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Silicone recommendation

AboveMSL

Well Known Member
I'm at the stage of preparing the elevator pitch trim harness. The instructions have you apply silicone to one end of the harness. I have no experience with this type of work and I'm wondering what type of silicone to use......which makes me wonder if there is more than one type of silicone. What have you other 14 builders been using here. Thanks,

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Momentive RTV 162 or RTV 6708 are good choices.
You want an electronics grade, not acidic cure bathroom type sealant.
At least that would be my advice. If in doubt, call Van's.
 
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alternative to Molex

Deutsch connectors are resistant to water at 3ft depth. I haven't tested it. I used the gold plated pins. These are same connectors under the hood of your car. If you use the connector base as in the picture, I recommend grinding off the plastic latch lock so that is it a friction dovetail lock and not a one time forever lock. The grinding takes 2 seconds to complete.

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Alright, so I used GE Premium clear silicone from Home Depot. The plans don't specify anything specific. So I don't see where it would make a difference.

#140100

I made a living around electronics and know the difference between the different silicone that is available.

I, like you, used the CHEAP $3 stuff sold at Home Depot, Lowes, and Pep Boys to use on a Circuit Board to stabilize some capacitors. I did not want to buy the $30 stuff. That was over 18-years ago and the unit is still flying.

The link in this thread is the correct stuff to use but some of us CHEAP guys have used the other stuff that is available locally.
 
Alright, so I used GE Premium clear silicone from Home Depot. The plans don't specify anything specific. So I don't see where it would make a difference.

#140100
for your bedtime reading:
http://www.academia.edu/1902960/Coating_materials_for_electronic_applications_polymers_processes_reliability_testing
page 120:
>>snip
"An originally introduced moisture-cured resin, in which the hydroxyl group was converted to acetoxy, is now seldom used for electronic applications because of the many failures caused by the release of corrosive acetic acid as the by-product. The released acetic acid corroded thin-film metallizations and chromium and cadmium plated parts, especially when confined in a sealed enclosure."
>>>

page 127:
(an interesting property (mildew under the shower caulk anyone?))
>>snip
"Other Properties.

Because of their low surface tension due to hydrocarbon groups appended to the silicon atoms, silicones have low water absorptions and repel water and, as such, are widely used as water repellents in many military and commercial applications. Paradoxically, in spite of their low water absorptions and water repellent properties, silicones have high moisture vapor transmission rates."
>>>

However, I doubt you'll fall out of the sky...well, before that anodized spar cracks or the knife-edge countersinks cause the tanks to fall off...:D
 
... now seldom used for electronic applications because of the many failures caused by the release of corrosive acetic acid as the by-product

I'm just saying that if it was that important then Van's would have identified a specific silicone to use, or put something in the plans like "use electronics grade or aviation grade or mil-spec silicone of the non-acidic variety"

Because they didn't, I take it to mean it's up to the builder to use any silicone they want to seal that connection hanging on the outside of the airplane. It never occurred to me to look for anything other than what the local hardware store sells.

But.......now that there's a few recommendations, I made a note to consider them to seal any other electrical connections that come up during the build.


#140100
 
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