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Old 03-27-2005 | 08:00 PM
  #493  
JRW
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Joined: Oct 2002
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From: lancaster, CA,
Default RE: Impact

HI All,

After some deliberation I decided to jig the fuse such that the nose had 1 degree down thrust, then made zero lines for the stab (zero) and wing (0.25 degree) from my table. Everything is drying now and I feel that the results of this method came out pretty good. Used some home-made height gages, and everything looks spot-on while it is drying now.

Caution: I found two areas of caution, that are not intuitive: 1.), the aft pin of the horizontal stabs are not true, nor conisistent with each other. While the larger stab tube of both 1/2's were true, the aft pins of both stab 1/2's pointed "down" at some angle. Thus, not knowing this when I drilled the first perfect set of holes on the fuse, I had to adjust them downward and aft some (around 2-3 mm) to keep the stab 1/2s at zero degrees. Because of this, it was impossible to use "one" carbon pin to join both 1/2s, if I had wanted to, as they were intersecting each other at angles. 2.) The second concern totally stumped me for a few minutes. The aft aligment holes in the wing, while drilled "true", are not on the center of the rib!!!!!!!!!! When I first installed the wing, I had nearly 1 degree of NEGATIVE incidence, instead of 0.25 positive incidence. This took the majority of time to reposition and get perfect again.

With the wings finished and the cornes rounded, I found it difficult to find a congruent location to take alignment measurements from. I decided to measure from the fuse down the LE of the wing, until just before it started to make the radius. I made a small mark equal on both LE's. The "obvious" spot to use was the outboard corner of the ailerons, as they were factory cut I figured they would be "exact" to one another. However, after taking a bunch of different measurements, these were not the same on both sides, and again I settled on the LE position. Using this, the right wing tube hole needed just a smidgen of adjustment, to get equal measurements from these outboard LE marks to the top of the vertical fin. Also, this happened to "even-out" the little bit of wing -root that was not matching the fuse.

All-in-all, the alignment would have been 2/3rds faster had I taken the time to measure up the factory drilled holes. The plane looks really nice the garage, sitting with stabs and wings on!!!

One Question Please: Like everyone else, I'm considering how to mount the ailerons and elevator servo(s). The instructions show the "root" and "hatch" mounting methods. If you can cut a "hatch" in the skin, why hasn't anyone just mounted the elevator and ailerons servos upright, and in typical installations? With just a little enlargement of the servo horn slots, you can mount the servos vertically?????

Thanks for everyones posts!!
Jim W.