ETLB Squawk Forums — Archive

I'm scratch building my Max 1500 and was wondering about the piano hinge used for rudder assembly. I should probably just buy it from TEAM as I'd like to give them some support, but I also have inexpensive access to the proper sized hinge in 1008 cold rolled steel. Any issues with just going with this? I'd assume treat it first to ward off corrosion.

Also, any concern about the pin working its way out? I've found no instructions on treating the pins after cutting the hinge to ensure it is secured and won't "fall out" at some point (I imagine it would be a pre-flight checklist item to inspect).

Thanks.

I like to support Dave as much as possible. He is always there to support us. Personally I would purchase from him. That being said once the hinges are cut . You remove the pin. Then replace it with a hinge pin that is drilled for an cotter pin. Also available from Dave. No way it’s coming out. Also Cold rolled steel will rust and ruin your finish. I believe my factory supplied hinge material was stainless steel.
B-👍👍

I agree; that seems the best option all the way around. I'll just order from Dave.

I would go with the recommendations, that hinge is laid into cut out grooves and once there it needs to stay corrosion free. I primer every piece of metal on my plane with zink primer to prevent corrosion. Unless its the same thing , the piano hinge may be stainless, make sure its heavy duty enough for that application, remember any joint of motion is a potential fail point, I wouldn't drive a car with a thread rod for a steering rod and a car can stop on the side of the road, there is zero room for error in the air.

I built a John Monnet designed Monerai (see my avatar). He recommended a 90 degree bend in the hinge pin rod on one end. The bend was safety wired to the structure, very simple and lite. That said, Monnet's hinges were rolled and the individual hinge  rolls were not welded. Real aircraft hinges were extruded or welded. Probably not necessary on an ultralight. See:

https://www.google.com/search?.....mgrc=mbAO-0-qT4eWZM:

to see how the wing sections are attached to the spar on a Beechcraft Bonanza. You really don't want these to unroll at the hinge point.

Joe

Thanks!