Seal off ebay

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Steven88

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hello, the instructions for my Perfect Flight altimeter say it’s a good idea to seal off the bulkheads, with an o-ring or silicone, from the ebay tube to keep the ejection charge gasses from reaching the altimeter inside the ebay. Is this a necessary procedure? I did put silicone into the hole that my wires pass through in the bulkheads to keep gasses out of there. Thanks for any advice you have.
 
Not required, but I always see spikes in the data when the charges go off. One, maybe two data points at each event. Sealing the avbay might help. This is the data plot from a Stratologger on a dual deploy flight.

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You don’t have to, but then your ebay will get gunked up eventually. Cheap fix though- get some poster tack and use it to plug the hole from the outside...
 
You don’t have to, but then your ebay will get gunked up eventually. Cheap fix though- get some poster tack and use it to plug the hole from the outside...

The “gunk” becomes an issue, particularly because BP is corrosive. If you want your electronics to last, try your best to keep ejection charges out.
 
It depends on what materials are being used. I'm suspicious of O-rings and plywood because I don't think the O-rings will deform into the grain. Maybe with fiberglass parts and perfect fitting an O-ring would work.

Silicone could work, but that would be a big mess when you open it up.

I do use silicone or poster tack to cover the holes where the e-match wire comes through the bulkhead.
 
Tim's right, look for the poster display and there'll usually be some hanging on a strip or small shelf right there.

Any thoughts on a line of thin masking tape along the inner wall of the E-bay where the lid seats?
 
In general, I do not seal my ebays. I will use poster adhesive putty to seal around wires if there is a gap between them and the wires to the ejection charges.
 
I never "seal" the AV bay lids. All lids are stepped, and I seal the holes where the wires go through with 1" wide masking tape. Never get any residue into my electronics.
 
Dollar Tree has poster tack for a buck. Same as the stuff costing several times more.

While I'm on the subject, their pack of disposable nail files are great for sanding slots or small details. 1$
 
My 4" av-bay has wooden end caps with a LOC tube coupler. 5 min. Epoxy was used where the wires pass through to the terminal blocks. I never used anything to seal the caps to the coupler. It's ten years old and has 50 flights on it. Still using the original altimeter and never had an issue with gases or corrosion from the charges.
 
I would highly recommend the Loc-tite for a bit more cost.....if you fly where it is hot.
I used the cheap stuff and it melted in the sun, ran down between coupler and airframe gluing them together. Luckily found out before flight, still had to bang out the coupler/av-bay with pipe through motor mount...it was ugly.

What was left in package melted and ran all over everything in my tool box.
 
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