Signals and blocks for a reconstructed route

[RichardAJensen]

Sorry I keep adding new topics...

As I'm rebuilding a stretch of abandoned route, all of the signals are long gone.

What resources--if any--are there for recovering the original signal locations? And if I have to start from scratch what would be a good rule of thumb? I have a book of track profiles, and there are some notes on each sheet that I can't quite suss out.

I've got a very sketchy understanding of traffic control, just the basics: That tracks are divided up into blocks, and that only one train at a time can be in a block. However, I don't know how big the blocks were on this route, or where the signals were placed.

[ebnertra000]

It depends on the location, and the era, as to what sort of signals were present on a route, if any. Most modern systems use blocks of around two miles, but many older systems used lengths from two or three miles down to a mile or so. I know of a line in this area where foundations of the now-long-gone signals are still present, and can possibly be seen on aerial images, so that may be an option. Are the notes in the track profiles unreadable, or just of unknown purpose? More modern profiles almost all document signal locations, though earlier ones may or may not

[rockislandfan]

I am not very familiar with your route but their my have been many miles of "Dark Territory" on it, at least in some areas. So that means no need for signals in those areas if that is the case. That would be the first thing to research. I have seen several photos of the Milwaukee Road line to Rapid City and I don't remember seeing any signals, at least on the western end. But I am not definite that they didn't.

[eolesen]

Sorry I keep adding new topics...
What resources--if any--are there for recovering the original signal locations? And if I have to start from scratch what would be a good rule of thumb? I have a book of track profiles, and there are some notes on each sheet that I can't quite suss out.

All the track profiles I've reviewed show signals if they existed. Where is your route located?

Worst case, come up with whatever works for you. I've added signals to what was track warrant territory, mainly to support AI trains (which don't work too well without some rudimentary signaling).

[RichardAJensen]

I am not very familiar with your route but their my have been many miles of "Dark Territory" on it, at least in some areas. So that means no need for signals in those areas if that is the case. That would be the first thing to research. I have seen several photos of the Milwaukee Road line to Rapid City and I don't remember seeing any signals, at least on the western end. But I am not definite that they didn't.

This turned out to be the case.

The Dakota division route profile book also includes the Milwaukee Road's mainline, and I was able to find signal notations there.

I'm not sure how to read them, but they are there.

Screenshot 2022-07-04 200127.jpg

[eolesen]

That looks easy to miss if you don't know what you're looking for.

My guess is 138R is the righthand side (engineer's) of the track, 138LA and 138LB are on the left side (conductor's) of the track.

[ebnertra000]

I think those identifiers (138R, 138LB, etc.) are just the names given to individual signals on a CTC board. Since the switch is not only fully protected by signas, but also powered, this is almost certainly a CTC control point. Unfortunately, this doesn't tell you what they could show, or what they looked like (signal head type, high vs. dwarf). But, barring some actual images or more detailed information, we can make some educated guesses:

The majority sidings in this era weren't 'controlled' - there was no track circuit in the siding, and thus, the dispatcher couldn't see what was there. As a result, entry to the siding would be made on a Restricting signal, rather than standard diverging signals.

Signals on sidings were often dwarf signals to better distinguish them from mainline signals.

Milwaukee got most of their signal equipment from US&S, which narrows the possibilities of what was used here.

They also used the Consolidated Code of Operating Rules, which details a default set of signal aspects, and I'm pretty sure MILW used them as-is, or nearly so.

That should be a decent start...

[RichardAJensen]

I think those identifiers (138R, 138LB, etc.) are just the names given to individual signals on a CTC board. Since the switch is not only fully protected by signas, but also powered, this is almost certainly a CTC control point. Unfortunately, this doesn't tell you what they could show, or what they looked like (signal head type, high vs. dwarf). But, barring some actual images or more detailed information, we can make some educated guesses:

The majority sidings in this era weren't 'controlled' - there was no track circuit in the siding, and thus, the dispatcher couldn't see what was there. As a result, entry to the siding would be made on a Restricting signal, rather than standard diverging signals.

Signals on sidings were often dwarf signals to better distinguish them from mainline signals.

Milwaukee got most of their signal equipment from US&S, which narrows the possibilities of what was used here.

They also used the Consolidated Code of Operating Rules, which details a default set of signal aspects, and I'm pretty sure MILW used them as-is, or nearly so.

That should be a decent start...

This site has signal configurations for a variety of north central railroads, but not the Milwaukee Road specifically (despite the page's title):
https://www.railroadsignals.us/rulebooks/milw/index.htm

And this site has more info: http://www.lundsten.dk/us_signaling/...stp/index.html (although I believe it has some mistaken information about the names and corporate history of the line)