Figure of eight

G

Glengrant

Registered
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OK chaps, here's the problem, and sorry if this blueprint isn't very professional, but as I keep telling you, I'm an ops man, let the technicians do the nasty work. Here we have the fairly classic dogsbone in blue, any idiot can do that (and I'm any idiot), and it all more or less works under the control of TM1. Inside the oval is a separate operation in green, and this should be controlled by TM2. It isn't, but I think there is a finger stuck in there somewhow, but we'll worry about that later. The idea was that this green line would be a simple out and back operation, although as you can see it makes an end on jucntion with the blue section. Possibility of blue sparks there if things aren't properly selected, I suppose. Now a new kid is about to arrive on the block, should be in the post soon, this being a crossover which will be inserted into the blue hatched line. This is not yet in postition. So what was a simple little oval with trains going round and round now becomes the dreaded figure of eight.
What happens next? Because I dunno. Should I take up aeromodelling instead?
 
I've just sat back and looked at this rubbish. Of course, there is only a problem for trains running anti-clockwise. Clockwise there's no problem, except that in that case there's no need for this new line. Oh, you'd already spotted that?
 
As far as I can see you do not have a figure 8, you have a return loop. That's where the sparks will come from.
 
Yes Mike, after I'd spent half an hour doing all of this, I then sat back and looked at it, and said, what the heck is this all about. A train can change direction once, and that's it. Oh well, the best known plans aft gang aglay and Soapy Solmon might say. What I have to do is either sell off all my existing stock and go over to a complete dmu or push-pull operation. Ah, then my little ATSF 0-4-0 with the slopeback tender will be useful. OK back to the drawing board
 
@glengrant - at the risk of a BFO, can I suggest approaching the problem the other way up? What do you want out of the layout? For example: showcasing rolling stock, in which case one or more ovals for a continuous run might be the thing, with a dumbell as an elegant but electrically more complex variant; varied operations, in which case, a figure of 8 with the centre of ops at the intersection of the circles with as much as possible there by way of passing loops etc to allow for remarshalling of trains, change of traction, but electrically simple; something more prototypical, which probably implies an end to end run - more tiresome to manage if there's only one man operation.

GH
 
your dotted line connects (shorts) plus and minus of the blue line.
i see at first sight two options:
1. isolate it at both ends near the turnouts, and give it its own TM.
means, when you let a train enter that line from any side, the diagonal-TM has to be set, that the train goes on.
while the train is in the diagonal, you would have to reverse the blue line TM.

2. you build in return loop electronic (just some diodes, that take any polarity and give out always the same polarity)
but you could use your diagonal in one direction only, and you would have to reverse the blue line TM anyhow.
 
http://www.youtube.com/watch?v=DPy3LXzhZTo < Link To http://www.youtube.com/wa...9E&feature=related

No, stay away from RC aircraft, if you derail your train, you just put it back on the track, if you derail your plane, you kiss it goodbye and start over again. One guy once told me regarding RC: If you can'y afford to wreck them, you in the wrong hobby.
 
If you're running on analogue then personally - unless it's vital - I would take out the reversing loop. I had one of these on the old Bredebahn and even with the LGB reversing loop modules it caused trouble (so it went!). Divide your track into power sections and allow plenty of spare room at the end of each section for overlap. To reverse a train, then do what they usually do in the prototype - take of the loco and use the run-round loop that you already have.
The other problem that you have to allow for are those coaches and locos that have wheels wired for pickup a distance apart - a long coach fitted with lights for example. They can easily bridge isolating joints, so must be drawn totally clear during operation.
 
vsmith said:
http://www.youtube.com/watch?v=DPy3LXzhZTo < Link To http://www.youtube.com/wa...9E&feature=related

No, stay away from RC aircraft, if you derail your train, you just put it back on the track, if you derail your plane, you kiss it goodbye and start over again. One guy once told me regarding RC: If you can'y afford to wreck them, you in the wrong hobby.
Click to expand...
I tried that once...............Actually it took me 5 crashes before I learn't my lesson, flying R/C planes is not at all as easy as it looks mind you they make a lovely bang when they go in.................
 
Stainzmeister said:
Bredebahn said:
If you're running on analogue then personally - unless it's vital - I would take out the reversing loop. I had one of these on the old Bredebahn and even with the LGB reversing loop modules it caused trouble (so it went!).
Click to expand...

It should be noted, for newcomers, that a reversing loop on a DCC powered layout works well (I have two such loops), provided a metal wheeled train fits within the length of the electrically separated loop section.
Click to expand...
I concur with Pauls statement. I have 3 DCC reverse chords and one is a little short for my usual train formation of loco plus 4-5 wagons. It can sometimes cause a short.

Prior to going to the DARK SIDE, I successfully used the LGB 10151 reversing sets, albiet in one direction only.

For your plan Cyril, the diamond crossing will not itself cause a short as each road will be seperately isolated from the other. I've modified your track plan to show in red where you would fit the two track pieces of the LGB 10151 set, either end of your blue dotted line. Note the track piece with the arrow has to point in the direction of the 'exit' of the reversing loop. This also shows the direction the loop operates in. If you wantuse the reversal loop in the other direction, swap the track pieces. The other way of course is to use a DPDT switch for which I can give you wirng instructions if required....


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Change to battery power Cyril - and just think of the saving on your back as well, not having to clean the track all the time !
 
well chaps, just back from t'pub and am trying to digest all your very valuable advice, that's whht G-scaleitis is all about. I'll have to sit down some evening (sober) and decide exactly what it is I am trying to do. I don't have the space for long trains and double lines to see trains always on the move, so I'd thought I'd try something else. Over the weekend I will have a go at looking at the layout outside instead of drawing blueprints. Oh well, it's fun anyway isn't it? Psssst, anyone want to buy a LGB crossover? Only joking Paul, it is going to go in there somehow or other.
Now, where's that bottle of Glenfiddich?
 
Cyril,
I've got an LGB 10151 reversing loop modules set which I bought from Gizzy ages ago when I was going to go down that route
I've never used them as we decided to concentrate mainly on steam, and just use 2 rail electrics on the original oval and isolated the extension and loop
If you want them I would part with them for a fair price
 
just looked it up
got them from Gizzy March 2011
you can have them for the same price, £20 incl UK P&P if you want
let me know
Think about it after the whisky ;)
 
Coming to this a bit late - sorry. Could I ask how you want to operate the layout? Are you running trains while sitting back and watching them or running them manually with stops and perhaps some shunting?

You mention having two controllers, and seemingly need TM1 to keep a train moving throughout the blue section, so is TM2 solely for the green section? If so it seems a bit of a waste - and how do you pass a train from blue to green? I'm not experienced with auto reverse systems and would personally wire the layout using the "cab control" method, though this would mean having to flip the switches while the trains are operating in order to run two trains on the main line at once.

I can post a suggested wiring plan for this if you are unfamiliar with the method which is basically to divide the layout into sections and feed each one through a Double-pole-double-throw (DPDT) switch. Your reverse loop adds a slight complication but there is a way of doing it. The most simple plan that gives flexibility of operation would be to have 5 sections, though you could also have sub-sections in places where you want to hold a locomotive isolated within a longer section.
 
OK in the cold clear light of morning I have thought about this whole idea, and two points from your remarks stand out. One is John (Bred) who points out the bleedin obvious, no offence, that is if you have a long train with pickup for coach lighting etc you are going to have to watch the blue flash problem. The second is that underlying Ross' comment is the basic rule, KISS. Yes. So forget the reverse loop. Haven't got a diagram (blueprint) done yet but what I will do is put the point for what was the reverse loop on the other track, use the crossover to go where the original turnout switch was going to be, join it on to the green line and perhaps add a spur up to the point where the new loop would have joined the top line, but will not now. I can then play around with that sort of yard area and develop alongside the water feature which is up there. As things develop I'll probably show some pics etc, but don't get too excited, this will take time. Thanks for everyone's comments, it has been most useful and appreciated
 
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