AboveMSL
Well Known Member
Hi Folks,
My horizontal stabilizer rear spar is misaligned. I have looked at E’s blog, and hiplanesdrifter’s posts and my symptoms vary somewhat from theirs.
All rivet counts are from outboard edge.
1) The LEFT BOTTOM skin holes align perfectly.
2) The LEFT TOP skin holes misalignment begins at the 19th hole and gets progressively worse toward the outboard edge. Progressively worse meaning the angle at which the rivet sits in the hole increases.
3) The BOTTOM RIGHT skin holes are misaligned from hole 10 and move outboard.
4) The Top RIGHT skin holes are misaligned from hole 29 and move outboard.
5) Additionally, if I cleco the skins to the spar without cleco’ing the spar to rib holes, the 2nd and 3rd (from inboard) LEFT inspar ribs holes are misaligned.
I have contacted Van’s and they are willing to send me a new rear spar with no holes prepunched in the flanges. I’m appreciative of the good customer service and see no better solution, however, I do have some apprehension with match drilling all of those holes. My concerns are these.
1) The skins are already dimpled, will that affect the accuracy of match drilling?
2) Dimpling likely enlarged the skin holes slightly, will drilling through them, as a guide hole, enlarge them further or misshape them?
3) Is there a particular order I should follow when drilling. I’m thinking inboard to outboard, top and bottom of one side, then the other?
Any thoughts would be appreciated.
My horizontal stabilizer rear spar is misaligned. I have looked at E’s blog, and hiplanesdrifter’s posts and my symptoms vary somewhat from theirs.
All rivet counts are from outboard edge.
1) The LEFT BOTTOM skin holes align perfectly.
2) The LEFT TOP skin holes misalignment begins at the 19th hole and gets progressively worse toward the outboard edge. Progressively worse meaning the angle at which the rivet sits in the hole increases.
3) The BOTTOM RIGHT skin holes are misaligned from hole 10 and move outboard.
4) The Top RIGHT skin holes are misaligned from hole 29 and move outboard.
5) Additionally, if I cleco the skins to the spar without cleco’ing the spar to rib holes, the 2nd and 3rd (from inboard) LEFT inspar ribs holes are misaligned.
I have contacted Van’s and they are willing to send me a new rear spar with no holes prepunched in the flanges. I’m appreciative of the good customer service and see no better solution, however, I do have some apprehension with match drilling all of those holes. My concerns are these.
1) The skins are already dimpled, will that affect the accuracy of match drilling?
2) Dimpling likely enlarged the skin holes slightly, will drilling through them, as a guide hole, enlarge them further or misshape them?
3) Is there a particular order I should follow when drilling. I’m thinking inboard to outboard, top and bottom of one side, then the other?
Any thoughts would be appreciated.
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