RCU Forums - View Single Post - Lets talk about control Rods, what are you using, what works, what dont work??
Old 08-03-2015, 04:34 PM
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roger.alli
 
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Originally Posted by mr_matt
The only advantage of titanium here is weight, it is no stronger than steel just lighter. So unless this is some physically larger replacement pushrod I don't see how these titanium rods are any stronger, just more $$$ kind of like kevlar fuel tanks :-)



Flex? I have used carbon fiber pushrods for years and they were bulletproof, mine were Central Hobbies like "Instructor" explained,

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Agree with you here Matt. CF rods are stiffer than any metal, including titanium. CF really comes into its own when using long rods. I recall using CF arrow shafts in gliders with push rods over 24" long.. These shafts are thin wall aluminium tube about 3/8" dia, with a wrap of CF around it. Much less prone to bending under compression than metal or wood rods.. Interestingly, the next best rod material, was a length of 1/2" square section balsa wood. Remember those days..

Flutter is a complex problem involving, among other things, the elasticity of the entire airofoil structure stiffness, and control surface support systems. Control rods are one small part of the system, but I would be surprised if the rod material choice would add much to the elasticity of the system. Especially with very short rods like the Avanti use on Elevator..