Atlas under table switch machines (Under 2+ inches of foam)

Discussion in 'N / Z Scale Model Trains' started by timwatson, Apr 6, 2005.

  1. timwatson

    timwatson New Member

    Hey gang I wrote a small tutorial on the Atlas forums awhile back (like a year or so). Unfortunately Atlas kind of went on hiatus and now the tutorial is gone so I was reading in the academy and I gained some insight from that, so I thought I would post this tutorial here. Hope it will be found useful enough to make it to the academy.

    A picture is worth a thousand words so here goes:
    This is an illustration of an atlas under the table switch machine being used under approx. 3 inches of foam.

    What you will need: Piano wire (flexible steel wire), brass tube stock (used as a sleeve-goes outside the piano wire), ho scale atlas under the table switch machine. Some soldering skills.
    1. The brass tube is similar to a lawnmower choke cable. So the piano wire goes inside the brass tube. Make sure the brass tube and the piano wire are at close tolerances.
    2. I just checked the size of the brass tube and it was 1/16" and the piano wire fit inside the tube.
    3. Next you need to modify the atlas under the table machine. It has the "neck" that goes the height of the subroadbed. It is the part that connects to the turnout. In our example we will need to cut that OFF. See the below picture.
      Be careful when cutting the collar off. It is a delrin-type plastic so it is slick and brittle. I used a dremel cutoff disk.
    4. As you can see in the picture that you will need to drill a hole in the "nub" that is left over from the collar.
    5. After the machine is prepped then you will shove the brass tube through the foam. I mean shove it. It is sharp and will go right through the foam but you will need some force.
    6. Have the brass tube approx. a 1/32 or 1/16 of an inch above the foam top. This will make the brass tube and the top of the ties have the same height. The placement of the tube will be right in front of the throwbar for the turnout. Make sure the brass tube is placed on one side perpendicular to the throwbar. If this is confusing then just follow the picture.
    7. Go underneath the layout and cut the brass tube flush to the bottom of the foam.
    8. Next bend the piano wire into a square shaped U. Slide it down into the brass tube and align it with the hole in the turnout throwbar.
    9. Underneath the layout will be the remainder of the paino wire. Leave aprpox.1"-2" to play with and then cut off the rest.
    10. Disclaimer: I am pretty good solderer. So having said that if you are not very good with a soldering iron then bend the wire instead of soldering 2 pieces.
      If you are going to solder then leave the 1-2" alone and then take some of the left-over piano wire and make an "L" approx. 1/4" long. Solder that wire to the 1-2" that is in the brass tube. The "L" will be parallel to the foam. See the picture. You are working on the linkage to the switch machine.
    11. Now slide the switch machine so the "L" fits in the switch machine hole you drilled earlier.
    12. Now you are connected. Next it's time for adjustments. I pinned the switch machine to the foam and fired it up.Too tight on one side not tight enough on the other. Adjust and try again. When you have it working properly glue the switch machine to the foam.
    13. Viola you have an inexpensive switch machine through many inches of foam for approx. 5 or so bucks.

    Hope everyone enjoyed.
    Tim Watson
  2. MasonJar

    MasonJar It's not rocket surgery


    Nice work! Great how-to and definitely a possibilty for The Academy.

    One question... Have you tried this with the tube coming up between the rails?

  3. timwatson

    timwatson New Member

    No I have never tried that. My thought is the ballast might get in the way but all the same principles apply. Andrew thank you for the compliment. I was wondering if anyone was very interested in the how to.

    Thanks again, Tim Watson

Share This Page