Classic Europa, Manual - Issue 1, page 13-3 to 13-4 Flying Controls
Funny how you learn only after the first attempt........
This section is the early assembly and installation of controls - into
the cockpit module, just after applying the brake master cylinder. This
embodies the aileron torque tube from front ofthe seat to the back. (The
pitch rod runs inside this tube).
Joystick fork - CS02
Bearing bush - CS03
Tufnol plate - CS04
Torque tube - CS05
The task is to slide the bottom (of the joystick) fork CS02 onto a
two-inch-long 'bearing' tube CS03 (facing onto the Tufnol block CS04),
into which a concentric torque tube CS05 fits. These three concentric
fittings are fixed together by a combination of Redux 420 coating and
six pop rivets. The manual directs one to coat the applicable surfaces,
assemble and let cure. Then the predrilled holes in the outer ring are
drilled through the other two when cured. The perceived problem was that
with the 'play' evident (see below), the three would cure out of common
eccentricity and later binding might accrue.
Now, I may be confusing this with some difficulties mentioned in stiff
ailerons at a later stage, but it occurred to me that if the three tubes
were properly concentric (there is a lot of 'play'between them when raw)
before they were joined then they would cure concentric. I "miked" a
number of materials to see what could layer the tubes to reduce 'play'
and finally settled on my printer paper which proved to be a consistent
4 mils (4/1000 in.) in thickness and which reduced the play almost
entirely without being impossible to insert. One might even try 5 mils
for fit. Once installed between the three tubes, the play was almost
mperceptible.
I then disassembled and drilled the outer tube to spec with the 3.3mm
drill, then re-assembled all three with the paper in between them and
2mm film between bearing faces and Tufnol bearing, positioned each
carefully and redrilled one hole. I filed a halfinch-long #6x32 machine
screw to reduce it to 3.3mm and fitted it into the first hole. Now the
three were fixed and concentric, so drilled the other five holes -
filling each with a filed #6 screw as I went.
I then returned to the manual and epoxied each per instructions and
reassembled, keeping the holes aligned as before. The holes have to be
'cleaned' of wiped epoxy and I inserted softwood dowelling (1/8in.) for
alignment. After curing I redrilled the six holes, comforted in the
thought that I had done all I could to align the three parts properly.
'Cept I didn't do this with the first @#$%
& set!
CAUTION:
I have not mentioned the epoxy precautions, chamfering the Tufnol, nor
the bearing grease inherent in the process, so read ahead before
tackling! Hope this is of use. 'Flamers' invited.
Happy Landings
Ferg #A064
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