NW Modeling List nw-modeling-list at
Wed Feb 10 20:01:51 EST 2016

I agree with Jim, that this is a good way to install a tortoise after the fact. But there are a few details omitted. The distance between the throwbar and the tube through the roadbed is usually about ½ to 5/8 inches (dimensions are for HO layouts). That allows the mechanism to have enough throw without binding. Underneath the layout, you then bend the piano wire 90 degrees to form a bell crank. From the lower horizontal, I then bend down another 90 degrees and attach to the tortoise. I try to make the upper horizontal and lower horizontal about the same length. I agree that you should go up in size on the piano wire, as this mechanism will need to be stiffer than the provided wire.


Another alternative is to drill a large hole (usually ¼ to ½” depending on thickness of roadbed and sub-roadbed) to the side of the turnout and in line with the throwbar. You can then use the tortoise recommended configuration with an additional bend at the top of the wire (again going up in size). The drawback here is then hiding the hole in the scenery without interfering with the mechanism.


For the turnout in your picture, could you mount the tortoise higher and behind the rock face scenery with a throwbar extending out through the scenery? But again, hiding things like that can be a problem.


It’s a lot easier to mount in their recommended configuration. But that does require planning ahead. And the club layout where I do this did not always provide the forethought when track was laid.


Don Trettel

Fall City, Wa.


From: NW-Modeling-List [mailto:nw-modeling-list-bounces at] On Behalf Of NW Modeling List
Sent: Wednesday, February 10, 2016 3:16 PM
To: NW Modeling List
Subject: Re: THE SIX P'S




I would suggest that you power the turnouts; I have used the Tortoise by Circuitron machines exclusively and always been happy with them.


Without ripping up anything, I would first get some brass tubing; the diameter is not real important but it must be wide enough so the piano wire for the Tortoise can move freely.  Next, I would drill of hole of the same diameter as the brass tubing either in front of, or in back of, the throw bar to the turnout, and centered between the rails.  You would then insert a length of the brass tube in this hole.  The length will be just long enough to pass through your roadbed and sub-roadbed.


You will need to bend a throw rod from the piano wire; I would suggest using a slightly larger diameter of piano than what comes with the Tortoise; you will make a 90 degree bend that will insert into the center of the throw bar; the next 90 degree bend will be the distance between the throw bar and the brass tube; then a "long leg" of the wire goes down the through the brass tube to the switch machine location.  You might practice bending these throw rods with brass rod to get the feel of it; then you could use that as a pattern for the bending necessary in the piano wire.


Be sure there is no ballast in front of or behind the throw bar; if there is, you can usually remove it by wetting it with water and detergent, leave it soak, and use a small blade screwdriver or other implement to dig out the ballast.


Did you dig out the roadbed under the throw bar location before you installed the turnout?  I usually cut out a portion of the roadbed (homasote) at the throw bar location so the throw rod does not against the homasote.  If you didn't do this, still try the installation as I've suggested; but if the throw rod has too much drag you may find you have to get creative to get some space there.


If the turnout frog is powered you will need to wire it to the Tortoise to get correct polarity when the turnout is thrown.


I hope this helps; short of ripping up the track this is the best solution I am aware of.


Jim Brewer

Glenwood MD



From: "NW Modeling List" <nw-modeling-list at>
To: "NW Modeling List" <nw-modeling-list at>
Sent: Wednesday, February 10, 2016 4:40:52 PM
Subject: THE SIX P'S


Those of you who have served know what they are.


This is, though, a serious question.  In laying track I ignored the above p's.  As a result, all switches were laid without any consideration of how to operate them.  So....AFTER the fact, while I'm sure no one else has ever been so dumb, has anyone heard of a way to operate switches without ripping up a bunch of track and the switch itself?  I know Micro-Mark has some products that could help, but with the cost I would really like to get it right this time.


Oh, by the way, some of the switches are beneath bridges and pretty hard to get to, including the wye switch; the guilty party is just behind the two bridges.


IF anyone has experienced or heard rumors of other "not sharp tools in the shed" and how they fixed the problem, I would be really thankful.


PS - would you favor manual or powered, like The Tortise?  Can it be installed without ripping up track?


Thanks for any help.......



Ed Svitil
Norfolk & Western Railway



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