Mk3 Throw Index

 

 

 

 

The improved Mark 3 Turnout Throw

 

 

 

 

 

 

Time takes its toll, securing the toggle switch with a large dollop of epoxy adhesive seemed a good idea, but two years of hot and cold, rain and snow did the trick and the toggle switch is now a floater.

 

 

 

 

 

 

 

 

 

 

 

Time to come up with a longer lasting solution. It just so happens that the U-shaped cable clamps which are used to wire houses have the correct radius to fit over the round toggle switches or at least they are as close as it gets. Two screws to secure the clamp solved that problem and if necessary some minor adjustments are possible without breaking a bond. First problem solved.

 

To make adjustment of the throw more flexible, the straight wire was modified into a Z-shape

 

 

 

 

 

 

 

 

 

 

 

In order to increase the holding power of the turnout in the respective positions - the round toggle switches have a weaker spring than the rectangular types - an over-the-center spring was added. Bent from 1/32” piano wire it provides what’s required.

 

 

 

 

 

 

 

 

 

 

 

To prevent wear in the wooden tie a piece of brass tubing is used as a sleeve for that pivot point. The two additional holes in the ties are for the switch cover.

 

 

 

 

 

 

 

 

 

 

 

To provide the repeatability a small drilling jig was fabricated from styrene.

 

 

 

 

 

 

 

 

 

 

The cover to fit over the toggle switch required a slight modification. Generous amounts of silicone caulking will hold it in place and at the same time keep out the water.

 

 

 

 

 

 

 

 

 

 

 

Time will tell.