March, Bill Eberhard gave us a demonstration of the techniques of soldering.
Many times in our hobby,
it is necessary to join two pieces of metal or one reason or another.
Billís example was the fairly
common one of constructing a landing gear. When we find that the gear is
not delivered in its final shape, (curses) then it becomes necessary to
take the work by the horns and set it to the torch.
For large items such as
struts where a great deal of abuse is expected, the metal area can be quite
large. An ordinary iron simply canít get the work hot enough.
Bill then tightly wrapped
ordinary small gauge copper wire tightly around the pieces he planned to
join. This served to hold them as well as conduct heat to the area. The
most important thing was to make sure that the flux thoroughly reached
the entire joint.
Flux is an acid which prepares
the surface of the work so that the solder can flow easily. Acid flux is
used on metals, whereas rosin flux is used whenever electrical circuits
are involved. Two dissimilar metals in an acid is known as a battery.
Bill used a small torch
in order to apply enough heat to the work. the rule for successful soldering
is that the work must melt the solder, not the iron.
After soldering the wheel
strut, Bill passed the finished work around. It looked great. Bill next
took on the common but necessary task of soldering clevises to control
wires. Here the iron was sufficient, but he emphasized the
importance of flux in ensuring a good solid
Bill mentioned one of his
pet peeves, giant Z-bends in control rods. Many a crash has been traced
to this practice.
When setting up the control
horns, the correct method is to maintain a straight line all the way from
the horn location through the fuselage to the servo.
A dramatic demonstration
using a piece of wire with a z-bend and a straight piece of wire quickly
made the point. Bill took a hammer and pounded the wire into a block of
wood. The straight wire went through the wood but no matter how hard you
hit the bent wire it never penetrated.
This was a very informative
presentation and people learned to appreciate the finer points of the soldering
Finding your way in days gone by
In January we were pleased to have Hugh Spears describe how navigation
was done in the days of bolts and bailing wire.
After the war he ferried
planes from the manufacturer to the customer. This was before the days
of Nav Aids such as DME (Distance Measurement Equipment) or Tacan, so finding
the course involved the tried and true methods of Dead- reckoning, basically,
a compass and a map.
These techniques are still
used by pilots of small aircraft at country airports.
Much of the advance in navigational
aids was tied to the weight of the
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