DCC Impulses Column - 5
the car. Install the ring terminal (or make one by looping your
pick-up wire around itself to make a ring and tin it in place).
Then add a second nut to hold the terminal in place. Use a
pair of wrenches or pliers to jam the nuts against each other
making a tight electrical connection, while the truck is free to
pivot through the floor. That’s why they are called jam nuts.
Then install the wheel sets, making sure that the insulators are
on the same side (bottom in the photo 7). When mounting
the trucks on the car, make sure each truck has the insulators
on the same side and they are different between the trucks.
Otherwise, there will be a rail-to-rail short.
Conductive lubrication, such as Never-Stall
, should be
applied to the sliding surfaces between the contact strip and
7: top and bottom view of truck & wiper assembly
attached to a mock-up of floor (using Kadee red
washers to simulate the pivot surface) with jam
nuts and ring contact – note wipers have been trimed
since figure 6.
7
the axle and between the contact strip and the mounting nut-
bolt-washer combination.
Lights
If I’m building my own lighting kit into a car, I prefer LEDs. They
may be surface mount (SMD) LEDs or 3 mm or even 5 mm,
depending upon the space available. Enclosed LEDs, such as 3
mm or 5 mm devices, frequently focus the light in a column so
I tend to use SMD units whenever possible, as they frequently
provide a broader area of illumination.
The large scale car that I’ve been featuring throughout this
column (8) used two strips that had three SMD LEDs and a
dropping resistor designed for 12 Volts. I bought them at an
electronic surplus store online. They came with blue-white
colored LEDs. While these make a good “fluorescent” look, they
8: Lighted passenger car from figure 1 with the roof
off, showing LED packages installed
8
MRH-Sep 2013
