Servo choice for profile rebuild
#1
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Servo choice for profile rebuild
Im in the process of rebuilding my OMP Proyak that I live. Originally I had Hitec 311 on Elevator and ailerons, and Hitec 635 on rudder. As I was reinstalling the servos in the fuse, I realized I have a bunch of Hitec 5475s laying around. Would the 5475s be better for low and slow? They have more torque however as per specs are a slower servo. What do you guys think?
HS 311 Specs
Operating Speed (6.0V): 0.15sec/60° at no load
Stall Torque (6.0V): 51 oz/in (3.7 kg/cm)
Hitec 5475 specs
Operating Speed (6.0V): 0.18sec/60° at no load
Stall Torque (6.0V): 76 oz/in. (6.4kg.cm)
HS 311 Specs
Operating Speed (6.0V): 0.15sec/60° at no load
Stall Torque (6.0V): 51 oz/in (3.7 kg/cm)
Hitec 5475 specs
Operating Speed (6.0V): 0.18sec/60° at no load
Stall Torque (6.0V): 76 oz/in. (6.4kg.cm)
#3
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Personally I'd go with the 5475's, more torque is better and I'm not so sure the difference of .03 seconds is going to be noticeable. Plus you can make them faster (while gaining) more throw just by moving the controll rod further out on the servo arm. Higher torque servos can handle that better.
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no you can't if a servo takes .13 mills to move 90 degree I don't understand what your going to do to make it move faster then that other then whats outside the servos specs
its really not going to matter your fun fly 3d profile here I think you'll be alright 99 % of the pilots can't out fly a modern servos speed
and only place I really feel sevro speed it is Flying a heli .. with collective movement from positive to negative . and airplane is really Rudder while doing rollers and trying to turn the plane going from Right medium throw to Left medium throw .. if you get behind with the rudder it's a lot harder to keep your AOA
what I am really getting at is I don't think you'll be dispointed either way ..
its going to be hard to do rifle rollers and High speed engry stuff with that profile.. let alone if you can even do rifle rollers where you need servo speed..
the short couple giant wing on that thing its not going to even snap fast or roll vary straight normaly they have a lot of coupling and some funky quarks doesn't make them a bad airplane it just isn't the same thing as other airplanes what it does make them is a good floatly easy to fly 3D plane like a big Foamy ... and you don't need blazing speed on a big foamy same as you don't need blazing speed of profiles
Last edited by zacharyR; 09-04-2013 at 07:16 PM.
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dude how's it going to move faster then the servos movment ? if the servo moves at .13 90 degree the surfcace is going to move the same speed
you can change the amount of surface deflection and the toruqe factor with moveing the control rod's placement on the Surfaces control horn ..
for example the time it takes the servo to move 90 degree's from the center point or whatever is going to be same time that the surfce moves from a center point to max end point .. yes you can change the distance or degree of delfection ..
you can change the amount of surface deflection and the toruqe factor with moveing the control rod's placement on the Surfaces control horn ..
for example the time it takes the servo to move 90 degree's from the center point or whatever is going to be same time that the surfce moves from a center point to max end point .. yes you can change the distance or degree of delfection ..
Last edited by zacharyR; 09-05-2013 at 12:52 PM.
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Zach, the speed of the servo is constant ,Yes. But the farther away from the center of rotation the faster the movement. Lets say you put the clevis in the first hole off of the servo, it will move a distance of appr 1/4". But the farthest hole out will give movement of appr 1-1/2". Now these two movement measurements are at the same servo speed but the distance the two traveled in that time is no where near the same. It's not changing the servo speed, only the speed of the linkage by the distance of the servo horn clevis travel. And also by doing this it is likely that the endpoint will have to be shortened. Which in a sense shortens the time required for that movement, which in turn, does make it faster in time.
Last edited by acerc; 09-05-2013 at 06:44 PM.
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Zach, just think of a front sprocket on a mtn bike: for the same driveshaft speed (pedal crank on bike; output splines on servo), the farther out you go, the more distance and the faster the speed, if everything else stays the same--just shifting into a higher gear. You lose torque but gain speed.
In any event, I think Zach's right: I've been using Hitec 5485's on a couple different profiles for some time now, except for using a mg servo on the rudder, and they work fine. Actually, a lot of profile guys use mg mini's on the ailerons and elevator for .40 size profiles. Something like a Hitec 5245, Spektrum A5040, or Solar D658, for cheaper options.
In any event, I think Zach's right: I've been using Hitec 5485's on a couple different profiles for some time now, except for using a mg servo on the rudder, and they work fine. Actually, a lot of profile guys use mg mini's on the ailerons and elevator for .40 size profiles. Something like a Hitec 5245, Spektrum A5040, or Solar D658, for cheaper options.