.and I can assure you, Christoph, that the hammer and pry bars would not
have worked. When brute force failed I took the more drastic approach - I
cut the added glass with a Dremel driven abrasive, sort of like a dentist
drilling a tooth, and still needed a bit of heat from a propane torch to
release the bond. The surprise was how well the epoxy bonded to greased
metal and that gave me a lot more confidence in my structural bonds
elsewhere, where I did a thorough job of cleaning and roughing the surfaces
to be bonded.
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Christoph Both
Sent: Monday, September 29, 2008 8:47 AM
Subject: RE: Europa-List: Mod 72 - Undercarriage mounting frame
strengthening
Rob,
I can really feel with you, having just completed MOD 73. The manual falls
short to say that you ought NOT to insert the tail planes so deep into the
torque tube that the two retaining pins would contact or even insert into
the bushings fitted to the tailplane root.
I was lucky on the first one which refused to insert because the layup is
performed on the opposite side. It was EASY to crack the torque tube to
retaining layup by TWISTING the tailplane against the torque tube. Came
right off no problem. I was not worried either as the inner tube was
greased.
What compelled me with my second tailplane to push it that far in to allow
the pins to insert I don't know as I should have used my head, not the
description in the MOD manual. Next morning wanting to separate the
tailplane from the torque tube turned out to take several hours. Yes, I
admit I showed up with a hammer, pry bars etc, but after initially starting
to damage a bit of the root layup by prying I decided not to proceed.
Instead I disassembled the entire torque tube which had been there for years
and took all out. Took me 2 hours. From there it was easy as the pin
retaining welded part could be removed and the tailplane cracked loose by a
twist.
In hind sight I am glad I did not use the hammer. This can be extremely
damaging to internal parts in the tailplane like hair cracks. My
recommendation is to just insert the torque tube sufficiently into the inner
tube at time of layup so that pins stay out of the way. This should be added
to the current MOD 73 instructions.
Best,
Christoph Both
@223
Wolfville, Nova Scotia Canada
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Rob Housman
Sent: Monday, September 29, 2008 11:52 AM
Subject: Europa-List: Mod 72 - Undercarriage mounting frame strengthening
Having been working mostly on those factory mandated or recommended
modifications of late, I now realize that it is much easier to build an
airplane than it is to repair one. Mod 70 (Mass balance arm) was merely
tedious, working deep in the tailcone, one handed, through small access
holes, but Mod 73 (Tailplane retention) and Mod 59 (Shimmy damper) did not
go well when following the written procedures, and now with Mod 72 there is
more of that wonderful English understatement: "Insert the tubes - they will
probably need a light tap to fit them" it says in the procedure. English
hammers must be considerably larger and heavier than American hammers (or
16.5 mm reamers must be a bit larger) because "a light tap" does nothing.
After pounding away for entirely too long, and peening the ends of the tubes
where the hammer repeatedly struck, I finally fabricated a steel spud to put
between the offending pin and the hammer. This made it easier to keep
pounding with less damage to the pins, or to the adjacent smaller diameter
tubes to which the engine mounts attach if I were to miss the target. The
steel spud is starting to look like a mushroom from all of those "light
taps."
I should have retained my initial skepticism regarding the fit of painted
tubes, which after painting with etch primer are larger than 16.5mm, but no,
I foolishly believed that the factory had actually tried this procedure.
Well folks, the paint makes the pin almost impossible to fit.
Fearing complaints from my neighbors about so much hammering on a peaceful
Sunday afternoon I finally quit pounding with the intention of resuming
mid-day today when most of my neighbors will be away at work. As of
yesterday afternoon one pin was snug against the bolt attaching the frame to
the fuselage and the other was still barely halfway home.
Now, if I could find one of those English hammers at Home Depot..
Best regards,
Rob Housman
Irvine, CA
Europa XS Tri-Gear
A070
Airframe complete
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