Hi Rob and all.
I too reduxed the spar bushings in place using the factory supplied dummy
spar. My wings were stored in a friends barn, due to limited space in my
garage, and to speed up things I found it convenient to simply use the
dummy. Prior to this I checked the spacing between the holes against those
on the spars and everything matched perfectly. The 1/2" inch bolts supplied
slid in and out without a hitch.
Now to the strange part: After some time, and having installed the cockpit
module I reinserted the dummy spar - just to make sure that everything was
OK - and found it impossible to insert both bolts! By peering into the stbd
hole with the port bolt inserted I found a slight misalignment - a half mm
or so. I started to tremble with all bad thoughts about my inability to
build correctly, when I pulled myself together and machined a new dummy spar
out of thick plywood and a new set of bushings. Dimensions were taken from
the cockpit module - and both the new dummy and the old one were brought to
my good friends barn to check them against the spars. To my suspicion the
factory supplied dummy showed the same misalignment, while the one I built
fit perfectly - confirming that all was well regarding alignment. Much to my
relief!!
It's obvious then that a certain expansion has taken place to the company
supplied dummy spar over time - after my work on the bushings. What's caused
it is a mysteri, but it's made of some sort of compressed materiel, and my
bet is that it has been influenced by atmospheric conditions.
Be cautious out there!
Hans.
----- Original Message -----
From: "Rob Housman" <RobH@hyperion-ef.com>
Subject: Re: Wing angle of incidence
> In re: 1.
>
> If I understand you correctly you have a WIDE gap to fill between the W27
> assembly and the fuselage. If you followed instructions you may be deep
in
> something you rather not be in. I say "may" because the pins supplied
with
> my kit (A070, one of the first XS kits) had the pip pin hole drilled way
too
> close to the wing root, and had I bonded that pin into the wing root when
> instructed, I would not even have been able to get the pip pin into the
> hole. Fortunately I had the pin in place, but not bonded in place, when I
> began installing W26 & W27, and I discovered that the hole was so close to
> the wing root that it was not possible to mate the W26 assembly to the
wing
> pin. The replacement pins supplied by Europa were drilled further from
the
> threaded end of the pin. Obviously the "relocated" pip pin holes put the
> W26 assembly closer to the fuselage. If your pip pin hole is too close to
> the wing root and the pin is already bonded to the wing root, I am not
sure
> what to recommend other than to check with Andy or Neville. You may need
to
> remove the pin.
>
> In re: 2.
>
> Sorry, but I have no useful comments.
>
> In re: 3.
>
> This sounds entirely too familiar, but you may be luckier than I. First
> check that there is no epoxy inside any of the wing spar bushings. The
> factory was a bit sloppy in making my wings so there was a some in each
> bushing. It doesn't take much, and it is hard to see (clear epoxy in a
> black hole), especially since it never occurred to me to check for sloppy
> work. Unfortunately, cleaning out the bushings was not sufficient to get
> things to fit. My XS wings fit fine, but ONLY one at a time, and the two
> wing spars will accept both spar pins as long as the wings are not in the
> fuselage. There seems to be a slight difference in spacing, wing to wing,
> but I have an additional greater error in the location or alignment of the
> seat back bushings, and it may be that both the alignment and spacing are
in
> error. I barely have a big enough hammer to fit the spar pins with both
> wings in place. I attribute this to the fact that my early XS project was
> built out of sequence because when I was ready to continue, the wings were
> not available so I built the fuselage first and used two factory supplied
> dummy spars for bonding the bushings into the seat backs. That's right,
two
> dummy spars, because the first one did not seem right so I asked for a
> replacement. The centerline distance between the holes was not the same,
so
> I arbitrarily picked the second one and used it. BIG MISTAKE. To see how
> badly the alignment really was I machined several dummy spar pins at
various
> undersize diameters to see what would fit. At about .050 inch / .013 mm
> undersize the dummy spar pins fit without needing the big hammer.
> Conclusion: I will remove both seat back bushings and replace them, this
> time with both wings in place, because my preference is to avoid making
any
> changes in the factory made wing spars. I have yet to do this because I
am
> waiting until I have the landing gear installed (this is a Tri-Gear, with
> mains in place and the nose gear is almost finished) so that the fuselage
> will stay in place while fitting the wings.
>
>
> Best regards,
>
> Rob Housman
> A070
>
> -----Original Message-----
> From: forum-owner@europaclub.org.uk
> Behalf Of Chuck Popenoe
> Subject: Re: Wing angle of incidence
>
> Dear Collective Wisdom-
>
> I'm about to attach the lift pin sockets to my Classic (with MTOW mod) and
> have a couple of questions:
>
> 1. The manual states that you may need plywood shims under the W26 & W27
> sockets. The gap between the fuselage side and the sockets are about 12 mm
> with the greatest one 14 mm. This seems excessive, but that's what they
> measure. Is this normal? Also, the manual doesn't mention it, but I
assume
> that you have to grind a relief in the root rib flange to allow insertion
> of the pip pin.
>
> 2. The washout of the two wings differs! (with my meticulous--read SLOW--
> building, I can't figure how this happened!!!). The 70% span starboard
wing
> incidence measures 1.4 deg. when the root is at 2.5 deg. Not bad! But
when
> the port wing 70% span section is set for 1.5 deg. its root incidence is
2.1
> deg. Much less twist. So, I programmed an Excel spreadsheet to sum the
> sectional lifts and moments at 1 ft. intervals, and diddled the incidence
> until
> the lift moments of the two wings balanced. The best result is when the
> stbd.
> wing is set for 2.55 deg. at the root, which gives 1.45 deg. at 70%, and
the
> port wing root at 2.1 deg., which gives 1.5 deg. at 70% span. The sums of
> the lift-moments are exactly equal with this setup. Any comments pro or
> con?
>
> 3. Now, the tough problem--it is REALLY hard getting the spar pins in! I
had
> easy pin insertion before converting to the MTOW 1/2" pins and bushings.
I
> very carefully transferred the geometry to the new bushings, using 1/2"
> bolts
> to cast in place the new bushings using the old bushings as jigs. The two
> wings
> alone allow easy pin insertion. When I insert the port wing alone, the
pins
> slide
> in with no problem. I then slide in the stbd. wing and the port pin--no
> problem. Then, the stbd. pip pin gives me fits getting it in, even with
> grease,
> etc. I can barely get it inserted, but the pin will barely rotate once it
> is in. Way too tight! I'm afraid that I will never be able to rig the
> wings
> once all of the lift pins, flap pins, etc. are in place. I believe that
the
> bushing spacing must be off by a half mm or so in the stbd. wing.
>
> I have pondered on this, and have come to the conclusion that I will have
to
> either remove the stbd. bushings in the wing and try recasting them in
situ.
> Or, another scheme would be to assemble the wings, substituting a 1/2" OD
> tube for
> the pip pin, brute force into into place, and insert a heating element
> inside to
> soften the Redux in the stbd. wing bushes, allowing some time to relieve
> stresses,
> i.e. to have the Redux flow or creep slightly. This seems like it might
> work.
> What do you think?
>
> Thanks for any suggestions!
>
> Pops
> A036
>
>
> -----Original Message-----
> From: forum-owner@europaclub.org.uk
> Subject: Re: Wing angle of incidence
>
>
> Cleve,
>
> Yes, unless for some reason the bushings that you glued into the module
are
> very out of line. Which would be hard to do. The bushings allow for at
> least the required amount of play to get the 2.5 degree angle of
Incidence.
>
> Bill McClellan
> A164
>
>
> ----- Original Message -----
> From: <clevelee@cswebmail.com>
> Subject: Wing angle of incidence
>
>
> > Collective Wisdom,
> >
> > I'm about to go about setting the wing incidence. I am puzzled by an
> aspect of
> > the mechanics.
> >
> > The pin busings that were bonded into the cockpit module did not have a
> specific
> > wing angle of incidence associated with the installation.
> >
> > Does it really work, that with those bushings already bonded in place, I
> can
> > expect to rotate the wing spar relative to the outside of the fuselage
to
> obtain
> > the 2 1/2 degrees incidence, and still expect the pin passing through
the
> > cockpit bushing to slide smoothly into the spar bushings?
> >
> > What am I not realizing?
> >
> > Thanks,
> >
> > Cleve Lee
> > Mono XS A198 N396ST
> > Detroit, MI
> >
> >
> > ___________________________________________________
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>
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