I agree with Kingsley that the alignment of the bolts needs checking.
Misalignment often shows itself as varying aileron play depending on the
amount of aileron deflection.
I have cut out a small part of the wing fairing on the underside, just aft
of the spar, about four inches long. This gives you a good view of the
offending bolts, particularly if you fit the wing with the bellcranks
removed, and gives just enough room to follow the "Kingsley procedure" for
re aligning them, using a pair of long nosed pliers to slide the tubing
across. You can stick the cut out back in place with white silicon
caulking/RTV after adding a couple of small flanges to it. No one will ever
know you been there!
Don't forget to slide the tubing off the bolts before trying to take the
wings off- been there, done that!
Regards
Brian Davies
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Kingsley Hurst
Sent: 22 February 2011 13:06
Subject: Re: Europa-List: Aileron play
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.
* Applied just enough Redux to the head end of the shank of the bolt
so that after cure, it would hold the bolt firmly.
* Worked the bolt and Redux into the slightly enlarged hole until
fully engaged.
* Slid the sleeve over the bolt just inserted.
* Rigged the wing.
* Slid the sleeve along until fully over the shorter bolt or at least
even over both bolts.
* Ensured the bolt in the spar was still fully engaged using long nose
pliers on the still visible part of the shank
* Tip toed away quietly so that it wouldn't see me going and
inexplicably move !!
* Returned after allowing time for Redux to cure i.e. next day.
* Slid sleeve back over the bolt in the spar and removed the wing
again.
* 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" < <mailto:frans@privatepilots.nl>
frans@privatepilots.nl>
Sent: Monday, February 21, 2011 11:23 PM
Subject: Europa-List: Aileron play
<mailto:frans@privatepilots.nl> 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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