Hi! Mike
It wasn=92t you who caused my concern, I felt that Jos=92s message
could be
read implicating my clamps (he must be excused because of the language
punctuation anyway) I need to come out of my box on the clamp issue to
speak for the clients who have invested in them.
However =85.I=92d like to proffer some assistance to those still to do
Mod
73.
The major problem is locating the pip pin hole underside of the tail
plane, especially if not drilled vertically (like mine :- my reason was
to not have two holes through the torque tube in the same plane to
improve the torque tube operational strength or that was the theory!) So
mine were drilled at quite an angle and had no drain hole since they
have a water tight screw cap fitted. To drill through from the top hole
would have punctured the bottom skin miles from the required bush.)
In the case of G-PTAG to locate the outboard rib was no problem, a
strong light across the surface shows up the minute ripple in the
surface under which is the rib. (wasn=92t there when the finishing and
painting was done but like the fuel filler straps does begin to show
externally over long term curing time)
The big problem is finding the torque tube alignment =85=85.I=92m
wishing I=92d
thought of this before I invaded my first tail plane ! Two quite
experienced eyes aligned mine but weren=92t sufficiently accurate and
I=92m
amazed how far out in the 12=94 distance we were=85.I found the rib as
above
but was initially digging the wrong way for the bush, my construction
will be therefore larger.
Now to the reliable fix of finding the tube alignment:- get a 5ft or 6ft
wooden lath (about 5/8 =93 thick) with straight edges which snugly fits
the inside of the tail plane bushes . Carefully stand the tail plane on
it=92s outboard end and insert the lath down the hole through the bushes
to engage with the inner bush then hang a builders plumb bob from the
top forward edge of the lath (with a drawing pin) to just clear the
close out flange by leaning the tail plane slightly towards the under
surface, align the plumb bob line with the same edge of the lath by now
tilting the tail plane in the 90 deg direction. The resultant plumb bob
line line will indicate the location of the forward edge of the torque
tube.
Measure =BE=94 back from the line will indicate the bush centre line.
Regards
Bob Harrison G-PTAG =85..lay up of Mod 73 to still do (excavation
complete!)
PS. MY bushes are/were still fixed solid, with hacksaw abrasion being
the original method used . (Not now so sure about the breaking of the
original bond by removal of the existing flox though !????)
Robt.C.Harrison
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Mike Parkin
Sent: 17 July 2007 11:38
Subject: Europa-List: Europa Tailplane.
All,
Bob, it was not my intention to tie in your modification with anything.
I was merely pointing out that the poor design had required
modifications such as your clamp and the increased diameter pins. I
appreciate that you want to get flying again and my suggestion was not
meant as the only answer. Plainly, the PFA in consultation Europa(2004)
will devise a mod or series of mods to solve the immediate problem.
However, in the longer term I do believe that the pitch control needs
modification. New kits certainly need to have a system that is stronger
and more durable. Perhaps along the lines that Graham is suggesting.
Certainly Carls pin idea and the latch system discussed are all worthy
of consideration for a long term fix for the current system.
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