Shawn;
What I did in my case, and I feel good about the results, is the following:
My cradle is a weldment of 1" square tubing with 3 plywood saddles that
pick up the bottom of the "boat". I am able to move each saddle to twist
the fuselage and then C clamp it in place. Using the smart level in 3
places registering off of the joggle on the bottom I got the boat straight.
When drilling through the X's for the tailplane torque tube and setting the
bearings up tight I found that the tip of one end of the tube was 1/4"
closer to the firewall than the other. The tube also measured a 2 degree
tilt. This was not too bad as the tips magnify any misalingment back at
the holes. The holes were enlarged so I could get some movement (I only
needed to have one tip move forward 1/8" and the other back 1/8"). To
position the bronze bushings in their holes properly I made shims out of
layers of cloth carpet tape about 1/4" wide for fore and aft and up and
down. The tape worked especially well since it has some thickness and
being sticky on both sides it stays where it is placed. Though it took
some time I got the positioning where I wanted it (at least as good as I
can measure). The epoxy was placed around the inside and allowed to cure.
After that any tape sticking out was trimmed with a razor and the rest of
the bonding commenced. I am satisfied that I couldn't have done any better
and now consider it a "done job".
Steve Hagar
A143
Mesa, AZ
> [Original Message]
> From: Shaun Simpkins <shauns@hevanet.com>
<john@crixbinfield.freeserve.co.uk>; Miles McCallum <milesm@avnet.co.uk>
> Date: 11/20/01 7:09:08 AM
> Subject: Re: Tailplane to root fairing alignment, -and
servo pins
>
> All right, this is getting confusing and putting my SHORTS in a twist.
> If I go out and measure my raw fuselage bottom, the port stablilator
> fairing is at most 1/8" forward of the starboard fairing.
> The port torque tube crosshairs are 1/8" higher than the starboard
> relative to the tops of their respective fairings, but are equally far aft
> of the nose of the fairings.
> I haven't checked the waterline, nor the vertical displacement of the
> fairings from the waterline. Let's assume that they are the same for
> now. If there is no twist and you drill on the crosshairs, your
stabilators
> willwind up with the port end skewed forward and up, and the port root
> 1/8" higher than the fairing. If there's a twist, it could be horizontal,
> but
> still out of line with the fairing and still vertically misplaced.
> Untwisting
> a pure longitudinal twist could make things worse, since the crosshairs
> are misplaced vertically.
> So from what I see, the proper procedure would be to:
> 1. untwist the tail cone ( and hope that the twist is purely about the
> longitudinal axis ) if warranted.
> 2. measure aft equal distances from the firewall for the torque tube
> centers.
> 3. measure up equal distances from the waterline for the torque tube
> centers, but adjust to equalize any misalignment with the
fairings.
> There's another argument about whether twisting to align the tail is bad
> from a structural point of view...
>
> Shaun
> A207
>
> ----- Original Message -----
> From: "Miles McCallum" <milesm@avnet.co.uk>
> <europa@avnet.co.uk>
> Subject: Re: Tailplane to root fairing alignment, -and servo
> pins
>
>
> > Longitudinal position is fine - vertical position isn't - if you
"untwist"
> > the tail end in a jig...
> >
> > M
> >
> > > Forwarded from the bounce bin. Message is from
> > > "Cliff Shaw" <dm25shannon@home.com>
> > >
> > > ****************************************************************
> > >
> > > All
> > >
> > > I just went out in the shop and made a mesurement on my taleplane
torque
> > > tube. It is 141.5" from the front surface of the fire wall to the
front
> > > surface of the torque tub at its outboard end. Both P & S sides are
> > exactly
> > > equal. My installation was done on the scribed X points. It turned
> out
> > > right on the MONEY and I am happy.
> > > Cliff Shaw
> > >
> > >
> > >
> >
> >
>
--- Steve Hagar
--- hagargs@earthlink.net
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