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Old December 1st 08, 10:22 AM posted to rec.aviation.homebuilt
Stealth Pilot[_2_]
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Default Pretensioning cables

On Sun, 30 Nov 2008 18:35:29 -0800 (PST), John
wrote:

On Nov 18, 12:33*pm, Gig 601Xl Builder
wrote:
Anyone have a good method for pretensioning cables. There has been some
issues of late with 601Xl control cables getting loose after the first
few flights.

I'm looking for info on ways to pretension 1/8" galvanized cables that
are tensioned between 22 and 40 lbs.


I have been working on a well known VlJ that recently declared
bankruptcy. It is the first aircraft that I have ever worked on that
discusses pretensioning cables. Basically they tension the cables to a
figure well above nominal. Then back off and retension to nominal.

John Dupre


The humble old Cherokee 140 has an interesting pretensioned control
run ...to the ailerons I think.
the cables run from the surfaces via the usual pulleys then terminate
in sections that look for all the world like bicycle chain. these are
run up past two sprockets which are bolted together. the positions
that the sprockets are in when bolted determine the amount of cable
tension in the outer runs. past the sprockets the run to the yolk is
actually almost untensioned completely.
this allows the cables to, in effect, be used in a pretensioned state
while the yolk controls feel light and friction free.

it is a damn cunning arrangement that works superbly.
Stealth Pilot