Adding Pushrods to Biplane Ailerons
11-11-2008, 07:33 PM
#1
Adding Pushrods to Biplane Ailerons
I want to add scale aileron pushrods to a biplane designed to use four wing servos for the ailerons. I'm going to delete the top servos and install a pushrod.
I know there are some geometric issues with the setup. So if someone who has done it can provide some tips that would be great. I also wondering if I can use regular control horns or if someone makes horns that help get the angles and distances right. thanks.
I know there are some geometric issues with the setup. So if someone who has done it can provide some tips that would be great. I also wondering if I can use regular control horns or if someone makes horns that help get the angles and distances right. thanks.
11-11-2008, 11:18 PM
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RE: Adding Pushrods to Biplane Ailerons
A larger birds need more power from the servo to control 2 ailerons i was hoping you were doing it to a smaller bird
11-12-2008, 10:54 AM
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RE: Adding Pushrods to Biplane Ailerons
You might take a look at this string: http://www.rcuniverse.com/forum/m_79...tm.htm#7965041
I have discussed this with some others and they seem to think it isn't essential that the geometry is perfect. I have decided to go with 4 servos on my bipe..............
I have discussed this with some others and they seem to think it isn't essential that the geometry is perfect. I have decided to go with 4 servos on my bipe..............
11-13-2008, 04:00 AM
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RE: Adding Pushrods to Biplane Ailerons
Spais,
Two reasons for four servos: 1) you need the power with a large, fast, higher aerobatic bird; 2) you firm up the control linkage on the aileron that would have been controls by the pushrod, thus reducing the chance for flutter. A side benefit is that the impact of a lost servo is reduced by half.
The best way to get the geometry right in a pushrod controlled installation is to connect the pushrod at the same vertical position on both top and bottom ailerons. That is, if the connector pin is above the trailing edge on the bottom aileron, then the connector pin needs to be equally above the trailing edge on the top aileron. After that, the geometry pretty much controls itself.
Have fun!
Bedford
Two reasons for four servos: 1) you need the power with a large, fast, higher aerobatic bird; 2) you firm up the control linkage on the aileron that would have been controls by the pushrod, thus reducing the chance for flutter. A side benefit is that the impact of a lost servo is reduced by half.
The best way to get the geometry right in a pushrod controlled installation is to connect the pushrod at the same vertical position on both top and bottom ailerons. That is, if the connector pin is above the trailing edge on the bottom aileron, then the connector pin needs to be equally above the trailing edge on the top aileron. After that, the geometry pretty much controls itself.
Have fun!
Bedford
