Vibration and Electric Conduit in Wings

dons · Post by **dons** » Sat Oct 27, 2007 12:59 pm

I have been working on my wing ribs for what seems to be months and have put the suggested 0.75" holes in for the conduit like many others. My question has to do with if vibration of the wires within the conduit should be a concern, especially the ones going all the way to the tips. My thought here is that there is no regular securing mechanism as there would be in the case if the wires were clamped at each rib. The parking lot where I work has 35 foot metal lamp poles and a single access plate at the base with no wire clamps until the top mounted fixture (I'm sure several of you know where this is going already). When the wind blows at the right speed and vibrates the pole, the wires slap against the inside of the pole creating quite a racket. My gut feeling is that behavior can't be good for long term reliability and could easily occur inside the wing conduit. The wing conduit is smaller in diameter, is somewhat softer than a metal pole, not as long, but I still think about having long wire runs doing their thing inside there.

I suppose I could open the conduit near one or more of the inspection plates and secure the wires there, but that sorta defeats the purpose of the conduit and doesn't really work for the outboard half of the wing.

Am I worrying about something I shouldn't be ?

Post by **Spike** » Sat Oct 27, 2007 1:16 pm

Hmmm, thousands before have not reported issues. That probably says you are ok.

Personally I think I will be tying the wires into a bundle using string, and then securing with adel clamps or some such. A good friend did this in his 8A and its a very sound installation.

Spike

dons · Post by **dons** » Sat Oct 27, 2007 1:35 pm

I can't say I found any reference to bad things happening in conduit, but after thinking about, I have almost convinced myself I would rather use clamps for the initial build and leave the conduit for any future wire runs that I can't do any other way easily.

svanarts · Post by **svanarts** » Sat Oct 27, 2007 11:28 pm

I used the black corrugated conduit in my RV-4 wings and ran all the wires through that. No issues in 5 years.

dons · Post by **dons** » Wed Oct 31, 2007 3:43 pm

Thanks, I won't lose any sleep over this, I'll find something else to worry about at night, like engine choice, cowl, avionics, interior, etc.

captain_john · Post by **captain_john** » Wed Oct 31, 2007 4:11 pm

Yet another use for our good friend PROSEAL!

I gooped mine in place and won't lose any sleep over it!

CJ