I've been flying a H9 US 120(not light) for about two seasons. The beginning of this season, I've had no less than four CA hinges break at the hinge line. These are the hinges that came with the ARF. They have a litlle slot cut in the middle of them. I've had them break on the elevator, aileron and flap. This plane is by no means overpowered(Zenoah G-23). Just wondering if anyone else has experienced this problem with these particular hinges. Thank goodness for the GP slot machine

Marty

How old is the plane? I don't know how long CA hinges last but I believe I would be looking to change them all now.

I would change them too.. I'm using the stock hinges on my US Lite. But I'm sure I'll have to change them out in a few years..

The plane is probably about four years old but wasn't assembled and put into service until about two years ago.

Marty

Use Radio South hvy duty hinges. They are available from Tower, and most LHS. Never had one fail or pull out.
Z

Forgive me if you already know.... but are the hinge lines possibly too tight? I like to leave the pin in place while gluing for a spacer. Did any sharp CA crystals remain on the hinge line that can cut the hinge prematurely? I mark the center of the hinge with a color crayon so the CA won't stick well in the very middle of the hinge, and then take a toothbrush with acetone on it and scrub that center line clean after an hour or so. Another thing that works well is to drill a tiny hole in the center of each slot, and then take a pointed soldering iron and burn a tiny little "funnel" at the entrance to each hole. That way the glue runs right down where you want it to be and doesn't run down the hinge line or gum up the joint so much.

Ernie

Ernie,
You make some very good points on keeping the hinge line area of the hinge "clean" in the sense of not getting to much CA on the line. I don't think that was really the problem . I have other planes twice as old with CA hinges and many more flights that are still good. I feel that something was wrong with the hinges and was trying to see if anyone has had similar issues with these particular hinges. My last few planes i have buitlt, I've been using nylon pinned hinges with epoxy. These seem to me, stronger in addition more free moving and less force needed on the servo.

Marty

Ernie Thanks for the tips