Archive of the Yahoo! Groups mailing list for the Bug hand-launch glider 2002-2018

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?
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.