Minimizing control surface throw
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From: Sioux Falls,
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If I want to minimize the amount of movement on a particular control surface, say for example an elevator, would I move the pushrod to the inner-most hole on the servo arm and the inner-most hole on the control horn? Or is it inner-most hole at the servo, and outer-most hole at the control surface?
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You will loose a tad bit of resolution doing this, however, it is the only way, other than setting end points using the computer part of a computer radio. If precision is not an issue (pattern flying) then resolution is not such a big a deal.. however, the more you fly, the more you will begin to appreciate those finer adjustment points.
DS.
DS.
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From: , MD,
CGRetired,
I'm slightly confused...how will this lead to a reduction in the resolution? If anything, I would think it would increase the resolution. I understand how changing the end points affects the resolution...is that what you were speaking of? Thanks!
I'm slightly confused...how will this lead to a reduction in the resolution? If anything, I would think it would increase the resolution. I understand how changing the end points affects the resolution...is that what you were speaking of? Thanks!
#6

CGRetired - Are you saying that what Dragonslain and Britbrat said to do would reduce resolution? You're gonna need to explain that one to me as well.
Did you also say that resolution is not a big deal in Patern Flying? Again I would require an explanation of the logic in that statement as I see none.
I will agree that the more one flies the more he will appreciate finer resolution in SOME planes, but not all people. Some people just blast holes in the sky and couldn't care less about precision.
Did you also say that resolution is not a big deal in Patern Flying? Again I would require an explanation of the logic in that statement as I see none.
I will agree that the more one flies the more he will appreciate finer resolution in SOME planes, but not all people. Some people just blast holes in the sky and couldn't care less about precision.
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From: Lincoln,
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Me thinks CGRetired probably knows his stuff, but clicked "OK" before a good once over.
Reducing ATV or End Points obviously reduces servo resolution. It also reduces effective torque to control surface. Both are bad. For this reason, you should always try to resolve throw issues mechanically, not by reducing ATV/Endpoints.
Precision is obviously precision based. CGRetired's post does state this... maybe a better order would have been "If precision (pattern) is not an issue"
You can lose some precision by using the innermost hole on a servo on a bad setup. If there is slop in the linkage at the servo side, it will translate to lack of precision at the control surface. This is exergrated on inner servo arm holes. This is however a very small effect, is probably only noticed by us pattern freaks, and can be resolved with ball links, so I would't worry too much about that.
Reducing ATV or End Points obviously reduces servo resolution. It also reduces effective torque to control surface. Both are bad. For this reason, you should always try to resolve throw issues mechanically, not by reducing ATV/Endpoints.
Precision is obviously precision based. CGRetired's post does state this... maybe a better order would have been "If precision (pattern) is not an issue"
You can lose some precision by using the innermost hole on a servo on a bad setup. If there is slop in the linkage at the servo side, it will translate to lack of precision at the control surface. This is exergrated on inner servo arm holes. This is however a very small effect, is probably only noticed by us pattern freaks, and can be resolved with ball links, so I would't worry too much about that.
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From: , MD,
Ok, that makes sense. So the idea is if you move the rods to the inner holes, the effects of "slop" in the system become more pronounced. The ultimate effect is a lack of precision.
So is there a "best" way to adjust the system? For instance, do you try to keep the outtermost servo hole? Thanks again.
So is there a "best" way to adjust the system? For instance, do you try to keep the outtermost servo hole? Thanks again.
#9
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ORIGINAL: anthof
So is there a "best" way to adjust the system? For instance, do you try to keep the outtermost servo hole? Thanks again.
So is there a "best" way to adjust the system? For instance, do you try to keep the outtermost servo hole? Thanks again.
The initial "servo inboard/control horn outboard" concept is entirely correct -- but there are compromises required for everything. Keep your control throw minimization to a minimum

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From: Rochester,
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To summarize: if you want to reduce throw and you have the choice of moving out on the horn or in on the servo arm, you move out on the horn to reduce slop. If that's not enough reduction well, changing holes in the arm won't introduce *that* much slop anyway : )



