Cheers,
If the title grabs your attention, you remember text on "tightened"
pitch controls, or you have not yet placed your cockpit module in the
'canoe' - this may be for you..
There were a number of messages concerning the pitch losing its
'loose' quality after a while. I am ready to install the cockpit (an XS in a
Classic Mk.1) and have the module standing on its nose where I can install
further fuel fittings. In the process, I noticed that the aileron travel was
markedly tighter than I remembered it, and so applied some of that "Harrison
juice" ( Brasso) to the four Tufnol bearing surfaces and ran my stick-shaker
(a slow 12Vdc Motor driving a stud through a seven-inch circle, and inserted
into the stick tops) to exercise the Brasso. Lo or behol', the bank control
path loosened up magically, but the pitch channel remained frictionful.
I had philosophised that it was the "canoe" imposing its shape upon
the cockpit which diverted the control paths enough to force the four
tufnols out of common plane, and so had sworn to use some bright builder's
plan to insert the cockpit into the canoe with the former carrying "yokes"
(oaken bucket style) which are then winched down into the canoe while the
latter is held perfectly horizontal - on the grounds that the canoe would
then peripherally take on the cockpit shape rather than the other way around
(all variables being monitorred of course).
Then entered a visitor with swift mechanical mind. He soon noted the
relative friction in the pitch mode. We were fiddling with the module when
the pitch I was exercising suddenly eased up! I marvelled at this till he
said "I just pulled this bracket outboard", and showed me the top of CS09!
Remember the end brackets on the pitch torque tube and their "cuddle
plates"?
Egad! The simplest pressure outward on the peak of CS09 relieved
the pitch system instantly. Then it dawned - the slightest pressure on the
shape of the cockpit bottom cheeks would add pressure inward to the
CS09............
That's where I think our common complaint originates - forcing
the CS09s inward at the bearing toughens the pitch control run a great deal.
So, I am going to see if it can't fix a pry between these CS09s
such that they are held open only enough to ensure relieved pitch controls
while the 420 hardens in the canoe. Naturally, sweet logic dictates guarding
against any excess force which might cause excessive wear.
Any other suggestions greatfully received. Flamers even.
Ferg A064
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