Elevater pushrod failed!
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From: salida,
CO,
Today while flying my push rod separated from the piece of shrink rap holding the two pieces of rod together. They were glued with CA on both ends of the rap and I had a good 20 flights on this plane, but today it failed 100+ feet up. All that is left is the electronics.[:@] I am going to build up another plane, but my question is, does this happen often. What are the other options for control surface rods and horns? Can I solder the rods together? The model was a mountain models smooth-E. Thanks for any suggestions.
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From: Spencerport, NY
If that was how the two ends of the pushrod were fastened together, it was only a matter of time before they slid apart. There's a huge amount of stress on the pushrod, even on small models, and the pushrod needs to be securely fastened by mechanical means. CA does not adhere to metal very well; a slight shock load would pop it loose.
Is that how the instructions told you to install the pushrod?
Pushrods for short runs are generally one piece of steel, with a Z-bend at the servo end and a threaded-on clevis at the other. Longer runs have a few alternatives:
1. Nyrod/Goldenrod - a flexible pushrod material that is run through a well-supported tube. The tube must be supported at regular intervals or the pushrod will just flex when force is applied in the "push" direction.
2. A steel pushrod in a well-supported tube.
3. A spruce, fiberglass, or carbon fiber pushrod, with short lengths of steel pushrod securely fastened to the ends.
Is that how the instructions told you to install the pushrod?
Pushrods for short runs are generally one piece of steel, with a Z-bend at the servo end and a threaded-on clevis at the other. Longer runs have a few alternatives:
1. Nyrod/Goldenrod - a flexible pushrod material that is run through a well-supported tube. The tube must be supported at regular intervals or the pushrod will just flex when force is applied in the "push" direction.
2. A steel pushrod in a well-supported tube.
3. A spruce, fiberglass, or carbon fiber pushrod, with short lengths of steel pushrod securely fastened to the ends.



