Andrew, A couple of points possibly of value :
1) When setting up the wings the manual (or at least my version of it) talks
about checking that the distance from wing tip to tail on each side is the
same. This manoevre led me to all sorts of confusion, which was only settled
when I realised that there is only one sensible location for the spars and
that is tight against the seat back. You definitely do not want the spars
set back from the seat back with the spar pins bridging the gap, which would
be asking the spar pins to do more than they are designed for. I would
advise setting up the spars with some pieces of wood jammed behind them in
the tunnel to ensure they are tight aginst the seat back. If one wing tip is
a 1/2" closer to the tail than the other it is because the fueslage or your
fixing of the cockpit module is less than absolutely symmetrical, but it is
of no consequence.
2) The location of the spars gives an approximation to the right
rigging angle for the wings, but the precise angle is set by your
positioning of the lift pins. I would strongly recommend buying or borrowing
a Smartool (which measures to 1/10 degree, to ensure that you get the two
wings set as close the same angle as possible. Even a small difference in
rigging angle will of course leave you with an irritating lateral trim issue
and quite possibly to a built in tendency to drop a wing in the stall.
Regards, David Joyce, G-XSDJ
----- Original Message -----
From: "Andrew Sarangan" <asarangan@gmail.com>
Sent: Tuesday, November 29, 2011 6:57 PM
Subject: Europa-List: Setting angle of incidence for bonding spar alignment
bushes
>
> I am about to embark on bonding the spar alignment bushes into the
> cockpit module (chapter 14). The manual says to set the wing spar
> parallel to the front of the seat back, and that this is good enough
> for now. That seems rather arbitrary to me, given that the tolerance
> required later is 2.5 +/- 0.05 degrees. I am confused how the angle of
> incidence can be adjusted in the future with the bushes already bonded
> in. Would it not be best if the bushes are bonded after setting the
> 2.5 deg incidence? But then I am uncertain how to infer the angle of
> incidence with the cockpit module sitting face down on the floor. Any
> thoughts from experienced builders would be appreciated!
>
>
>
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