Layout wiring....question about how to run.

What system are you going to run? Conventional, TMCC, Legacy, or DCS?

That would help tremendously.

If you are planning to run MTH DCS system, you should research suggested wiring ideas.  If you are running conventional or Lionel TMCC /Legacy , your idea of using one ground (neutral) should work just fine.  Since you will be running three tracks, I would use a larger conductor for the common since all the power from each track will be flowing through it. Based on the size of your layout, I would use 12 gauge for the common.   With the larger conductor, you can also use the same ground wire for everything else you power on your layout (signals, lights, accessories, etc).

Also, if I were working on the layout, I would go ahead and drill larger holes (1 to 1 1/2 inches) close to the from of  the layout.  Down the road with lights,  switch machines, accessories and other items, you will be amazed how large the bundle of wire will be.  I suggest close to the front because once you start storing boxes under the table, it will be so much easier to work with.

Looks like it is going to be a very nice layout.

Happy railroading,

Don

If you run DCS, do not use a common ground wire for the three main lines. 

Your accessories can use a common ground.

I have Legacy, DCS, and I do have some old conventional engines.   I have MTH 4000, Lionel 4stick, I have 4 180 watt blocks and 4  135watt blocks.  I currently run Legacy thru the DCS TIU.  I am open to all suggestions.

I am open for any help with this wiring.  If you live with an hour or so of Greeneville, TN, come on by, all train hobbyist are welcome. Looking to have blocks lights, switch lights, Roundtable/turntable.   I am interested in starting a club if anyone would like to assist me with a charter I could change the names to protect the innocent. Normal Club Policies, rules, etc.  Thank all of you for your help.

Spend $15 and go on the MTH site and order the MTH DCS WiFi Companion. https://www.mthtrains.com/dcs It will describe the perfect wiring for everything including accessories and Turntable. It will be the best $15 you ever spend.

With that being said you need to do Star Wiring and wire each loop independently so you can run conventional at the same time as DCS and Legacy. Every 12 to 13 sections of track Regardless of length of section you will need to install a feeder and isolate from the next group of track. Get the book as it is the Bible.You can always come here and ask questions if you get stumped.

Curtis

Go to an Office Supply Store (I happen to find some at Dollar Tree on a Lark) and get some tags on a string and use them liberally.  I am using 2 conductor thermostat wire for my switches.  I use a common neutral (Ground) so the third wire from the switch gets connected to that wire all over my layout.  Thermostat wire is solid conductor and does not bend well but 18 AWG is not that bad.  Having said that, use stranded wire where ever possible.  It is easy to work with and there are a number of different ways to join stranded wire, whether T-Taps or other crimped connections or for the skilled, soldered joints.

I forgot to mention.  For wire guides under the layout, you can drill numerous holes through your 1x cross members or I used Conduit Clamps screwed to the bottom of my cross members and all my wiring goes through these clamps.  If your really neat, run all your power wires through one.  Mount another next to the original and run your switch wires through that one and similarly any wiring you use for building lighting or accessories through yet another.  I did not do this originally.  Wish I did as it would have saved some trouble shooting time re-fishing wires.  If you are on a limited budget, I know a person that used Hangers cut in two to fish his wire through.