Point actuators.
Again, we reviewed Geoff's work on the revised 'all-in-one' actuator and agreed that it was the right solution. That said, we turned into a production line again and modified the rest of the units.
Laurence drilled the additional holes for the new horn. We decided on a hole on each side, just in case we wanted to switch the position. He also fitted the extra micro-switches required to change the polarity of the frogs.
Geoff turned up spacers to lift the new horns off the base plates. His prototype has a rod spacer, but this proved difficult to tighten, so the new ones were made of hex bar. The turned top fitted into the base of the horn.
Stephen made up the wire connectors, trimmed the horns and performed the final assembly.
Once the first one was ready, Geoff fitted it alongside his first unit, but this time wired the frog switch as well. The fitting became a group-effort as we developed a method of aligning and fixing it in place. The hole in the baseboard needed to be countersunk slightly to give better clearance for the horn-end, but generally, fitting was simple, as the actuator wire could be easily 'tweaked'.
We were so engrossed with our tasks, that we overran lunchtime by 40 minutes!
As reported previously, Geoff had tested the new unit on a DC supply and finding it no different to half-wave AC, had purchased a low voltage DC supply. We now went over the options for operating the actuators. The existing solenoids had stud contacts on the panel (i.e. two supply wires in the loom) and a common return from each board. Most points were operated singly, so the same two loom wires could be used to feed the output from a DPDT switch, with a cross-over. Where two points were currently controlled together, Geoff suggested we operate them in sequence, like a real railway. This would either require additional wires from the extra switches, or a cunning plan to stagger them operating. G&S both agreed that the latter would be a great challenge to design, with the ability to fall back on the extra wire option if we failed. Watch this space!
With the old studs being replaced with rotary switches (our first choice and what we had a lot of!), we looked to the control panel itself. We always knew it would have to be replaced at some time, as the layout requirements were likely to change. Stephen had donated an old panel, which will need a new top, but was otherwise quite suitable.
The old panel had two power supplies. An AC supply for the ECM speed controller and a DC supply for the points. The latter was needed as the capacitor charging load would have interfered with the loco control. After some tests on the new servo motors, Geoff declared that this would no longer be a problem, so a single AC supply would suffice. As Geoff had already fitted a bridge rectifier for the feed to the DC power supply, only one, large AC supply was now required.
