Convert Millimeters to Degrees
#1
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My Feedback: (15)
Need some help converting millimeter throw to degrees. What do you guy's do
example Ailiron state 20mm up/ 20mm down
Elevator state 8 mm up / 12mm dowm
Rudder state 30 L / 30mm R
How do you convert the throws, do you use a rule or is there a throw meter that reads in millimeters
Thanks For the help
example Ailiron state 20mm up/ 20mm down
Elevator state 8 mm up / 12mm dowm
Rudder state 30 L / 30mm R
How do you convert the throws, do you use a rule or is there a throw meter that reads in millimeters
Thanks For the help
#3
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From: Perth, AUSTRALIA
deflections in millimetres are control surface dependant. If you want to convert it to degrees you need to know the length of the surface and then use your trig to figure out the degrees.
I just use a deflection meter with millimetres, of if you have one in inches, divide the mm by 25.4 to get inches.
I just use a deflection meter with millimetres, of if you have one in inches, divide the mm by 25.4 to get inches.
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From: Moss, NORWAY
You need to divide the throw (eg. 20mm) by the chord of the aileron (eg. 80mm) and take the inv. sin to that number.
(e,g, 20/80=0.25 sin-1 0.25=14 deg.)
Magne
(e,g, 20/80=0.25 sin-1 0.25=14 deg.)
Magne
#5

Try this on the NSRCA website.
http://nsrca.us/index.php?option=com...ding&Itemid=95
It is something I made by modifying the one from aero-perfect.
It should do what you want.
Stuart C.
http://nsrca.us/index.php?option=com...ding&Itemid=95
It is something I made by modifying the one from aero-perfect.
It should do what you want.
Stuart C.
#6
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From: Nivaa, DENMARK
Hi Jarvis,
I have done a few examples, the way I learned it. Its pretty much the same as Magne showed you.
Best regards
Michael Gibson
I have done a few examples, the way I learned it. Its pretty much the same as Magne showed you.
Best regards
Michael Gibson
#8

My Feedback: (8)
Eyeball it, then use your gage to make sure throws are consistent (ailerons same, elevator same, etc). Numbers in the manual are a reference, you will most likely end up changing the throws to your liking. Common start points are 10deg ail/ele and 45 (I think) for rudder. I used to try the conversions and use numbers, but after making changes I got tired of keeping track and doing math.
The throws on my Wind are so far below the recommendations in the manual, maybe 7 degrees now. If you have dual/triple rates, you can do something like 5deg, 10deg, and 15deg. Takeoff at 10 and switch if needed.
The throws on my Wind are so far below the recommendations in the manual, maybe 7 degrees now. If you have dual/triple rates, you can do something like 5deg, 10deg, and 15deg. Takeoff at 10 and switch if needed.
#9

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From: North Las VegasNV
ORIGINAL: Magne
You need to divide the throw (eg. 20mm) by the chord of the aileron (eg. 80mm) and take the inv. sin to that number.
(e,g, 20/80=0.25 sin-1 0.25=14 deg.)
Magne
You need to divide the throw (eg. 20mm) by the chord of the aileron (eg. 80mm) and take the inv. sin to that number.
(e,g, 20/80=0.25 sin-1 0.25=14 deg.)
Magne
#10

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From: Mt. Pleasant,
OH
I do that sort of thing graphically. I draw the control surfaces and suggested throws full size and measure the result with a protractor.
But then, I'm mathematically dyslexic, lol.
Scott
But then, I'm mathematically dyslexic, lol.
Scott
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From: Jonkoping, SWEDEN
Google can do the calculations for you. Enter:
180/pi*arcsin(deflection/chord)
in the search field using the same units for the deflection and control surface chord.
Example:
180/pi*arcsin(20/50) = 23,6 degrees.
180/pi*arcsin(deflection/chord)
in the search field using the same units for the deflection and control surface chord.
Example:
180/pi*arcsin(20/50) = 23,6 degrees.
#14

My Feedback: (1)
Man, this is making a mountain out of a mole hill. This is not rocket science, folks.
The deflection in mm is denoted for that specific model and is measured at the trailing edge as noted above by Rendegade.
Joe also makes a good point because this is just a starting point for any control surface and will, most likely, be changed by the owner to suite his/her needs.
If it says Ailiron 20mm up/ 20mm down, well, measure that at the trailing edge. Who cares what the degrees of throw is at that point. Set it up and fly it. If you don't like it, change it. Then measure it and figure it out if that floats your boat. Arcsin(deflection/chord)? If you have had Trig, then that's alright. If not, then what's an arcsin?
CGr.
The deflection in mm is denoted for that specific model and is measured at the trailing edge as noted above by Rendegade.
Joe also makes a good point because this is just a starting point for any control surface and will, most likely, be changed by the owner to suite his/her needs.
If it says Ailiron 20mm up/ 20mm down, well, measure that at the trailing edge. Who cares what the degrees of throw is at that point. Set it up and fly it. If you don't like it, change it. Then measure it and figure it out if that floats your boat. Arcsin(deflection/chord)? If you have had Trig, then that's alright. If not, then what's an arcsin?
CGr.
#16
Senior Member
ORIGINAL: CGRetired
Man, this is making a mountain out of a mole hill. This is not rocket science, folks.
The deflection in mm is denoted for that specific model and is measured at the trailing edge as noted above by Rendegade.
Joe also makes a good point because this is just a starting point for any control surface and will, most likely, be changed by the owner to suite his/her needs.
If it says Ailiron 20mm up/ 20mm down, well, measure that at the trailing edge. Who cares what the degrees of throw is at that point. Set it up and fly it. If you don't like it, change it. Then measure it and figure it out if that floats your boat. Arcsin(deflection/chord)? If you have had Trig, then that's alright. If not, then what's an arcsin?
CGr.
Man, this is making a mountain out of a mole hill. This is not rocket science, folks.
The deflection in mm is denoted for that specific model and is measured at the trailing edge as noted above by Rendegade.
Joe also makes a good point because this is just a starting point for any control surface and will, most likely, be changed by the owner to suite his/her needs.
If it says Ailiron 20mm up/ 20mm down, well, measure that at the trailing edge. Who cares what the degrees of throw is at that point. Set it up and fly it. If you don't like it, change it. Then measure it and figure it out if that floats your boat. Arcsin(deflection/chord)? If you have had Trig, then that's alright. If not, then what's an arcsin?
CGr.
He, he, devil made me do it; couldn't resist
#21
Bah!!!! I just set everything to maximun throws, then set dual rates to half that, then fly it and back off settings till it flies like I want it too
Since yours is in mm's, I assume its a ....not built in USA....kit or arf[:-] Those guys are too anal about stuff like that. Do it the good old American way, by the seat of your paints
Since yours is in mm's, I assume its a ....not built in USA....kit or arf[:-] Those guys are too anal about stuff like that. Do it the good old American way, by the seat of your paints
#22
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From: Columbus,
OH
Don't worry about the what the manufacturer says as far as surface deflection in mm or inches. Set ailerons, elevator and rudder to full defection (before the surface begins to bind) when at high rates. Then set low rates at about 15 deg for ailerons and 15 deg for elevator. Use 50% or more expo when on high rates. Use 25% or lower when on low rates. I make the rudder deflection for high and low rate to be the same. I use about 50% expo on rudder. Fly the plane then adjust the rates and expo to soot your personal preference.
#24
ORIGINAL: Columbus Ron
Don't worry about the what the manufacturer says as far as surface deflection in mm or inches. Set ailerons, elevator and rudder to full defection (before the surface begins to bind) when at high rates. Then set low rates at about 15 deg for ailerons and 15 deg for elevator. Use 50% or more expo when on high rates. Use 25% or lower when on low rates. I make the rudder deflection for high and low rate to be the same. I use about 50% expo on rudder. Fly the plane then adjust the rates and expo to soot your personal preference.
Don't worry about the what the manufacturer says as far as surface deflection in mm or inches. Set ailerons, elevator and rudder to full defection (before the surface begins to bind) when at high rates. Then set low rates at about 15 deg for ailerons and 15 deg for elevator. Use 50% or more expo when on high rates. Use 25% or lower when on low rates. I make the rudder deflection for high and low rate to be the same. I use about 50% expo on rudder. Fly the plane then adjust the rates and expo to soot your personal preference.
LOL more or less what I just said

WBG
#25

My Feedback: (3)
I agree with CGRetired! Talk about making rocket science that is not necessary. Just measure the throw at the outboard tip (or inboard tip if specified) of the trailing edge of each control surface directly with a ruler in mm.
Of course you can use trigonometry to get to degrees using the surface chord length but why complicate things?
Of course you can use trigonometry to get to degrees using the surface chord length but why complicate things?


