To me, mapping out the wiring of a model is extremely important. This should be done while the model is in the planning phase. To keep things easy to follow and future reference, a drawing or schematic should be made and kept. No two models are the same.
To see different ways to wire a trolley model look at chapter "Electrical Control of Model Traction" in the "Model Traction Handbook for Model Railroads" published by Carstens. Several methods of control and wiring are presented.
If you have both trucks insulated for 2-rail, it's easy to wire up a model to run on both trolley wire and 2-rail. In the following drawing the term at the bottom "Positive = RED" should be "RED Wire or Terminal on the Power Supply". The main draw back is having good contact between the trolley pole and the trolley hook.
The main "positive", advantage of pole reverse wiring is, as long as the power supply is set to forward, the model will go forward. This is exactly like the prototype!
POWER TRUCKS
A photo of of the dual power trucks made by the Q-Car Co. appears in the prior post. Dual power was chosen due to the weight of the model itself plus the unknown weight of the trail car it will pull.
If you have worked with power trucks in the past you are aware of the running characteristics of the truck in one direction vs. the other direction. In one direction the thrust is against the end of the gear box while running in the other direction the thrust is against the nose motor bearing. Often the sound of the truck running plus its speed are not the same.
Therefore if 2 power trucks are to be installed in a model it is best to mount both in the same direction. Of course there are exceptions. But, be cautious and don't ruin a power truck.
The completed model is being held in a Bowser foam cradle. Note both of the gear boxes face the same direction. The underbody detail work came with the model. All I added or changed is the electrical wiring and the guts of the trucks.
Both of the sets of sideframes had been altered to match the prototype. This also meant the the sideframes were able to clear the steps. If you are sending Q-Car or Current Line Models sideframes which require special consideration such as direction of the gear box or with regard to direction of travel, tell them about your requirements. The trucks will built accordingly.
This shows the alteration to the end of the sideframe plus the addition of PSC brake rigging to the truck.
You may have noticed the prototype AE&C 311 to 315 series of cars had 8440 sideframes which have an 84" (7') wheelbase. I'm using 7830 sideframes which have a 78" (6'6") wheelbase. I do this for the clearance around the steps. O scale trucks are oversize to start out with. In O scale the track gauge is 5'. Truck sideframes are wider and often made with a soft cast metal. The PSC lost wax brass sideframe looks just as good if not better than the 8440 sideframes.
What turned out to be the most interesting part of changing from the Multi-Units to Q-Car powered trucks was, once the body bolster and brass floor were drilled out for clearance of the 2-56 mounting screws, the new trucks could be just installed as they are. There was no need to make the body bolster thinner. Or, no washers were required between the body bolster or truck bolster to raise up the body.
Here the body is in the foam holder. The interior is in place. The front truck has been installed and the Nyloc nut supplied by Q-Car attached . I prefer to place a spring between the nut and the floor. This keeps the truck tight against the body.
Also, in the photo can be seen the 2 brass rods to hold the roof to the body. They are used to bring trolley current from the roof to the trucks and vice versa. The rear (right in the photo) rod with a piece of insulating shrinkable tubing over it is being use for this purpose.
The washers, nuts, and pieces of plastic in the lower part of the foam are for bolting the roof on to the body. The set on the left hand side are for the rear brass stud. The pieces of styrene are being used to insulate the stud and connection from the underside of the brass body.
The front brass stud does not need insulation protection. A washer and nut are all that are needed.
This is the rear body bolster. The red wire is attached to a small, hand made 0.005" brass connector to fit over the rear brass stud from the roof with the trolley circuit. The red wire goes into the car body to the Dallee adjustable constant voltage for the lighting. It also goes to the power trucks. I like to use Miniatronics 2 pin micro-mini connectors. You can make your own connectors.
Miniatronics states their connectors are not to be used to power rolling stock. I use both wires soldered together to carry the trolley voltage to the power trucks. Using connectors instead of soldering the wires together make it easier to service the power truck in the future. A Miniatronics 2-pin connector for the rear power truck can be seen to the left in the photo.
One modeler I know connects wiring in the model with small power blocks made of wood or styrene and screws. He avoids soldering all wires together.
A gray wire attached to a larger, hand made 0.005" brass connector is to be used to pick-up the rail ground and bring it to the Dallee board. Each motor in a power truck is grounded to the truck frame.
The rear power truck is being test fitted into the car. The brass connector to pick-up the ground can be seen. There is still some dirt to be cleaned up from the power truck.
For final assembly the roof is added last. A nut driver has to be fitted in between the end of the frame of each truck to attach the nuts to each brass stud from the roof.
Here is the finished model. The destination/train class signs on the dash need to be lettered.
Next comes the companion car, the Florence, for the 314.
Cheers,
Ed
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