Signalling a Layout

Model Railroader Layouts and layout building
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Back Story: The Layout is HO, the location is central Wisconsin, time period 1932 - 1955. Traction and Steam are the featured motive power. Single track with passing sidings and one branch line. Three interchanges. Towns are (from S to N) Portage(interchange w/Milw), Westfield/Endeavor, Montello(branch line from W/E), Coloma, Hancock/Plainfield, Bancroft (interchange w/CN&W) and Plover/Stevens Point (interchange w/GB&W & Soo).

I have one interlocking tower at Bancroft, Signals at P/SP & Portage. 3 through trains daily, plus local traffic to stations. Where would you put signals? I suspect the W/E to Montello should be signalled at both ends, but anything else?

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I predict someone will ask for a diagram—lol. I may not follow your verbage well, but I would say to put signals wherever you need control. Since that’s what prototypes do–your prototype and period would have had a signal/control standards book to be more specific. You can have signals that aren’t functioning, but for appearance alone. I would expect them at all interchanges.

Richard

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A track plan… Oh you mean that amorphus shape that shifts back and forth everytime I look at the space?

I know what I want, and vaguely how I want it, but with the current basement clutter, even getting to track planning has been difficult.

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The question is WHAT kind of signals are you going to use.

Automatic block signals operate sequentially informing you how far away the train (moving in the same direction as you) is from you.

Home, or Interlocking signals are controlled by the tower. They would be protecting the interlocking plant and little more.

An intelocking plant consists of the physical track plant with its tracks and signals, and the tower with its interlocking machine and model board.

In days of old (ec etc) “Armstrtong” interlocking plants were used Actually the ones in this country were mostly made by US&S (United Switch and Signal).

In this sort of a tower there are the levers, the interlocking bed (below) and pipes that connect the pevers to the device (switch points or signal) that the lever controls. Two levers (three operations) are required to move a set of swtich points. First you must move a lever to unlock the switch, then you must move the switch points, and then you must lock them again. Each movement is protected by the interlocking bed so that levers must be moved in the proper order, and so that no conflicting alignment can occur. Only when the plant is fully alligned for a movement can the signal itself be cleared to allow a train to enter the plant. If single track lines are entering the plant the departure signal (lever) must agree with the arrival leaver of the next plant down the line. Thus there will be no conflicting movements on that track.

Here is the interlocking bed below the floor of a tower similar to the one above.

Below is the more modern (actually this is an old GRS (General Railway Signal Co.) model-2 interlocking plant at the Lasalle Street Station. Notice that the front covers have been removed and the interlocking bed is clearly seen.

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Trynn,

My layout is similar - An interlocking at a crossing has the usual ‘absolute’ signals and there are two sidings that just have ABS signals at the siding switches. Everything automatic, as the diamond is just for show. I have 8 blocks of ABS…

Jim

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Thank everyone for your replies.

I think maybe I asked the right and wrong question at the same time. Broadway they are all Armstrong Interlocking Towers. Which mean that Portage and Plover/Stevens Point are covered. Bancroft is a crossing with a Y to and from C&NW line leading not onto my main but a small interchange yard (2 tracks 7 cars each + main) so also probably an interlocking tower.

As for the rest of the signalling, I am wondering whether it would be cost effective to install semiphores at each station or just use the interlocking points and Westfield/Endeavor as section breakpoints.

I do know for operations that when the 3 through trains are enroute, All trains in the preceeding section MUST clear the main. The through trains are too long for any of the sidings to handle, so the locals have to make a run for the sidings (it should make operations interesting…as two are high speed Milk runs.)

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Are you installing CTC or ABS? The stations have nothing to do with signals, its the sidings and points where trains meet or pass or where trains enter or clear the main track.

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Manual Block

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Manual Block? NOW you are getting complicated. A manual block generally has no signals at all. A batton, flag, or token is required to authorize occupancy of the track.

In Hong Kong (back in the '60s) I watched an operation where the engineer had to have a special batton, unique to that section of track, before he could proceed. when he got to the end of that section of track, he handed it off to the train that was waiting to proceed in the opposite direction.

On British railroads, this was far more complicated, as there could be several tokens for each section of track. Thus several trains could follow one and other in a west bound direction, but before an east bound train could be given a token all of the outstanding west bound tokens had to be accounted for in the machine before it would release an eastbound token.

Of course if you want a simple signal, manually operated, such as for train orders or at a crossing with another railroad that is a simple matter.

If you have manual switch points, you will likely enough have no signals anyway.

But as you may guess, the LION is very fond of signals and of the interlocking plant. Here is a simple typical interlocking plant:

Here are the levers that control it.

The Red levers control the signals, the black levers control the switch points. Levers in the down position places all devices in their NORMAL position. (for signals that is RED). A lever in the up position puts the device in the REVERSE position.

The red levers on the left control the signals for all movements from left to right through the entire plant.

The red levers on the right control the signals for all movements from right to left through the entire plant.

The black levers control the switch points from left to right as represented on the model

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Manual block. OK they do often use the train order signals. They also use train orders or timetable to authorize movement. It’s the same style of operation as TT&TO with ABS, just with people doing the block occupancy and lining the signals. The train meets and passes are set by the orders and the block signals tell the train the block ahead is clear to move. In the US the blocks were controlled by signals and staff systems were very rare in the US. Very rare. The operators used a series of coded messages between adjacent stations to control the setting and clearing of signals.

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Here is a link with some information that may help you get started. It may have more information than you really need but should be a good starting point for planning your signals.

http://waynes-trains.com/site/Signals/GettingStarted/SignalsGettingStarted1.html