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Turnout linkages have always been a problem for me. I don't like the cost of slow action switch machines or the size of commercial ground throws so I've tried to build mechanical linkages with everything I could think of. I also want working semaphores on my turnouts. The one I'm showing you here currently has the most promise.

Figs  1, 2, 3, 4, 5 and 6



    This is a Studio Max plan of the turnout linkage. I've borrowed the basics of a Rix products turnout linkage design and adapted it more my uses. The line traveling off to the opposite side from the spring is the run to the fascia board.  Figure 5 above shows the track side and how the semaphore works.

Building the

Turnout Linkage

 This is the Cad drawing of the acrylic bracket and brass pivot bar. I'm not going to get to much into the dimensions of everything as, if you build these, the factors that effect them are numerous, thickness of road bed, length of return spring, travel of slide switch and if you plan to include semaphores. The tie to the fascia is planned to be string through eyes ( from hook and eye catches ) connected to a standard light switch but if this doesn't work I'll resort to choke cable style activators and or direct rigid rods where possible. More on this when I figure it all out, for now with this linkage I can throw the turnout by reaching under the layout and moving the bottom of the pivot bar back and forth. 

    Figure 16 show the trip wire for the semaphore and 17 shows it in the jig ready to be soldered. Figs 18 and 19 show the two possible configurations depending on how the bracket is mounted under the road bed. 20 and 21 show the completed assembly. The two acrylic blocks I glue on at either end of the travel of the pivot bar are taking the load of the switch from the spring or the human throwing the switch.

    Figures 1 and 2 show the built acrylic bracket and 3 shows the SPST switch I use. This switch also does power routing for the frog. It has a travel of 0.1" and by installing it twice the distance from the pivot point as the tie I get 0.05" of movement at the turnout. Figures 4, 5 and 6 show heat sinking the 1/2" common nails into the acrylic to mount the switch. This keeps the acrylic from cracking if you where to hammer the nail in.

    Figure 7 shows the 1" long .040" spring steel wire that I solder onto the end of the .040 by.250 by 3" brass pivot bar ( figures 8 and 9 ). The brass is a standard K&S item at your hobby shop. Figure 10 shows the jig I made to hold everything in alignment while I solder and figures 11, 12, 13, 14 and 15 show soldering up.

Turnout Linkage
V Fig 1