Hi Everyone,

My Dad and I made this video to show how we use Tortoise switch machines to prevent locomotives with short pick up wheel spacing from stalling on Atlas turnouts.  

I hope you find it useful and comments are always welcome!


Original Post

Cool idea, and we have a Tortoise switches on the Atlas switches on the club layout.   Looks pretty easy to do as well.

Enjoyed your video, very informative and I enjoyed watching. I think it will be a big help to all others that watch as well.

Thanks for taking the time to make it and explain all the details of making it work.

Just be careful guys. If you've never looked inside a Tortoise before, I can tell you that the contacts do not have a very high current rating. They consist of lightweight copper wipers, going over PC board traces. I don't think they were ever intended to be used with O gauge in this capacity. HO and N, no problem.

I agree using the internal SPDT switches for this use in O scale is uncharted waters.  I believe in the way we are using them we are good between 1 and 4 AMPS.  I have used them to power the frog in HO scale with up to 16V track power and engines drawing 2 amps or more in some of the older QSI decoders.  I have also used them to power the frog in O scale 2 rail without failure.  

I also received a great email from Atlas and they pointed out that once you remove the Atlas switch machine there will be 4 posts sticking out of the sleepers.  Those post are wired to the rail so you can just solder to those instead of drilling through the track.  I am going to post an update video once I get more input from other members.


FWIW, I have mostly MTH Premier PS3 and a couple of Lionel Legacy. They are all diesels and they are all under 2 amps with smoke on and somewhere around 1 amp smoke off.

I don't have any steamers, but some of those draw more amperage from what others have posted about them here.

Dear  Biggs767

 Lovely  video about  the Atlas turnout ,  thanks for share the knowledge.  Quick question about the outer rails how do you solder the wire on the rails without having the flanges from the wheels hitting it.



Last edited by nvocc5

For some reason I'm having a brain fart when I watch this..Is there a diagram around anywhere for using the Tortoises on the D.S.  I need to see it on paper,,lol  Thanks in advance


I do not have problems with the flanges hitting the wire I soldered on.  I drill a hole through the rail and feed the wire through the plywood into the whole on the rail I then solder the wire to the rail, trim the excess wire off and file lightly.  On the double slip you can also remove the atlas switch machine and there will be a small medal loop protruding from the sleeper.  I have been told you can solder the wire directly to that and it will power the rail as well.


I am not aware of a diagram out there that shows what we did.  What are you having problems with?  The wiring to throw the switch? The wiring to power the rail? What are you using to throw the switch? AIU or ASC?

If anyone using the double slip switch decides to use the closure rails (4) to improve performance you will find the (4) closure rails come with the rails connected by copper strips to the edge of the ties allowing you to solder your feeder wires directly to the copper tab eliminating the need to solder to each of the four rails. This change was added to all double slip switches starting with the last run. Earlier versions will need to have the feeder wires attached directly to the closure rails. You do not need to remove the switch motors to access the copper tabs. You can also visit the Atlas website to find wiring instructions on using the non-derail circuit board item # 6924 to provide the needed wiring similar to the Tortoise motors used with this thread. If anyone has questions on how to wire this application you can contact me at 908-687-0880 ext 7142. If anyone will be attending York this week I will be there for the show.... stop by.

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