Been there, done that. Fortunately I discovered that the pip pin holes
would not align prior to bonding the wing lift pins into the aluminum plates
in the root rib. You apparently missed my earlier posting where I suggested
checking this alignment prior to bonding the lift pin into the root rib.
The manual instructs you to screw the pin into the root rib as far as it
will go - big mistake if you do this (and you apparently did). I early on
realized that there was NO apparent quality control in the manufacture of
the XS wing (see, for example, in the archives my earlier posting regarding
the invisible peel ply left on the root ribs) so I skeptically verified that
all mating items would actually mate before I bonded anything in place.
While I can verify that you are not the only builder with this particular
problem I can not offer any suggestions for mitigating this disaster now
that the lift pins are already bonded. On second thought, there is a
possible easy fix. See the following paragraph.
Check that the lift pins are in the right place relative to the hard points
in the fuselage. I had the choice of relocating the hard points or moving
the lift pins, after already drilling and tapping the aluminum in the root
ribs (obviously I failed to follow my own advice about checking alignment
before drilling). I chose to drill and tap holes that would put the
fuselage hardware squarely in the center of the hard points because drilling
and tapping is much easier than moving the hard points. Here is where two
"wrongs" might make a "right" for you. If you can relocate the lift pins
you can simply (OK, not so simply) cut off the pins you have already
installed and drill and tap for new pins, but of course you need to locate
the second holes far enough from the existing pins - about one hole diameter
distance from edge to edge should be adequate, especially since your
original hole in the aluminum is now reinforced with a steel plug. The very
useful Dremel with a reinforced cutoff disk will cut the steel pin, just not
very quickly.
It gets worse, if you are building a tri-gear. Be thankful you are not. My
manual (30 July 1999 edition) calls for installation of the tie rod between
the W26 assemblies prior to installing the main gear leg sockets. Had I
been foolish enough to follow this sequence it would have been difficult (to
put it mildly) to install the main gear leg socket bracing because once the
tie bar is installed it can not be removed without cutting fiberglass, and
it definitely would be in the way.
For either the tri-gear or the monowheel, installation of the tie bar is, to
put it politely, tedious. Before drilling any holes and before mounting the
attachment "brackets" to the bulkhead behind the seat backs check for
alignment. The sixteen bolts (three each side through the fuselage side and
five each side through the "fish plates," the bracket, and the tie bar) took
me about sixteen hours to install because I blindly followed the manual's
instructions about where to put the brackets and the holes. Without the
tri-gear's gear leg socket reinforcements in the way, the tie bar
installation would have gone much faster but the various parts still would
not have been properly aligned. Nothing fit right, and some of the bolts
are so long that they try to occupy the same space as some other part or
another bolt - at least the bolts are easy to shorten with a hack saw, but
this should not have been necessary. You will also need an aircraft length
drill bit to make the holes in the brackets because even a very small right
angle drive drill can't drill a hole within about one hole diameter distance
---From the bulkhead.
Best regards,
Rob Housman
A070
-----Original Message-----
From: owner-europa@post.aviators.net
Subject: lift pin sockets
Is there anyone still out there? I guess the list has gone even quieter now
that Oshkosh is on. But for any poor souls like me stuck at home still
building - any advice on this one.
Have just bonded in the wing lift/drag pins and the flap drive pin at which
point a few things became apparent:
1) the rear lift pin socket W26 has been completely redesigned and now comes
as three parts.
2) The whole of chapter 27 had been re-written to include this fact and a
hole pile of additional work to install tie rods etc. Good job a ruined a
lift pin and had to ring the factory for a new one otherwise I would have
been none the wiser.
What I now find is that the W26 lift pin socket on the port side 'bottoms
out' on the aluminium plates bonded into the wing root (onto which the lift
pin is bonded) before the pip pin holes align. There is about 1.5mm
discrepancy. I'm not entirely sure the lift pin hole has been drilled and
tapped perfectly horizontal. Any one had similar experience or suggestions.
I think it has been said before, but the quality control of the XS wing to
my mind leaves a bit to be desired.
regards
Paul Stewart #432 XS mono
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