Cheers -
LIke many. I have been delaying this first big layup because I was not
confident that I had fixed the 3 foward foam cores in the proper
position to fix them in place. I abandonned the "four stick base" idea
because of a flexible interior floor - in favour of a Warren Truss made
of Dexion shelving and bolted only at the ends throught the floor. It
woirked, however getting the 'tang' of the spar to lie horizontal in
both planes was a teaser.
Eventually (I'm slow) it dawned on me that slight irregularities in
the internal spar were not nearly so critical as was the "tang" - the
central part of each spar where bolting to fuselage occurs.
I found a piece of 1-1/8 x 10 x 42 inch hardened chipboard (Brit HD?
material which appeared and proved to be (a) almost immoveable, (b)
straight as a die and (c) easy to drill vertically. This I drilled to
match the 3/8inch pin-holes by which the qwing is fixed. I then mounted
the board hard to the spar (like a table over the 'tang) and then
adjusted the spar on the truss ubntil my digital level registered the
board perfectly horizontal. I then fixed straight aluminum bar along
both inboard and outboard foam cores datum lines, and can now be assured
that when the 'tang' is level, the foam core centres are vertical (at
90deg to same). I can even 'see' the washout now.
Anyway, I feel much better!
Happy landings
Ferg Kyle #A064 (319)
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