<<Any questions??!!>>
How tight did you tighten the nut, given that the instructions don't
call for it to be tightened?
Duncan McF.
----- Original Message -----
From: David.Corbett
To: Europa Forum
Sent: Friday, August 10, 2007 5:43 PM
Subject: Europa-List: Mod 74 progress part 2
I have been asked by Anthony van Eldik how I got on with pip pin
alignment; here is the answer.
The new bolts were easy to screw in by hand, using the pip pins to
give a little leverage; having screwed them in to the measurements I had
taken, we offered up the wings. The port wing required half a turn
adjustment, the starboard was correct, so we took the wings out again,
and then unscrewed the bolts, counting the turns - 21 for one, 20.5 for
the other. We then cleaned the threads, both of the new bolts and within
the bonded-in plates, to remove old Loctite. We then screwed the new
bolts in for 10 turns, applied Loctite to the remaining 10 turns still
exposed, and screwed in to the agreed position. We then refitted the
wings, and (because I was away the following day), left the Loctite to
set for 36 hours; that was Tuesday.
On Thursday morning I made the flox fillet; I was very concerned that,
if I used the Nyloc nut to position the washer such that it flattened
the flox, it might cause the new bolts to break away from the Loctite,
thereby ruining all the setting up; I therefore obtained 2 nuts without
Nyloc heads, and screwed them, with grease inside, up against the
washers - finger tight was enough to flatten the washer.
On Thursday evening we re-fitted the wings, fitted the Nyloc nuts, and
tightened them up with a standard ratchet; we then removed the wings
again ready for the lay-ups.
That all sounds simple; however, we had very great difficulty last
night getting the port pip pin in - it is definitely now a 2 man job,
because the wing needs to be tweaked forward (as the Mod instructions
said might happen), and quite a bit of pressure applied to the pin
itself, both to get it in and to get it out again. Before starting this,
and in anticipation of a possible problem, I got the pip pin rings
welded so that they would not just pull open under strong pressure. The
starboard pip pin now goes in more easily than before - and it was never
difficult (neither of them were).
Today I have inserted the foam plugs, and laid up the 5 layers of BID,
as instructed - and the job is signed off by my Inspector, although all
the filling is still to be started - and as there was well over 2 mm
filler ground away over the root of the wing, filling and sanding down
will have to be done in 2 or 3 stages.
On Tuesday, whilst getting the bolts correctly set up, we did damage
the head of one pip pin (where the ring goes through), and John Wheeler
at the factory tells me that they have no spare pip pins in stock - so
be careful!
In summary, I asses that because of the need to let 4 stages cure
before moving on to the next step (before getting to the filling and
finishing), Mod 74 cannot realistically be done in less than a week -
and I have the hangar space and all the tools and materials, and have
been able to work on a pair of wings at the same time. You need two
people for the wings in and wings out operations, but otherwise it is a
one man job - 2 together will not speed it up.
Any questions??!!
David
G-BZAM
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