hi John, The photos are wonderful and aspirational for a lot of us! Thanks for taking the trouble to upload them. I too have occasional problems uploading images (long delay followed by error 201 or 200) - seemingly always just when I'm trying to post something in a hurry. Very frustrating. I have tried various technical incantations to try to unblock things. Sometimes they seem to work, sometimes not so I really don't know where the problem lies but if you are experiencing something similar it's a bit less likely the problem is at the client end of the connection. P.S. How about red lamps on your grubby old workhorse 28XX?

Yes, Izzy and Grovenor are right - interlocking is the only sensible way to tackle this problem. In Penlan's specific case, where he is using Fulgurex point motors, I guess the basic idea would be to use one auxiliary switch to feed track power to the opposing crossing V and use another to control the power supply to the other motor so that if one point is set to turn the other one cannot be. It would be possible to do something similar using DPDT switches and solenoid point motors.

On tonight's episode of Grand Designs - The Street, Kevin McCloud said that if he had the chance he would devote an entire floor of a new build to a OO model railway, adding "They're brilliant!". Wow! That's a whole new genre of crossover TV that I would love to see!

It would be nice if that were true and you got me thinking hard there but I don't think that stacks up because of the interlacing. The interlacing means that for either of the turning routes, both Vs are traversed but only one set of point blades is traversed. Thus, one of the Vs can be set to either polarity without changing the route and can thus be the wrong polarity for the route. You do have a point, though, (sic) that my solution might be electrically the same as two simple SPST switches when analysed. If that's the case then, urgh, sorry everyone!

Yes, as previously stated, if both points are set for the curve then it's impossible to give the crossing Vs any kind of correct polarity because both Vs are on both routes through the slip. But there's no point setting both turning routes at the same time and so, as long as one or other point is set straight, that wiring will do the job and the familiar DPDT switches can be mechanically connected to the point operating mechanisms in various familiar ways.

Edit: Rubbish idea removed.

Hi Izzy, Yes, I see what you mean... My excuse is that it was late when I was trying to work it out! I think I can salvage the idea by changing the connections from the Vs to the switches. I'll post a revised version when I get time.

Yes, sorry Chris, none of my gripes refer to your plans, which are very nicely drawn. So it's all bit off topic!

Yes, sorry. I felt the need to have a little dig because my heart sinks every time another grey, jaggy, axis-aligned design is posted on RMWeb. The full on package is expensive, true, but there are more cost-effective versions in the range that would do the job. Unfortunately my bosses have different priorities these days.

With traditional track planning software, yes... That would the same software that lines track up parallel to the baseboard and outputs dull grey images with horribly pixelated edges...

That's right. Either ground frame and no disc or no ground frame and disc.

Here's a photo of the loco release crossover at Moretonhampstead: If the crossover was operated by a ground frame I think it would have been roughly where the ground disc is or where the crossing boards are - between the tracks. The ground disc probably has simple detection to ensure it can only be pulled off when the adjacent point has been set properly. Notice the signal cable for the disc running parallel with the point rodding all the way back to the 'box.

Yep, I agree. I think that each of the crossovers would be operated by a single lever in the box (whether operating the points or just releasing a ground frame) - for the crossover near the box that might still be two rods leaving the box though - it depends where the action is split. BTW: Is the extra rodding run to the right-most point for the Facing Point Lock that would be required at that position? If so, Bonus Points!

Could the navigation menu(s) be "sticky" (technical term) so that when we are scrolled down a long page (of which there are many on RMWeb!) the navigation controls are still to hand? I realise that the grey "back to top" arrow shows the navigation controls again when they are scrolled off the top but it would just be bit neater and more direct if the navigation controls didn't disappear in the first place. I imagine that while the scroll position was at the top of the page you'd see the full fat menus as currently but when scrolled down they would transition into a slimmer version to take up less screen space. Edit: This would have the advantage for the site admins of keeping the RMWeb branding on screen at all times...

I think Jim's correct: There's a combination that always results in a short. When the two points are set to take the two turning routes at the same time then each V is on both routes and so each needs to have both polarities. (Boom!) So you have to either prevent the two turning routes from being set simultaneously or allow it and in that case make one or other (or both) of the V's be dead. Edit: Rubbish idea removed.