verslagen1 wrote on 11/15/12 at 15:16:11:

Since when verslagen?  Most epoxies is basically just a plastic.  Epoxies have been used for years for potting electronics to seal them from moisture and vibration.

I have used most kinds of off the shelf 2 part epoxies for sealing electronics through the years without any issues at all.  Remember we are talking about epoxy and not something like JB weld or that steel putty or any metallic containing adhesives.  Just a plain ordinary clear UV resistant epoxy.

R.F.

T-88 aircraft epoxy is really tough stuff, sticks to just about any roughened surface, and never gets brittle (stays flexible).  I've used it for years and have never seen it ever get brittle or deteriorate at all.  I used it on the Double RYCA build, and I have used it in many places on the gyrocopters I build.
  -- It sets up slowly.
      --- The good news is you have a lot of time to phart around with the joint.  
      --- The bad news is you'd better not be in a hurry.  It takes a few hours to get firm, and a day to get hard and usable.  It keeps getting stronger for a few more days.
  -- It won't shrink.
  -- It will hold up to temporary gas spills, but it is not suitable for use on gas tanks or other situations that have continual exposure to gas.

http://www.systemthree.com/store/pc/T-88-c27.htm

SALB wrote on 11/15/12 at 16:13:39:


SA,

That's a possibility!

Thanks!

Most of the epoxies I tend to fall back to are the air hardening type used for fiber glassing.  The 2 main places I buy online are from fiberglast.com and http://www.uscomposites.com/   Just make sure you get the type that is specified for air hardening and not layering or it will never harden up on you.  The layering epoxies are intended for use in vacuum bagging type techniques.

A google search that will help you out greatly is to search for a potting epoxy.  You will come up with lots of options out there. Ranging from Urethane based systems to real epoxy systems that will cure from a gel like texture to a rock hard like texture.  The biggest benefit of the softer gel cured ones is that it's easier to remove the potting from your electronics should you ever have to service them, where as if you use the hard cure epoxies your better off just doing a total rebuild should something fail.

I have potted with epoxies this using the standard fiber glassing epoxies on projects from low voltage/low current all the way up to high voltage/high current projects and have had no shorts in the potted areas.  In a pinch I have also used the exterior grade 2 part epoxies from the local hobby shops and home supply stores such as Lowe's and Home depot and have had similar results.   Just make sure you use the epoxy and not the polyester resins for doing your potting. While I'm fairly sure the polyester resins will work I've just never used them and can't vouch for how they may react with plastics.  If you do the search for potting epoxies you will come across alot of them that are certified for use by NASA which should tell you something right there on how well epoxies do for insulating and protecting electronic circuits in the most extreme of circumstances.

R.F.

So many options. Easily removable? Rubber cement. Semi-permanent? Caulk or RTV. Permanent? Liquid Nails, Epoxy, hobby cement - the list is almost endless.

P.S.
Liquid Nails is slightly flexible when dry so if there needs to be some give that won't rip free like RTV or caulk or every other silicone based sealant, that would be a good choice.

If weight is no matter, or if you could slip another piece of pipe inside to fill most of the void, then drill a hole on each end & pump it full of silicone.

Cavi Mike wrote on 11/16/12 at 01:54:47:



Thanks, Cavi.

I'm thinkin' about going with Marine Goop, thinned with some toluene (if I can find it).  I've already got the Marine Goop.....