thermal grease, non-electrically conductive and waterproof?

[Admin]

I'm looking for a non-electrically conductive waterproof goop with high thermal conductivity.

Sort of a cross between thermal grease (thermally conductive) and RTV (waterproof and electrically conductive) . . .

Anyone know of something I can use?

[JonHylands]

I use a tube of stuff I picked up at Radio Shack in the US - "Archer Professional Lube Gel".

Its clear, and has "SYNCOLON (PTFE)"

Seems to work pretty well, although I don't know how thermally conductive it is...



- Jon

[Admin]

I need something much more viscous than that lube.

I've been reading a lot on this, and it appears some RTV types can be thermally conductive. But also some types corrode metals and can damage electronics . . . Ill keep looking . . .

[JonHylands]

Its pretty viscous already - I use it to seal the o-rings on my sub.

It comes out of the tube with about the same viscosity as a normal grease you would use on bearings.

- Jon

[ed1380]

how water proof and how much of it do you need?

maybe arctic silver ceramique will work

I know it's one of the best TIM's (thermal interface material)and does not conduct electricity. dunno about waterproofness

[Admin]

how water proof and how much of it do you need?

I need about ~3oz per robot fish, and waterproof meaning it doesn't dissolve, mix with, or liquefy in water.

I decided to order two types of RTV to test out.

[Robotboy86]

I assume you want to coat your PCB/various electronics in this?

I found this a while ago..

http://www.insulcast.com/itwproduct.html

I couldn't find more info at the time, but maybe you can.  They show a few PCB's on there page and its epoxy based so it should resist water..

[Admin]

thanks Robotboy86!

I called that company up and spoke with an engineer who knew his stuff.

Apparently ALL epoxies and silicones are electrically insulating, but there are many different types with many different additives that determine thermal conductivity. (I learn something every day)

He selected a material for me and even said he will send me samples to try out

[Robotboy86]

Let me know how it works out.. it might be worth coating some of my stuff in it once its complete just incase I develop leaks when it rains or something