Hello Frans,
> Other ideas are welcome of course.
At the risk of disagreeing with others and saying something stupid
because it is now late at night and I'm tired, I would suggest that your
problem is that the two bolts on which the quick connect bellcranks
pivot are not exactly aligned. For the bellcranks to operate correctly,
they must pivot on a common axis so that they both describe exactly the
same arcs when operating. Tests I did proved that only a very slight
misalignment has quite an effect on the gap between the two bellcranks.
If the bolts are not exactly aligned, as the bellcranks swing in
different arcs, they either become tight or loose. When they become
tight, the bolts, what is supporting the bolts or both, flex to absorb
the load induced by the two bellcranks fighting each other.
If the bolts ARE correctly aligned, they act like a single bolt with a
gap in the middle so when fitting the tufnol strips, there is no need to
do so on the aircraft. This job can be done in a vice with a long bolt
and the bellcranks both mounted to it in their correct orientation.
This makes the job very simple and removal of any excess Redux is a
breeze.
The tricky part is getting the two bolts correctly aligned in the first
place and it is a long while since I did it so I hope I can remember
correctly. I enlarged the hole in the spar to allow the spar mounted
bolt to be a little sloppy. I thiink I then somewhat rebated the hole
on the bellcrank side of the spar making it similar to what was done to
the spar on the head end of the bolt. This rebate was to allow
permanently potting the bolt later to be made easy.
I then made up a neatly fitting sleeve as long as possible so that it
could be slid from the longer bolt over the shorter one (when the wing
was rigged) but when slid back again over the longer bolt, it revealed
the gap between the two bolts to allow disassembly.
The rest of the job went like this.
a.. Applied just enough Redux to the head end of the shank of the bolt
so that after cure, it would hold the bolt firmly.
b.. Worked the bolt and Redux into the slightly enlarged hole until
fully engaged.
c.. Slid the sleeve over the bolt just inserted.
d.. Rigged the wing.
e.. Slid the sleeve along until fully over the shorter bolt or at
least even over both bolts.
f.. Ensured the bolt in the spar was still fully engaged using long
nose pliers on the still visible part of the shank
g.. Tip toed away quietly so that it wouldn't see me going and
inexplicably move !!
h.. Returned after allowing time for Redux to cure i.e. next day.
i.. Slid sleeve back over the bolt in the spar and removed the wing
again.
j.. Finished potting the bolt on both sides of the spar with Redux.
Job done.
I'm well aware you now have wing fairings to deal with so short of
cutting a hole in them to allow enough access, I can't offer any other
solution. You can choose from some of the already suggested methods but
IMHO, I really don't think they will fix the PROBLEM. The situation may
be improved but unless I'm barking up the wrong tree, I think you will
find the trouble reoccurring.
Best regards and good luck
Kingsley
----- Original Message -----
From: "Frans Veldman" <frans@privatepilots.nl>
Sent: Monday, February 21, 2011 11:23 PM
Subject: Europa-List: Aileron play
<frans@privatepilots.nl>
>
> When we built the PH-DIY the aileron system was tight. But after 91
> hours of flying and repeated (de)rigging, everything settled in, and
> some play developed at the quick connect system.
> There is no play within the wing itself, nor in the airplane, but it
> sounds like it really is at the mating surface of the two quick
connect
> surfaces and the surface shows some wear.
> Does this sound normal?
> With the wing root fairing in place it is a bit awkward to make
> measurements and get a visual confirmation.
> My plan is to add another tufnol sheet on the bellcrank surface to see
> if that solves the problem. (There is no play on the bearings).
> Other ideas are welcome of course.
>
> Frans
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