John,
Once you sent a basic pic of what you meant about the hinge, I followed what you were talking about.
I have done my DS with just the 2 tiebars (1 each end)
I have used steel track pins that I filed the paint off of so that they could be soldered rather than brass pins as I was worried the brass wouldn't be long lasting in the longer term.
I also use Copperclad for the tiebars. (Using copperclad you need to remember to cut the copper on the underneath as well you obviously realise how I know that )
To space the gap of the blades I do 1 pair and then the other using the same thickness item (offcut of copperclad 1.06) as the spacer. So what you have is one blade against the rail and the other corresponding blade has the spacer of copperclad. I then use another piece of copperclad as the second space required for the other side.
Hope this all makes sense!
Given I am a electrical heathen, up until now I have used slide switches.
This time around I will be trying a method of leavers from a central point and rods and cranks as I saw used on Youtube.
The guy also used micro switches to control the power to the track.
hope this is of help.
Khris