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That 120 degree hose clamp rule blew my mind last night
I was reading through some old A&P study material my buddy left in the hangar and saw this thing about clocking hose clamps at 120 degrees for fluid lines. I always just slapped them on wherever they landed. Turns out that's a huge no-go if you want even pressure distribution and no leaks. I messed up a gear door line a few weeks ago and now I'm wondering if that's why it seeped. Has anyone else run into this causing weird issues later on?
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ray13629d ago
Man that's exactly what got me a few years back too! I had a brake line on a Cessna that kept weeping no matter how tight I got the clamp, and someone finally pointed out I had all three clamps lined up at the same clock position torquing the hose unevenly. Swapped them to 120 degrees apart and the seep stopped completely so yeah it definitely matters on fluid lines.
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the_nathan28d ago
Man that's a pain when something simple like that causes issues!
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anthony_campbell8828d ago
I actually read somewhere that some old school guys call it the three thumb rule, where you space them about a thumb width apart and that ends up close to 120 degrees. It's one of those things that sounds too simple to matter but apparently it's been a known issue for decades in high vibe environments. Makes me think I need to go back and recheck a few of my own clamps this weekend.
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