How to Install Uncoupling Magnets for Model Trains

  • 01 of 05

    Magnet Location Is Important

    Train set
    onfilm / Getty Images

    Many model knuckle-type couplers rely on magnets for semi-automatic uncoupling. This allows cars to be uncoupled without reaching in and using your hands. A variety of uncoupling magnets is available, suitable for many scales and track types. Installation is easy and takes just a few minutes.

    Magnets add a lot to your operations. Choose the location of your magnets carefully, especially if they will be hidden.

    Magnets are common on sidings and yard tracks where cars are frequently uncoupled, or spotted. But remember, magnets don't discriminate. It's easy to place magnets where they uncouple cars more often than you'd like them to. Here are a few tips that will help you get the most out of your magnets:

    1. Be clearance conscious: Place magnets past the clearance points of switches. This can be easily tested with a pair of cars before installing the magnet.
    2. Avoid curves: Couplers generally function better on straight track than curves. The same is true of real trains.
    3. Mainline magnets: Consider an electromagnet on mainlines or heavy-traffic areas where accidental uncouplings would be a problem.
    4. One magnet, many tracks: Placing a single magnet at the entrance of a yard ladder can allow you to uncouple cars at a single location before spotting on the proper track. This application works best when the ladder is placed on a grade allowing the cars to be sorted by gravity. A “hump yard” like this avoids all of the reverse moves normally associated with switching.
    Continue to 2 of 5 below.
  • 02 of 05

    How to Install Uncoupling Magnets

    Magnet Installation
    Ryan C Kunkle / The Spruce Crafts

    Once the location is chosen, installation is straightforward.

    Some magnets sit above the ties, and others are designed to be hidden below. Both work well. Above-track magnets are easier to find but harder to disguise. Below-track magnets don’t mar the finished scene but how will your operators know they are there?

    This installation uses a magnet made by the manufacturer Bachmann Trains. These magnets are designed to fit under the firm’s line of integrated roadbed track, but they will work on conventional track sections as well.​

    If you are using foam or cork roadbed, installation of these or similar products goes quickly:

    1. Trace the magnet on the roadbed.
    2. Make a hole with a hobby knife and chisel.
    3. If necessary, shim the magnet to the proper height (flush with the bottom of the ties) with cardboard or plastic shims.
    4. Use the adhesive side of the magnet to help align it with the track.
    5. Lay the track over the top of the magnet and test.

    Below-track magnets are easiest to install as you are laying track. If your track is already in place, gently pull it up where you want the magnet and relay, or opt for an above track version.

    Continue to 3 of 5 below.
  • 03 of 05

    Closed Knuckle Coupler

    Closed Coupler
    Ryan C Kunkle / The Spruce Crafts

    When not over the magnet, a model knuckle coupler will be closed like this.

    Continue to 4 of 5 below.
  • 04 of 05

    Open Knuckle Coupler

    Open Coupler
    Ryan C Kunkle / The Spruce Crafts

    Once spotted above the magnet, the knuckle coupler will open, and two cars can be separated.

    If cars are pushed together on top of a magnet, they can be pushed without coupling.

    Continue to 5 of 5 below.
  • 05 of 05

    Marking Hidden Magnet Locations Under Finished Track

    Magnet Marker
    Ryan C Kunkle / The Spruce Crafts

    Once the track is finished, operators will need a clue to know where they can uncouple trains.

    To finish your magnet installation, paint, weather and ballast the track as usual.

    Mark the location of the magnet. Bachmann includes a brakeman figure with the magnets used here for this purpose. These would get repetitive on a large layout.

    A small spot of paint on the rail, a special color weed or tuft of grass, scale signs, or other markers could also be used.

    Your magnet is ready to go. Grab an empty car and spot it on that siding with confidence and no hands.