Mailing List lml@lancaironline.net Message #18892
From: Larry Henney <LHenney@dellepro.com>
Sender: Marvin Kaye <marv@lancaironline.net>
Subject: RE: [LML] LNC2 Horiz.stab hinge center line
Date: Thu, 22 May 2003 10:12:45 -0400
To: <lml>
Message
Has anyone had this problem and is there a better way to find the centerline than splitting the difference at the hinge points?
 
Yes Dale!
 
The factory is absolutely correct.  I made this mistake and have a disgusting fix to recenter my hinges.  Your thought to adjust the hingeline toward the skin which remains to be attached is excellent.  My error was close to 1/8".  The question is how much do you compensate?  I would imagine that if you placed nickels (with superglue) all over the cap strips you would get very close to the final centerline.  The nickels will approximate your hysol flox build up.    If you're a low flox high weight kind of guy perhaps a dime would be adequate.
 
During the actual installation with hysol, there of course is some variability based on the number of shot bags or weight that you put on top of the skin.  This is pretty arbitrary however since you cannot reverse your direction of adjustment (take off weight and hope the skin will rise).  Additionally, the final edge trim will most likely not have  been done so where you measure to is somewhat arbitrary.
 
In any event, if you find the hingeline slightly off be careful with your correction.  I slotted my hinge holes to allow the offset.  This of course would allow the hinges to move over time as the glass slowly compresses.  To compensate for the eventual movement, I slopped a little wedge of flox at the bottom of each hinge so it could not move.  At high speed on one particular day, the flox popped off giving a nice little pitch jerk in my flight controls.  Moral of the story, if you do any sort of hinge slotting repack the holes with flox upon assembly.  Of course the better fix would've been to buy undrilled hinges and offset the holes.
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster