After many years without one, I finally purchased my first double slip.
Route selection can be complicated because there are two throwbars which must be set to properly align the point rails.
I have designated the four tracks as A, B, C, D to illustrate the routes, as shown in the following illustration:
There are 8 possible routes on a double slip: A to B, B to A, C to D, D to C, A to D, D to A, B to C, C to B. Of course, some routes are not possible: A to C, C to A, B to D, and D to B.
In setting up my control panel for the double slip, I marked the four tracks with their alphabetic designation and added a red or green circle to aid in the visual identification of the track. The squares below the double slip symbol in the illustration that follows indicate DPDT toggle switches. The circles above the double slip symbol in the illustration indicate bi-color (green/red) LED's that will illuminate as the DPDT toggle switch is thrown.
If the toggle switch on the left is thrown up to move the left throwbar up, the LED will illuminate green. The LED will illuminate red if the toggle switch on the left is thrown down to move the left throwbar down.
If the toggle switch on the right is thrown up to move the right throwbar up, the LED will illuminate red. The LED will illuminate green if the toggle switch on the right is thrown down to move the right throwbar down.
The illustration that follows shows the 8 routes, the position of the toggle switches as up or down, and the resulting color of the corresponding LED.
It should be noted that proper routing will always result in matching LED colors. If the colors don't match, the throwbars are not set properly and a derailment wil result.
Visually, the easiest and quickest way to throw the toggle switches is to identify the destination track by its color. For example, if the engine is on Track B and is headed for Track A, both LED's should be illuminated green, the color of Track A, the destination track. So, the left throwbar should be up and the right throwbar should be down.
It is interesting to note that the straight through routes (A to B and B to A, C to D and D to C) are always set the same way but the divergent routes (A to D and D to A, B to C and C to B) are always set the opposite way. It should also be noted that the postion of the two throwbars are always the opposite (one up and one down) but never the same (both up or both down).
Hope this helps.
Rich
