A new fiddle yard for Hexworthy part 2 - making it work

Almost a month after I started the new fiddle yard for Hexworthy I got a free Saturday to get it working. Actually, it isn't entirely new.

The deck seen here is from the old fiddle yard, although it took some thinking to work out how I could use it with the same geometry with the pivot moved about 8" towards the front of the layout. The previous yard had tapered towards the wall, this one has to slew away from it to clear the pillar. The pivot had to move right to the edge of the board and as you can see, it's a tight fit to get the full movement. 

However, to allow the movement across all tracks and run into the same entry track to the layout without a sharp S-bend in the transition I found the front siding of the sector plate had to be repositioned. I managed to lift the track and its PCB end sleeper with a knife blade (having been glued with Bostick), and prise the brass pin out of its hole. A new hole was drilled about 10mm closer to the next track, the pin pushed in, and the track glued down with a slight curve ensuring the rails were in line with the pivot where they met the edge. 

Under the board I managed to refit the latching mechanism, after a bit of thinking. Here's how it works:

• In the curved slot the white arc is the lip under the sector plate, with the three brass pins protruding (the right hand one having moved holes)
• The wooden arm is pivoted at the bolt on the left, and on the right carries the aluminium latch, which has a gently curved edge with a notch at its centre. The aluminium is connected to the red wire so it carries power to the pin it touches. 
• On the arm the white foamboard piece presses on the soap-dispenser spring attached to the block of wood, the foamboard allows some adjustment of tension in case ever needed
• The plastic "T" shaped piece is a leftover from the fitting of our kitchen. I have no idea what it was intended to do, but it proved useful here as a stop to limit travel of the arm. A block of wood could do the same, although currently the spring tension is such that the arm stops just short. 

From above the sprung arm and its aluminium latch can just be seen, with the notch central to the track. Of course, I positioned the arm/latch first, then positioned the track to align to the sector plate tracks when latched. The transition track is on a piece of foamboard (both recovered and cut down from the previous fiddle yard), which allowed the track-bed height to be adjusted, in fact a 10-thou piece of plasticard was inserted at the sector plate end. 

Power connection to the layout is via an audio RCA cable. Previously I'd put sockets on both boards and used a "jumper" cable, but here I figured a tethered cable was less likely to get lost, so a few inches was cut from the end of an old cable. The grey block of wood is just there to ensure nothing rolls off the front track when pulled fully forward. Previously I'd fitted a lever to allow the latch to be disengaged to move the sector plate, experience found this wasn't really necessary so here I didn't bother, there's a little resistance to overcome but the plate can simply be pushed between positions. 

The good news is it all seems to work and fit. The new catches allow the fiddle yard to be attached and detached much more easily, and the self-latching sector plate works as well as before after its transplant. At some point it will get a coat of grey paint to match the layout. However, a bigger job is to rebuild the "exhibition" fiddle yard to use the catch connections, and to make it more reliable.