|
7/13/03
Sunday Evening
Pat,
A friend of mine, Dennis Pratt, had a similar door problem
apx. 3 years ago. His problem did not originate in the window area (bolt
passing thru window) but was a result of a bad hysol bond between the door skin
and the door stiffener in the forward lower corner of the door. When the
bond separated, the door flexed and subsequently caused the window to crack with
similar results to what you described on your IV-P. Dennis' window
punctured the top layer of carbon and honeycomb in a couple of places on the top
of the wing - no damage to his flap. When we started dissecting the door
to get access to the hardware components we found several places that did not
have complete hysol contact. This was an incident that was just "waiting
to happen".
I don't think you will be able to salvage the door stiffener
and door skin because everything should be completely bonded together and I feel
like you would spend more time trying to separate the parts. My
recommendation is to order the new skin and stiffener along with the
window. This is what I did with Dennis' repair. The biggest
problem we had with his repair was making the new stiffener fit the door
opening. In order to maintain the 1/2 inch gap required between the
stiffener and the door frame (gap required for the inflatable seal), we had to
cut the stiffener and push out in several places to obtain the 1/2 inch
gap. I am not familiar with the recommendation to oversize the bolt holes
passing thru the window and fill them with silicone. We counterbored the
bolt holes apx. 3/4 inch in diameter and filled them with hysol as outlined in
chapter 28 of the manual. In my "opinion", the silicone doesn't offer any
support for the fasteners. This in itself may have placed undue stress on
the glass.
Dennis has over 800 hours on his IV-P (he travels a lot) and
I'm certain he has over 300 hours since the repair. For what it's worth, I
just finished assembling the door on my IV-P about two months ago and it took
about 3 weeks of work. We still have to fit the latch hardware which will
be completed after gluing the top half on the plane and then, of course, the
finish work. All in all, I estimate my door will take about half the time
it took to build Dennis'. This certainly adds validity to "the second one
is always easier".
Regards,
Ed Smith
Chesapeake, VA
|