Model Railroader – October 2019

October 2019 41

The freight car trucks were an inter-
esting challenge. Commercial brass
trucks were available, but they tended to
be expensive. I laser cut parts to make
my own trucks using commercial wheel
sets. Some of these trucks also have a
working hand-brake mechanism.

Photo etching

To simplify working hand-brake
construction, I used photo-etched metal
parts ❽ on page 43. The photo-etching,
or photo-chemical-machining, process
produces precision metal parts by selec-
tively dissolving metal into solution. My
photo-etching projects aren’t done in-
house. Instead, I use a professional etch-
ing firm in Massachusetts. I provide the
artwork, which the etching firm converts
to a photo tool to make the parts that
they then send to me.
I had a learning curve to understand
designing etched-metal parts, especially
those that fold to create 3-D objects.
There’s also a limit on how fine parts can
be made, generally 1.5 times the etch
material thickness.
I used photo-etched parts, brass
chain, and phosphor bronze wire to
make the brakes operational on some
cars. The operator turns the brake wheel
on the roof and the car’s brakes are
applied. This task was simplified by the
fact that instead of airbrakes, cars in this
era had only a hand brake on one truck.
I’ve also used the photo-etching
process to make other parts, including
my switch stands and freight car and

❹ Freight car construction. This unfinished freight car model shows the typical

method of construction Bernard uses for his laser-cut freight cars. He cuts the

frame members from a single wood sheet with interlocking tabs and slots to

help simplify the construction process.

❺ Passenger car construction. Bernard used his laser cutter to make the basic

core of this O scale passenger car out of^1 ⁄ 8 " acrylic. The coach’s interior details,

such as the seats and trim, also employ laser-cut parts.

❻ Finished model. Here’s the finished passenger car in service on the Aquia Line. Bernard scratchbuilt the handrails from
phosphor-bronze wire. The trucks are from SMR Trains.