Wiring block sections

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I have layed my track and separated by blocks. Now it's time to wire each block. I'm running HO scale and the longest block is 12 ft with no interruptions. Most are 3 to 6 ft long with a switch on one end. I'm planning to use 18ga stranded wire for the long block for the 12 ft block, then using 20ga stranded wire for the short blocks. I will be running DC for now, but plan to convert to DCC later. Are the wire sizes mentioned above adequate for DCC? The rail drops are also 20 ga.

D&J RailRoad

Professor of HO
I think you might do better to use 16 gauge wire for the buss. Run that under the track road bed and use 20 gauge for the actual track connections.

Iron Horseman

Well-Known Member
I have layed my track and separated by blocks. Now it's time to wire each block.
Since you are wiring for DC, all the DCC bus "specifications" kind of go out the window. I would be certain to put the feeders in the center of each block. Except for the longer 12 foot block I would put in two feeders such that the train will not be more than 3' from power. I think the wire gauge should be fine. The last 12x12 layout I did I used 20 gauge twisted pair everywhere, there is no bus. Each block wires go directly back to the power.
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Thanks for the info. Can I run all the bus wires together? Or should I route each pair separately? I will be running twisted pairs for bus wires.


Well-Known Member
You mention having a turnout (track switch) at one end of each block. Unless the point end of each turnout points away from the length of the track, you will need to attach the wires to the point end of the turnouts. This would mean NOT attaching the wires to the middle of the block...unless you place insulated rail joiners between the wires and the frog end of the turnout, and then run jumpers to the point end of the turnout. Probably a simpler solution would be to make the turnout part of the adjacent block. OTOH, if the turnout is oriented with the points toward the block wires in the middle of the block, no problem. When you convert to DCC, you can retain the capability to run on DC. Just connect the main bus wires to the center contact of a DPDT toggle switch (or a rotary), then connect one side's contacts to the DC powder pack and the other pair of contacts to the DCC pack. Remember that most DPDT toggle switches connect the contacts on the opposite side of the switch, so if the toggle is thrown to the left, the right pair of contacts are connected to the feed contacts (middle), and if the toggle is thrown to the right, the left pair are connected. Mount the toggle on your control panel, properly labeled. Hope this helps rather than confuses.
Hi TGeek. Unless your planning to go DCC later, that by 'later' you mean years, why not do it now ? Or, is cost of DCC control, such as NCE / Digitrax, other, prohibitive at this time ? If so, I can certainly 'railate' to that !..The NCE PowerCab does a great job on small to medium size layouts and must hover around, what, $150-$175 today. M, Los Angeles

Iron Horseman

Well-Known Member
It is very easy to make DC block control wiring that will work for DCC. It is not easy to make DCC bus type wiring that will work for DC block control.

The disadvantage of going DC first and then converting is that in-the-end one has incurred the cost of both. In my opinion, the real cost of DCC isn't the controller but rather the cost of dollars and time getting decoders into the locomotives. I've been on the DCC road for over 25? years now and don't even have 1/2 the fleet converted yet.
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Well-Known Member
I was perfectly (?) happy with a DC layout and engines...until my wife thought it would be neat to have sound on some of my trains! So, I got me an MRC Tech 6 6.0 and one (1) diesel with sound. Eventually changed over to an NCE Power Cab, and started converting a steam locomotive. No, they aren't cheap, and neither are the factory equipped one. First, there's the decoder. Then the keep alive capacitors, speaker, quick-disconnects for the 5 or 6 wires, plus a 2-wire for the headlight, in case you have to remove the boiler from the frame. And, of course, the 3 or more hours it takes to modify things and solder connections. We'll, I just finished with my fourth, and...for the foreseeable future...last one...I think!
Iron H, that's your chosen method, and that's fine. I instead mothballed my analog stuff (only about 5 HO / 7 N), bought an NCE PCab, an HO Bmann Consolidation DCC/sound on board, and never looked back. I'm thinking the OPer's situ might be similar to mine. That's all. M

Iron Horseman

Well-Known Member
I'm thinking the OPer's situ might be similar to mine.
Yup, you are probably right, everyone's situation is different even though that is easily overlooked in both reading and responding to forum posts (and not just for toy trains :oops:). After 20-30 sound conversions I made a rule to always buy "new" locomotives with the factory sound already installed. As trailrider outlined the conversion is often painful.
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