ORIGINAL: mglavin
ORIGINAL: bodywerks
the hingelines on my Aeroworks 35% 260's elevators are slightly off, placing one elevator half slightly higher than the other. To most, this is probably never even looked at. Then, to top it all off, I misdrilled the control horn by about 1/8" on one elevator half. Both control horns' fulcrum is directly over the hingeline still, but one is 1/8" outboard compared to the other. It doesn't seem like a big deal, but, like Mglavin said, no amount of additional mechanical tinkering or servo programming will ever fix it, not even a Hitec servo programmer. The other thing I noticed (I use the two rods coming to a point behind the rudder trick, too) is that, while I can adjust my ATV's to achieve the exact same throws for a given rate, they still don't move at the exact same rate all the way up to their endpoints[:@]. Besides the obvious geometry problems one can encounter, other factors, such as variences in the servo or servo arms themselves, or a little extra friction in the hinging of one control surface or ball joints campaired to the other, can also reek havok. The best thing to do is to get rich and get sponsored. That way, you can afford a pro-build instead of the chinese stuff, and can have buckets of servos lying around so you can mix and match them to get exactly what you want!
Perhaps my comments were absorbed out of context. You CAN remedy ill installed linkage scenarios with the proper approach mechanically; iteration is the key to resolving problematic miss-matched linkage/surface/geometry. For the most part you can match servo angle with like ATV values and surface deflection, while the ratios maybe slightly different the end result is what were after.
Are you implying your control arm is offset span-wise 1/8" different than the opposing control arm? If you’ll provide the numbers I can likely work out a best case linkage setup. At the very least we can see the numbers your realizing.
There's one other thing I didn't mention. besides being offset, actually about 3/32", spanwise different than the opposing control horn, the geometry is nearly identical. I even put a spacer under one of the control horns to adjust for the one elevator half that had hinges installed slightly off center. I can also get the travels to end at exactly the same spot using ATV's when I am in high rates, but then it is way off in low rates. What I ended up doing was making a compromise between the high and low rates - now they are both slightly off.
My understanding is that some of the top Futaba radios have adjustable end points for each rate. Unfortunately, JR does not...
One thing I might be able to do, though, is use a couple of my multi-point mixes instead of my dual elevator function and set one mix up for my low rate flight mode, and the other mix for my high. I may have to try that.