Thursday, November 2, 2017

Hand throws for turnouts

For the Battle Mountain industries I want to have a hands on operation so the turnouts will be controlled by push / pull rods from the fascia.  This is something I had done on the Los Angeles Terminal District layout and saved all the components for use some day.  That day is here.

The control linkage goes to a DPDT slide switch that has a hole in it for the wire and another for another for a wire that goes up to the turnout.  The switch will hold the turnout points in position and provide electrical switching for frog power and for a turnout position indicator on a panel.

On the LATD layout and Ntrak modules I had first used glass beads attached to the end of .040 piano wire.  Then I switched to using push pin heads with the pin part removed.

Because I am adding a finished fascia to the front after installing the section into the layout this was going to require a different solution because I was going to need to remove the knob to put the fascia on.

One of the common sizes for the shafts of electronic controls is 1/8 inch.  A short length of 1/8" brass tube was mounted at the end of the .040 music wire by notching one end of the tube, making a bend right at the end of the wire, then sliding the tube on from the other end until the bend stops it and rest in the notch.

Super glue can be used to attach the two metals securely and small set screws on the knob will hold it to the brass tube.
A knob was borrowed from a Digitrax throttle to test this.  After confirming that this would work, I visited an electronics surplus store in my area and picked up 20 similar knobs so I will hopefully have enough for the whole layout.




The knob can be removed to allow for the installation of the finished fascia and a small control panel after this section is installed in the layout.

Enough space is left between the knob in it's pushed in position and the frame to allow for the thickness of the fascia and control panel.

More on the control panels and indicator lights in a future post.

9 comments:

  1. Very timely post Brad. I like that idea very much. Nice and small and not in your face. What bracket did you use to mount the slide switch. I used aluminum on my Lost Creek On30 layout and it is a pain to work with.
    Rod. email address: the_warrens@bigpond.com

    ReplyDelete
    Replies
    1. Hi Rod,

      I started out using some aluminum mounting brackets left over from something I had installed somewhere. I have also made my own from aluminum L bracket from the hardware store. I actually enjoy working with aluminum.

      Delete
  2. Hi Brad. I have the same style of push-rods (with a simpler mechanisms) on my layout, using glass beads. To prevent protruding rods from being damaged by operators, I mounted them flush with the fascia in a way that allows me to remove the fascia without affecting the turnout control. Details are here on my blog:
    https://gulflines.blogspot.com.au/p/turnout-pushrods.html

    ReplyDelete
    Replies
    1. Hello Ron,

      Wow we do have something similar don't we. Around most of my layout there is a workbench or something that sticks out further than the bench work I don't think the knobs sticking out will be a problem.

      A funny thing did happen once with those blue push pin knobs on one of my Ntrak modules. The club was using push pins to hang the drapes and during the tear down one of the guys was pulling on one of my turnout push pins for all he was worth thinking it was a drape pin. It was always a little bent after that but still worked just fine.

      Delete
  3. This comment has been removed by the author.

    ReplyDelete
  4. Brad I am going to be using your design for turnout control. Instead of wiring a bipolar two colour red green led I am planning to use two green LEDS so only only the one led is one indicating right of way while the other is off.

    Do I wire the DPDT slide switch as fallows. One side of 3 contacts would be positive rail lead,center is from frog,bottom is negative lead. The other side 3 leads would be for LEDs wired as follows.

    Top contact one positive lead from 1st led. Middle contact, both negative leads from both LEDs wired to appropriate resistor. Bottom contact has positive from the other led. I am correct in the wiring set up.

    Do I also need to x wire top left contact to bottom right contact and top right to bottom left to make this work.

    Any suggestion or wiring diagrams would be a very helpful.

    ReplyDelete
    Replies
    1. Hi Peter,

      Yes, that will work well with the two green LED's. I had done it that way on two past layouts.

      One set of contacts on the switch is used for the turnout frog with the center going to the frog and the rails being connected to the outer posts.

      The second set of contacts is for the LED. In the post "Single turnout control panel" there is a wiring diagram showing this.

      Delete
  5. I did go over that post. So if I understand it correctly I can't have the track power the LEDs i have to have a second power unit.

    I was planning on using a 12v 1.2 amp power source as I am using that to power my tortoise machines for the main line switches.

    Is a 12v supply ok for this application. And how would I wire that to the switch. Do I solder it to the switch leads or connected to the barrier strip?

    ReplyDelete
    Replies
    1. I would suggest using a 12 volt DC supply to power your led indicators. Each LED will need to have a resistor in series with it. The value of the resistor would depend on the LED and how bright you want the light to be. 270 ohm would be a minimum. I tend to use terminal strips as shown on some of my blog photos and make my connections to those.

      Delete