Servo Selection on 40 size 3D?
07-03-2005, 12:07 AM
#1
Servo Selection on 40 size 3D?
Do you guys use standard servos on your 40 size Fun Fly and 3D planes?
I've got a 40 size Giles 3D. It's set up for dual aileron servos and dual elevator servos. Single rudder servo.
I'm using 120oz coreless in the ailerons. 70oz coreless on each elevator. And a 100oz digital coreless on the rudder.
My flying buddy is telling me it's overkill and that standard BB servos with 40-50oz will be fine.
How much torque do the rest of you guys use on a little 40 size 3D plane that weighs 5 pounds RTF?
I've got a 40 size Giles 3D. It's set up for dual aileron servos and dual elevator servos. Single rudder servo.
I'm using 120oz coreless in the ailerons. 70oz coreless on each elevator. And a 100oz digital coreless on the rudder.
My flying buddy is telling me it's overkill and that standard BB servos with 40-50oz will be fine.
How much torque do the rest of you guys use on a little 40 size 3D plane that weighs 5 pounds RTF?
07-03-2005, 01:13 AM
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RE: Servo Selection on 40 size 3D?
Just use standards. You don't need anything more 55oz.
If our running pull-pull on the rudder then you should get a servo with alittle bit more torque. Something like a Hitec HS-625MG. Nothing more.
With your servos that thing will have stupid fast responses and power.
If our running pull-pull on the rudder then you should get a servo with alittle bit more torque. Something like a Hitec HS-625MG. Nothing more.
With your servos that thing will have stupid fast responses and power.
07-03-2005, 01:22 AM
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RE: Servo Selection on 40 size 3D?
WAY overkill. I think any of the .40ish FF type planes fly fine on standard servos like the Futaba 3004 or Hitec 422/425, BB is a nice addition and will be a bit smoother while in operation but mostly will wear longer than non-BB.
The only change I would make would be the rudder servo should be something in the 70 ounce range and that is plently. This really only applies if the rudder is big, like on most of the .40 profiles. You can use a standard on the rudder in these planes but the higher torque servo is better.
I think where most guys screw up is in the linkage set-up when using standards. With the lower torque servos you should pay particular attention to the servo arm length, surface horn length and how you connect these together. In general you should try to keep the arms short or connect the linkage as close to the pivot on the servo as possible to maximize torque. Likewise, the opposite applies at the surfaces, keep the clevis connected as far away from the hingeline as you can.
More often than not these smaller planes fly better with lower throw/maximized for torque and leverage than with huge surface throws and a very low leverage. You should apply this on ALL of the flight surfaces.
The only change I would make would be the rudder servo should be something in the 70 ounce range and that is plently. This really only applies if the rudder is big, like on most of the .40 profiles. You can use a standard on the rudder in these planes but the higher torque servo is better.
I think where most guys screw up is in the linkage set-up when using standards. With the lower torque servos you should pay particular attention to the servo arm length, surface horn length and how you connect these together. In general you should try to keep the arms short or connect the linkage as close to the pivot on the servo as possible to maximize torque. Likewise, the opposite applies at the surfaces, keep the clevis connected as far away from the hingeline as you can.
More often than not these smaller planes fly better with lower throw/maximized for torque and leverage than with huge surface throws and a very low leverage. You should apply this on ALL of the flight surfaces.
07-03-2005, 07:43 AM
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RE: Servo Selection on 40 size 3D?
ORIGINAL: Shogun
WAY overkill. I think any of the .40ish FF type planes fly fine on standard servos like the Futaba 3004 or Hitec 422/425, BB is a nice addition and will be a bit smoother while in operation but mostly will wear longer than non-BB.
The only change I would make would be the rudder servo should be something in the 70 ounce range and that is plently. This really only applies if the rudder is big, like on most of the .40 profiles. You can use a standard on the rudder in these planes but the higher torque servo is better.
I think where most guys screw up is in the linkage set-up when using standards. With the lower torque servos you should pay particular attention to the servo arm length, surface horn length and how you connect these together. In general you should try to keep the arms short or connect the linkage as close to the pivot on the servo as possible to maximize torque. Likewise, the opposite applies at the surfaces, keep the clevis connected as far away from the hingeline as you can.
More often than not these smaller planes fly better with lower throw/maximized for torque and leverage than with huge surface throws and a very low leverage. You should apply this on ALL of the flight surfaces.
WAY overkill. I think any of the .40ish FF type planes fly fine on standard servos like the Futaba 3004 or Hitec 422/425, BB is a nice addition and will be a bit smoother while in operation but mostly will wear longer than non-BB.
The only change I would make would be the rudder servo should be something in the 70 ounce range and that is plently. This really only applies if the rudder is big, like on most of the .40 profiles. You can use a standard on the rudder in these planes but the higher torque servo is better.
I think where most guys screw up is in the linkage set-up when using standards. With the lower torque servos you should pay particular attention to the servo arm length, surface horn length and how you connect these together. In general you should try to keep the arms short or connect the linkage as close to the pivot on the servo as possible to maximize torque. Likewise, the opposite applies at the surfaces, keep the clevis connected as far away from the hingeline as you can.
More often than not these smaller planes fly better with lower throw/maximized for torque and leverage than with huge surface throws and a very low leverage. You should apply this on ALL of the flight surfaces.
You are saying that the smaller planes do not need as much control throw to get them to 3D well ( say 30° on elevator instead of 50° needed on a larger plane )?
07-03-2005, 02:05 PM
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RE: Servo Selection on 40 size 3D?
Ooops, that's not what I meant. More throw is better, IF you can get it and not loose all of the servo's torque. In the event you have high throws set up and the plane doesn't fly with any authority try changing your set up as described above using the the arms/horns, often the plane will pep up and fly closer to the way the owner desires, even though the throws are lower.
I found that I liked 35 degrees on the elevator of my OMP 540FF much better than 50 for most maneuvers, the only exception being waterfalls and elevators.
I found that I liked 35 degrees on the elevator of my OMP 540FF much better than 50 for most maneuvers, the only exception being waterfalls and elevators.
07-04-2005, 01:35 PM
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RE: Servo Selection on 40 size 3D?
If a Airtronics 102 or Futaba 3003 can fly a 72" aerobatic plane (easy flying) then what do you think of it on a small 40 sized 3D plane? I have used the 'basic' servos on 3D planes, no issues BUT if you fly them really hard, best to go with karbonite/MG ones. Its much safer as the gear might not only break, it can at times skip a tooth, happened to one of my pals on his CG Matrix.
07-04-2005, 03:36 PM
#8
RE: Servo Selection on 40 size 3D?
Thanks guys.
I have 6 NIB HS-425BB servos. But I can't use them on the tail of this plane. It's too skinny to stack 2 standard servos for the elevators. I thought about buying a couple HS-77BB, but I've got a couple mid size JR servos already here--so I'll stick them in the tail for the elevators.
I could use 2 of the 425BB for the ailerons. I'd like to use my 120oz. coreless servos in a larger plane if I can get away with just using the 425BB on my ailerons.
I have 6 NIB HS-425BB servos. But I can't use them on the tail of this plane. It's too skinny to stack 2 standard servos for the elevators. I thought about buying a couple HS-77BB, but I've got a couple mid size JR servos already here--so I'll stick them in the tail for the elevators.
I could use 2 of the 425BB for the ailerons. I'd like to use my 120oz. coreless servos in a larger plane if I can get away with just using the 425BB on my ailerons.
07-04-2005, 08:18 PM
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RE: Servo Selection on 40 size 3D?
ORIGINAL: Shogun
I found that I liked 35 degrees on the elevator of my OMP 540FF much better than 50 for most maneuvers, the only exception being waterfalls and elevators.
I found that I liked 35 degrees on the elevator of my OMP 540FF much better than 50 for most maneuvers, the only exception being waterfalls and elevators.
