Throwing switches

[lionelsoni]

A choke cable has the advantage over a bicycle brake cable and a clutch cable that it stays wherever you put it. Simply bending the center wire into a Z shape at the switch is an easy way to put a little springiness into the motion, for overtravel.

[daan]

Good idea roy! I've used the double cable as well on a former layout in h0, but the cable I used was not strong enough to hold for a long time. You need guiding wheels on every place where the route of the cable changes direction, and a bowdencable doesn't need that.
The spring is something I havn't thought about. (Märklin didn't think of it either, I copied their system)
Another way to throw switches is with small pistons and an airtube, or a small compressor and small pistons to throw the switches. The pistons can easily be homemade with some cupper tubing and a leather piston, but I doubt if this technique works relyable on the long term (also a Märklin-thing from prewar)

[FJ and G]

Great point, Roy, I've heard of using springs but your explanation is esp. good and I have yet to try the technique.

[wrmcclellan]

Daan,

As you noted, this is an old model railroading technique. You can add springs to achieve some ability to run through a switch.


Control end<>------------------[switch-points]------/\/\/\/\/\-------o cable secured this end

spring = /\/\/\/\/
So normal operation has the spring in tension with the points set for the main route. If a train approaches from the diverging route the spring allows the train to run through (as long as the spring is not too strong),

If you use a flexible cable loop control (pulley at switch end and rocking lever at control end), you can use 2 springs and allow both routes to be approached regardless of setting of points.

I
I__________/\/\/\/\/\/\--------[switch-points]___/\/\/\/\/\/\____
I_______________________________________________I pulley end
I
I
^
lever end

Regards,
Roy

[FJ and G]

Nice, Daan,

I've used clutch cables the same way

[daan]

Just a small idea I used on my layout to convert handoperated switches into switches which can be operated at a distance.
First go to a bike shop where they sell mountainbikes and stuff. You need the brakecables which are sold seperately. In our pushbike covered country those sell at 5 bucks a pair.
Make a small steel wire to the throwbar on your switch and solder one end of the cable to it.

Like in this picture. Drill a hole in your layoutstructure, but drill it angular to avoid knicks in the cable. It should run smoothly without sharp bends.
Fix a bracket or something to hold the outer cable and be sure that the inner cable runs free.
On the other end you can make a lever to throw the switch. If the cable is too short, simply solder another cable to the end of the first and make 2 other brackets to fix the outer cables to the base.
Guide the cables under your layout with tiewraps or small clamps.

It's cheap and works great if installed properly, but the train can't open a switch by driving from the other side when a switch is set in the other direction and it's not suitable for a big layout with central controls, since the cable's friction will get too big to operate securely.