What designs have you used or seen used for keeping piano hinge pins in place until you want to remove them. The hinges are fiberglass, either with or without brass tube bushings and have very modest working spaces around them. We have already beaten the topic of hinge and pin materials to death elsewhere. Let's please stick to retaining hinge pins in the composite hinges.
Fairing and Trim Tabs use 3/32 passivated stainless hinge pin. I have a couple ways that might work. Please educate me on if each concept is suitable, what is right and wrong about them, what needs doing etc:
Billski
Fairing and Trim Tabs use 3/32 passivated stainless hinge pin. I have a couple ways that might work. Please educate me on if each concept is suitable, what is right and wrong about them, what needs doing etc:
- Putting a simple 90 degree bend in one end, rotating the tab into little slot, and then gluing it with clear silicone sealer - no redundancy. See Sketch A;
- Bend a detent bump in the wire and cut a recess in a nearby structure for it to slip into. I am thinking most likely putting this on a U bend in the wire. Redundant retention is available by gluing it in with clear silicone sealer. See Sketch B;
- 1/8" passivated stainless pin or a 3/16" Torlon pin.
- Both are marginally big enough to drill and safety wire;
- Both are big enough to thread and put on a nut;
- I can bend the stainless and retain it in a slot with silicone sealer;
- I can cross drill the Torlon, put in a cross wire, and retain in a slot with silicone sealer.
- The obvious "bend the end of the pin" approach is undesirable for reasons of damaging the hinges and paint during removal - low priority;
- Bending a U shape pin with a springy retention feature that engages a slot. Might be OK on some fairings as they are away from antennas. To give it enough springiness for retention to work and not to yield the pin everytime you remove it, it gets up into the overall length that cause it to detune the antennas, so won't work well in the trim tabs and rudder. See Sketch C;
- 0.093" wire is darn tough to drill and safety wire adequately;
- Threading 0.093" wire for #2 nuts - little teeny nuts and threads.
Billski
