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Old Jan 20, 2013, 04:19 PM
jetinteriorguy is offline
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Burke, VA
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Originally Posted by LoneWolfRC View Post
Many very good pilots only mess with the deadbands. I'm not a very good pilot, so I try for perfection in servo setup. (I think I first achieved in on my 48" MXS).

Others have reported, and it makes sense to me, that it's a good idea to setup those programmable servos that have the option to reduce power in the event of over current. Not all of the programmable servos have this feature, though. The 5245 do not if I remember correctly, but the 7245s do.

Another think you can do is set up your ailerons and rudder for symmetrical defelections for symmetrical throws. This probably makes the most sense on the ailerons and rudders. Doing this is complicated, however, by both the hitec software, and what they consider 0, versus what your radio considers 0.

That issue aside, the easiest scenerio is when your control surface control horn hole for the control horn is perpindicular to the hinge line. In this case, set your 0 for the servo arm to be 90 degrees, and then you should be able to set your zero and end points even without a programmer.

For this reason, I personally try to not install control surface control arms in until after I have CA'd the hinges. That way, I can trim the control surface control arms if necessary to try to get the holes over the hinge line.

If for whatever reason that is not the case, what follows is speculative on my part, but I think DJMoose has said this is true somewhere if I remember correctly (I just haven't done the math to verify it). If the control surface control horn hole is not over the hinge line, that is, that the hinge to hole angle is not 90 degrees, adjust the zero of ther servo control arm to be the same angle. I suspect this is about right, but like I said, I haven't done the math to verify that it is always true. For example, there might be an angle offset based on the lengths of the control surface control horn hole to hinge line length, when that length differs from the servo arm hole in use to servo arm mounting screw length. I usually end up doing trial and error here in practice, and it is time consuming, frustrating, and one of the issues where the law of diminishing returns might. There are a finite number of splines on the servo control arm, and this is where programming a new center at the servo can help. This is where some nice diagrams and a bit of time with some trig. will come in useful.

But since the PWM for zero used by the hitec programmer probably differs from your radio (it does for Spektrum), this is also a time consuming process. This summer I plan to measure the PW of the hitec programmer zero, and compare it to various spektrum receivers, and see if there is any consistency and and a consistent offset error. Such a measurment, if it is consistent, will reduce some of the frustration. Similar measurments would be necessary with hitec, futuba, etc., receivers.

It will be tough, as my rambling paragraph above alludes to. And, I think most people aren't so anal about the servo setup. I am, because I want to know that all of my bad flying is my fault
You can sure tell it's January in Minnesota.
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