Here is what I wrote to Jerry.
Let me say it was very pleasant to have a group of guys rooting for one in
the face of a great disappointment. Only someone who has built one of these
can understand the feeling of having made a significant mistake and having
to go back and correct it.
Thanks to all.
Will
"I have attacked the wing skin. Weapons of choice wood chisel, wood plane
and sanding disk. Thatll teach the bugger! New skins ordered.
No way that I can see of saving the skin or more accurately - might save
the skin but ruin the wing
I thought of making a new top skin (making a polyester mould) but discarded
this idea when I realized that the upper skin changes in construction from
tip to root the root area is considerably stronger.
Two steps forward one (and ) steps back."
Will
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Fred Fillinger
Sent: Sunday, January 15, 2006 13:17
Subject: Re: Europa-List: Wing skin separation HELP
My attempt to soften Redux, after it had cured a couple weeks, was too a
failure. Too much heat required, verses heat to damage the glass
structure, which conducts heat poorly to get at the green stuff. For my
safety at least, I would be assuming this procedure might give me a
potential airworthiness problem to forever worry me in severe
turbulence.
I'm surprised the factory would advise -- not knowing any builder's
skill level -- removal by any method other than panel destruction and
replacement (requiring essentially $$, that's all!). Otherwise a
Hobson's choice on structural integrity, attempting a fix, the moral
equivalent of "don't force it...use a bigger hammer."
I don't have this style wing, but merely perused the XS manual online.
It's my opinion that the primary purpose of the tapes is such that
improper orientation of the fibers matters only a little, but I have no
credentials to say that. But, when we add two more tapes, we do stiffen
the ass'y there further, concentrating stresses elsewhere. That could
mean a "seven yard gain, with a five yard penalty," as in U.S. football.
So, if the factory can analyze that one with engineering analysis to say
no harm, they should be able to say computationally why -- in stress
paths -- 90 on the tapes is not good. Or more likely just their gut
reaction and "usual rules" for FG construction.
The only thing I would not do was a fix which may compromise the
structure worse than the original problem.
Reg,
Fred F. (nickname "Hobson")
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