USAT F3 build - remote couplers and lighting
I'm working on customizing an F3 while I'm waiting for the snow to melt so I can set up some track. I've installed a Airwire Drop-in, Phoenix P8, and battery, and have tapped the data line to the P8 to listen for function packets with an Arduino Pro Mini. I'll be using the Arduino to drive remote couplers and customize the lighting. The first task was remote couplers.
I found that the proper height for the coupler lands the draft gear box 1/2" below the bottom of the deck. At the front, I was able to squeeze the Kadee 11220 in between the front truck and the pilot, and cut a slot up under the little bumper under the nose door to get it to the proper height. I made an adapter plate from 1/8" aluminum in order to use the holes from the original pedestal. The plate is on 3/16" spacers, and the coupler is on another set of 3/16" spacers, making up the total 1/2". At 3/16" below the deck, the plate is clear of the trucks when they swing, and high enough (close enough to the deck) to stay out of the way of the curved pilot casting. The plate is tapped for 4-40 machine screws to accept the coupler.
The rear coupler was another story. There is not enough room between the rear truck and the back of the unit to fit the 11220 without the coupler sticking way out past the bellows. This wouldn't look right if I attached another engine or coaches to it. I went around and around, and finally decided to use an 831 gear box and mount a small servo inside the engine to pull the chain to open it. I cut a slot in the deck for the servo horn to stick through. The gear box is mounted as far aft as possible, and secured with two #6 machine screws with nuts, spaced 1/2" from the deck with nylon spacers. One had to be whittled a bit to accommodate the shell of the engine.
When I make some progress on the lighting, I'll post here. I essentially want independent control of the headlight/number boards and classification lights. I'll be changing the classification lights to white, and converting everything to LED.