Wiring a model railroad

Dean’s been in touch with a fabulously clear ‘how to’ on something that is always popping up on the blog: wiring a model railroad.

“Al, greetings from Dean in New Mexico. Thanks for all your good work supporting the hobby!

One of the bigest bugaboos of people starting out in model railroading is wiring.

So this is a short tutorial on wiring the track, testing it out, and soldering.

To start, I recently was asked “why do you use so many feeders in your model railroads. I’ll begin there.

Here’s a simple loop layout. One of the two rails of the track is black, the other, red and the blue slash lines indicate rail joiners between the track sections. The circles with arrows represents a voltmeter measurement and they are green idicating correct voltage at any point you might measure.

wiring your model railroad

A bad or loose rail joiner will limit power to some parts of the layout, but with one bad joint you still get power everywhere.

wiring your layout

You can have up to two bad joints if they are on different sides of the track. You can see that in the diagram below–all sections of the track get power from one side or the other.

wiring your model train layout

But, if you have two bad rail joiners on the same side of the track, you will get lower voltage (loco will slow down) or even no power (loco will stop) in the section in the middle (indicated with a red circle).

wiring your layout

You have two options to repair the track: You can solder the bad rail joiners, or you can add a set of feeders, or jumper wires to the bad section.

wiring your layout jumper wires

People have different philosophies on how many feeder wires to add. Some go as far as to add a feeder to each section of track.

In my current Conejos Valley Railroad, I’ve put in four sets of feeders as you can see.

Then if a siding or other section of track goes bad in the future, I’ll add a feeder to that section.

wiring your layout jumper wires

The photo below shows the four sets of feeders coming back to the same point. I chuck the two wires in a drill with the other end held in a vise, then run the drill slowly to twist the wires together.

feeder wires for model railroad

Here’s the terminal block where the sets of wires are connected to my power supply.

terminal block for feeder wires

Testing the track. Here’s an inexpensive voltmeter that you can buy on Amazon for around $12.

If you are running DC power, set it as shown on 20 volts DC. I’m testing it out with a 9-volt battery, but you can measure your voltage easily at various points on your track to look for bad sections.

testing wiring model railroad layout

My railroad is DCC powered. DCC is actually alternating current, so for that set your volt meter to 200 V AC.

testing model railroad track wiring

Soldering is easy if you have the right tools and solder.

You can get a soldering station such as the one below for $40 to $50 on Amazon.

You can vary the temperature of this one (I use 200-220 C) and it comes with rosin core solder that is safe to use for your track or wires.

The rosin in the core helps the solder to eat away corrosion on the metal. Don’t use acid core solder which will eventually corrode the metal.

soldering track wiring for model railroad

To solder anything, first “tin” the solder point by touching the hot tip to the end of the solder wire.

This coats the point with a thin layer of liquid solder to help heat transfer. Then heat the metal and after it gets hot enough, feed the solder to the metal.

soldering track model train

If you’re careful, you can add jumper wires to existing track after it is put down.

But the best way to add jumper wires to a layout is while it’s under construction – as you lay the track you can add hidden wires to the rail joiners.

The wires can be soldered onto the rail joiners at your workbench by holding them in a short piece of track. Solder a blob of solder to the joint, tin the wire and then solder it to the joiner.

soldering jumper wires on model train track

Test the finished assembly to make sure its sound, then slip it onto the rail end as you lay down your track and pass the wires though holes in the track support.

soldering jumper wires to track

I’ve put out a YouTube video that shows all of this in more detail:

Hope this helps.



A huge big thanks to Dean for sharing his ‘how to’ on wiring a model railroad.

I have to say, I think it’s a wonderfully clear post on wiring.

Please do leave a comment below, I’d love to hear your thoughts on this one.

That’s all for today folks.

Please do keep ’em coming.

And if today is the day you get started on your layout, the Beginner’s Guide is here.



PS Latest ebay cheat sheet is here.

16 Responses to Wiring a model railroad

  1. Howby says:

    The whole point of dropper wires is to ensure a reliable supply to all parts of the layout because rail joiners cannot be relied. ….it is a waste of time soldering droppers to the joiners . Best practice is to solder to the rails.

  2. Macbear says:

    Beware not all “voltmeters” are the same. I bought a multimeter that seemed to test conductivity from the description, and from a reasonable manufacturer. Alas, that was one thing it didn’t do …

  3. Nigel Crowther says:

    Thanks very much Dean,great tips for powering the track,will use them for my railway track.

  4. Stephen Hill says:

    Great information , thank you for sharing your insight . I’m a beginner and rather inexperienced in electrical stuff so you have enlightened me significantly with your tutorial. Patience and practice seem to be key in this hobby , combining those with the magnificent info and input from someone like Dean is very encouraging … I feel like I’m learning, thank you .

  5. Rich B. says:

    Meters… always liked the Simpson 260 which was analog display. Fluke has been my standard now for decades, digital. Polarity makes no difference, if wrong will tell you so with correct readout regardless.

    As far as rails or joiners to soldier, jury’s still debating which might be best I’d say:
    1) Is flex rail in use or all plug and play short pieces?
    2) Nobody mentions heat expansion and contraction of rails. Joiners serve as expansion slides to be considered as prototype does.
    3) The 4 conductor telephone cable works perfect for rail soldiering either side of joiners. Small solid strand 4 conductor stuff, color coded even. This can carry 120 volts AC, no problem. Yes, know about the hard way getting zapped (by accident, alarm systems and such generated on pole lines). Before “cell” of coarse.

    Find no fault with joiner jumping, good topic and good idea. May even be the better fix, can’t really say.

    Regards, Rich

  6. Greg Marples says:

    I use flex track and solder the joiners. Still solder on feeder wires every six to eight feet, as well as after every switch. DCC layout, so I don’t have to worry about separating blocks. Wide curves, glueing to cork roadbed and a fairly constant temperature environment should account for any expansion issues, I think.

  7. Joe Randazzo says:

    I’m a newbie. Thanks, the subject was just in time

  8. Brian Olson says:

    Thanks for the focus on wiring, especially good for those starting out in this hobby. Trains don’t run without electricity. It can be frustrating but worth the effort and time.

  9. Rob McCrain says:

    Dean’s wiring advice is good advice. Owning a volt/ohm meter or multimeter and knowing how to use it is something all model railroaders should have and know how to use. I use mine all the time when setting up or diagnosing electrical troubles on Farland and the N scale efforts. If you don’t know how to use one, you can google it, youtube it or read the instructions that come with it. The most useful function is the continuity testing capability. Rob McCrain

  10. EARL S CORY says:

    Solder to the rails, not the jointers. You are still relying on a mechanical connection for conduction.

  11. Mike Balog says:

    Good Basics of Model RR Electrical Wiring… ALSO,,, I have a friend in our Model RR Club here who has an O27 Scale Layout. He brought in a New Locomotive to test on the layout… It Had it’s Own Rechargeable Lithium Battery Power Pack inside the Diesel Locomotive Shell Body. My Guess it was a Williams Brand. It ran on his layout using that internal power pack and a Control App that was downloaded on his Cell Phone! SO, you can RUN locomotives on your Layout that are battery powered! From Mike In N.H. U.S.A.

  12. Chuck Holsclaw says:

    I have a dcc layout. I have my joiners soldered more for alignment than conductivity. I solder feeders to the rails. Dcc needs a good signal otherwise the decoder won’t respond properly. The further you get from the command station you need feeders there to prevent voltage drop and the rails need to be clean.

  13. Red says:

    To avoid voltage drop and dead track, I ran feeder wires under the table underneath the track. Then every other 3′ length of flextrack I used powered track connectors and ran them under the table at the junction and tied them into the “bus” running under the table! Works fantastic!

  14. Gary M From Long Island says:

    Dean…. If not the best then one of the best electrical instructional blog and video I have seen.

    Fantastic job. I have stored this in my library if “HOW TOs”.

  15. Johnstevens4800@gmail.com says:

    Great job on the wiring thanks

  16. John Lofgren says:

    I absolutely enjoy your varied presentations. The people with whom you correspond regularly are often extremely good a and practical in their discussion of model railroading issues and problems.
    I moved to a new location but am pretty old so I;m still thinking about whether I should get back “in the saddle” as it where. My interest won’t change – no matter what my decision is.

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