I am getting quite close to putting down track for an HO scale, DCC 13’ x 30’ around the room double track main line layout. I know I want to include a block signal system, but right now, I need to put my cash flow into things like track, switches, switch machines, etc.
My question is, what should I be doing at the track laying stage to make things easier when I add my signals down the road? If I isolate my mainline into blocks, can they still run off the same bus wire, or would that effect my block occupancy detectors?
I am still researching and trying to learn all I can about signals, but I am hoping to avoid any major mistakes and not be kicking myself down the road.
It really depends on where your block detectors will be located. They have to be between the bus and the section you are detecting - if you scatter them about under the layout, you can keep the bus wires and connect the detectors ‘out there’ under the layout. Use a sub-bus arrangement if the detected section has more than one feeder - say #12 for the main bus, tap off a #14 to which the detector connects to, and that in turn connects all the track drops for that detected section.
I plan to use Rob Paisley’s detector circuit on my layout, it’s cheap and easy to build. Plus there is NO physical connection between the DCC track power and the detector, it uses a pulse transformer through which you wrap a turn or two of the wire leading to the track you are sensing. Also, with diode-drop type detectors, if you have sections that are NOT detected, you should include the same types of diodes in the track wiring so those section don’t run at a different speed. The sections with the diode detection will run with a slightly lower track voltage because of the voltage drop.
The obvious part is where are the block boarders going to go. You probably will have future revisions, if you have enough feeders in place, you can simply cut the rail with a dremel attached with a cuttoff wheel, fill in the gap with styrene or leave it open then touch up the scenery.
If you don’t have enough feeders it will be more difficult to add after the addition of scenery. Wire in lots of feeders before doing scenery if possible. It will help with DCC if you feed each peice of track without forcing the track to conduct more than 3’.
As for wiring, you can start by simply connecting the feeders to a bus pair. When you add detection, remove the bus and add a new one that only goes to the block detectors. Next run wires from the detectors to the feeders for each block. If you have the sudden urge to run trains NOW!, then you can simply hook up only a few feeders that are needed. This way you won’t have to be without running trains for long periods of time while you are doing projects around the layout.
The wiring is pretty simple, as long as you use good wiring practices. The bus wires should be heavy gauge. (14-10 AWG) Feeders should be 24 gauge or thicker and as short as possible. (Under 6") Soldering is usually the best option for wiring feeders and bus wires together, “suitcase” connectors are second best. (though they are nice in tight areas where soldering is more difficult) Terminal blocks are very nice because rewiring is a snap.
For turnout wiring, I perfer to use non insulated turnouts and gap the closure rails and gap the frog rails where the signal will be placed. I detect some turnouts so they won’t accidentally get thrown under a train.
My biggest question is how are you going to signal your railroad. If you don’t have your mind made up, I suggest C/MRI found at www.jlcenterprises.net I personlly use it and love it’s flexiblity. Cost wise, it’s as low as $1 per input or output. Meaning a tortoise or pushbutton will cost
Thanks to both of you for your replies. Marc, I have not thought about what type of signal system I will use, but I will definitely look into the JLC system. I also need to dig out that MR series from a couple years ago on signal systems. My biggest question was if I can get running now (or soon) and convert over to a signal system later. It sounds like the answer is YES.
here is a website that has a really good train detection circuit and a step by step instruction on how to build one…it includes block signalling and siding signaling http://www.gatewaynmra.org/detection1.htm …chuck
The answer is YES. The matter at hand is how easy will it be to convert. For instance, using all the same color wiring or inconsistant wiring is like shooting yourself in the foot. The use of consistant wiring will make the conversion easy and also trouble shooting much easier.
Keeping a buzzer on the bus is a good way to prevent shorts. Anything such as a miwired feeder pair, non insulated bumper post, a #2 phillips screwdriver layong accrosed that track will cause problems when you try to run. Just remember to remove it before hooking up DCC booster.