From: "dimple_kwok" <henry.kwok@...>
Date: Saturday, August 30, 2003 3:48 PM
Subject: Repost - The best method to make an extended wing and R1?
Date: Saturday, August 30, 2003 3:48 PM
Subject: Repost - The best method to make an extended wing and R1?
Hi
THE MAILSERVER SAYS there is delivery error, something about bcc not
allowed. I don't know how this happens...
I just scrapped a set of extended wings I have made because of some
twist I managed to build in, despite using a building board to pin
everything down :( Wasted a whole day of work
With everything pinned down the build seems to proceed quite smoothly
but once the pins are removed the wing warps (as in it won't sit flat
on the surface, which it should if built true because the back-ends
of the ribs are flat)
I suspect the reason for the warp was because of the CF spar
placement not being perfect. Because the spar holes are different
from stock, I had to estimate their positions as I built - and I
think that the warpping was due to accumulative error in the hole
placement.
What I have done was to have R1 and R7 fixed and the rod running
between them, and estimated the positions of each hole by placing it
next to the spar.
I wonder what your experience is and what tips you can give me to
avoid the same thing from happening again.
Also re: rib R1. If you slant it at an angle isn't this going to make
it stand shorter esp if you bevel the edges? I wonder if this
contributed to the warp. Is there any point using a thicker rib R1
and standing it straight up, and then sanding the root surface to the
correct dihedral later only after the wing is built? Just wondering...
Frustrated.