reassurance that I would be making fittings that are
safe to fly with. Not even coming close to making
good-looking soldered fittings, I made up several 1-foot
assemblies of galvanized 1/16-, 3/32-, and 1/8-inch
cable to pull test. Having access to calibrated tensile pull
equipment made this phase more fun.
As a baseline, I made matching assemblies with the
standard “nico” process. I pulled and documented all
failures. I was somewhat shocked, and pleased, that
every one of my amateur-looking assemblies failed at
the cable, not the wire-wrapped and soldered fitting…
and, as an unexpected bonus, at or above the rated cable
strength. At this point the battle was won and it was a
matter of technique and practice to make some fittings
that I would be proud to put on my Air Camper.
I can’t retrieve it at this time, but somewhere I saw
specs for these wrappings. Important to the design of
the wrap is a “window” or single 360-degree wrap that
spans 3/16 to 1/4 inch every 1/2 to 5/8 inch (twice)
during the wrap. This window allows the inspection of
the fitting for slippage or impending failure. Seeing the
solder “cracked” in this area is an indicator of slippage.
Let’s Make Some Fittings
Here are some basics that are relevant to cables. First, use
a cold chisel and an anvil (any heavy soft-steel block will
work) to cut the cables. The chisel should be sharpened to
a fairly blunt angle (maybe 60 degrees) but have a sharp
edge. Using the cold chisel is fast and clean. Make your
initial cut several inches longer than anticipated. You will
want to make all final cuts to length on an angle (we will
talk more about this later). I use the angle of the cable
twist itself and just lay the chisel on the cable, letting
the twist set the angle for me. One smart smack with
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