Posted for "sbej" <sbej@verizon.net>:

I cant seem to get the rudder to go full deflection without rubbing on the
vert skins. The rudder is slightly wider than the vert where the hinge line
is. The gap is pretty substantial right now when in fair position. Even with
this large gap they still cant go full deflection without rubbing in some
areas. I did a test with a a peice of scrap glass to see if I moved the vert
trailing edge out further to similate a fatter vertical but I still dont see
that as a solution to the large gap.

If the rudder was off to one side slightly on the hinge line it would most
likely cause a problem on one side only but I have this problem on both sides.
Ive been trimming the vert trailing edge shorter and shorter and its helping
but also opening up the gap.

Anyone else have this problem?
Bryan
 
[It sounds like the problem you're having is similar to what I faced when fitting the elevator to the stab on my kit.  The elevator leading edges didn't want to stay cncentric to the hinge line that was available with the spar placement as it came from the factory on my fast build. 

The leading edge of your rudder must be circular in cross-section with that circle's axis co-located with the hinge line.  That circularity only needs to exist in the area that is visible throughout the range of travel on the rudder, so it's possible to have a flat leading edge that stays hidden while the arcs that are visible are free to travel within the trailing edge gap of the vertical stab.  The problem is that the concentricity of that leading edge circle on the rudder may not be off from side to side, but from front to back.  Just because the visible portions of the rudder LE are round doesn't mean that they are necessarily concentric to the hinge line. 

I've attached several drawings to this post so to help visualize what goes on when you move the hingeline forward and back.  The drawings are labelled with what was done to the hingeline axis (relative to the concentric rudder hingeline) to show the effect when the rudder is rotated through 30 degrees either side of center.  The drawings are exagerated a bit for clarity, but they still show what you have to deal with when battling those concentricity issues.  One fix entails adding material to the rudder LE and sanding it back until the LE is concentric with the hingeline... that can be verified by its relationship to the vertical's TE.  Another fix entails relocating the hinges... I pretty much guarantee that you probably don't want to go there.  Unfortunately there is no really simple solution, but it can be made to work as long as the hingeline is straight and no farther out of concenttricity than the TE/LE gap distance.  Take a look at the details of what I went through with my elevator and stab on my website to get an idea of what I had to do to solve this problem... it's pretty well covered there.

I hope this helps.    <Marv>   ]