Regarding Carl's solution, how about using long pip pins made to order by
that outfit in Fort Worth.
The bottom of the pins would project through the bottom of the closeout and
would be inspected on every pre-flight inspection. The top of the pin would
be level with the top skin, and installed in such a way that they can only
be extracted with a small pair of longnose pliers for safety's sake ( I have
a similar arrangement with my regular pins). To make it easy to place the
pins, a piece of tubing could be installed inside the closeout down to the
edge of the TP12.
Karl
>From: glenn crowder <gcrowder2@hotmail.com>
>Reply-To: europa-list@matronics.com
>To: <europa-list@matronics.com>
>Subject: RE: Europa-List: Tailplane retention
>Date: Mon, 16 Jul 2007 08:22:20 -0600
>
>
> I like it. I'm doing it this way rather than trying to improve the TP6
>bond! Thats nuts!
>
> Glenn> Date: Sun, 15 Jul
>fklein@orcasonline.com> To: europa-list@matronics.com> > --> Europa-List
>message posted by: Fred Klein <fklein@orcasonline.com>> > Far be it for me,
>a humble late-builder, to chime in on this very > technical discussion
>thread; nonetheless, in the spirit of "open source > communication" with
>its underlying premise that an optimal solution to > the problem will arise
>out of the clamor, I have a few thoughts to > share. If I seem long-winded,
>my apologies, but clarity is my goal, as > I've had difficulty
>understanding some of the posts of others whose > brevity obscured (at
>least to me) some aspects of their intent.> > As I look at my "pre-glassed"
>tailplanes which came w/ my "accelerated" > kit, the first thing I notice
>is that the pip pin recesses as supplied > bear no resemblance to the
>drawings in the manual...at the skin > surface, the recesses are
>round...about 1.25" diameter...and taper down > to a .50" hemisphere in
>which is centered the hole for the pip pin. So > I really have no assurance
>as to what extent the TP6 is properly bonded > in or exactly what is going
>on...I ponder this while reading about > variations (such as TP6 location)
>which others are discovering.> > As I review Mod 73 and digest the
>insightful posts regarding the > process of accomplishing it, I can't
>escape my sense that...while it's > doable and apparently (at least to
>those with both the hands-on > building skills and technical knowledge to
>make such an assessment) > solves the problem...the mod seems like a bit of
>a band aid solution. > If I understand it correctly, it relies upon a
>proper bond between a > small crescent of a portion of TP6 to some bid
>cloth which transfers > any loads to the skin of the tailplane....I
>question whether I want to > rely on that bond to resist impacts from
>normal (and sometimes not so > normal) rigging.> > If the fundamental goal
>is to simply keep the TP12 pins fully engaged, > I'm looking elsewhere from
>the pip pins.> > I'm looking at the tailplane root close out which, on my
>tailplanes, > looks like about .088" of solid FG skin. I'm referring to the
>flanges > which measure a full inch in width...from edge to innermost
>surface of > the inboard plywood insert with the bushes which receive the
>TP12 pins.> > I liked Carl P.'s suggestion (as I understood it) of a
>hardened steel > pin extending thru both top and bottom skins and lying
>inboard of the > TP12 driveplate. The FG flange could be suitably
>reinforced...perhaps > with an embedded plate which could be threaded to
>receive a threaded > rod, thus eliminating fasteners extending beyond the
>plane of the > tailplane surface. I did not understand Carl's calling for
>the rod to > be 9" long, as the depth of the tailplane at the root is just
>under 5", > but perhaps that was a typo. The beauty of Carl's suggestion is
>that it > is simple and direct...it is completely visable anytime the
>tailplane > is slid away from the fuselage an inch or so...and the
>condition of the > "fix" can be monitored at any time in the future.> > Now
>that FG flange is only 1" wide, and the TP12 flanges measure 7/16", > and
>the bushes sit 1/16" proud of the glassed plywood...so...after a > (let's
>say) 1/4" dia. hole is drilled for a hardened steel pin to slide > past the
>TP12 drive plate, there's only a 1/4" left of the flange. It > would be
>sufficient however if the flange were reinforced with an > embedded plate
>which would allow the forces to be transferred to both > the top and bottom
>skins.> > The steel pin could be cut flush top and bottom; perhaps only the
> > bottom plate would be threaded, and the top end of the pin could be >
>slotted for a screwdriver so the pin could be turned in place (and >
>perhaps loctite'd?). For redundancy, there could be two pins per side > as
>Carl P. suggested for the faint of heart.> > With such a solution, the
>uncertainties of the conditions of the foam, > flox, TP5 placement, and
>other issues around the pip pins become > irrelevant.> > Amen...thanks for
>wading through this post.> > In the time it's taken me to write this, I may
>well have been able to > install Mod 73...and...there's always bee=====> >
> >
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