Question Thermally conductive glue or epoxy.

[rustedmetal]

Has anyone any experience using a thermal glue or alike that's more conductive than 1 W/ mk? All i see when i research is this cheap chinese glue with god awful specs. I can't seem to find a decent thermally conductive epoxy. I need to attach a heat pipe to a heat sink.

 

[hotaru.hino]

If it's metal to metal, you should consider soldering them together.

 

[rustedmetal]

If it's metal to metal, you should consider soldering them together.

I already tried soldering a few heat pipes with low temp solder but only managed to solder one and i don't even know how i did it. It took forever and it was a hassle since i was trying to avoid bursting the pipe, that's why i'm resolving to thermal glue/epoxy.

 

[hotaru.hino]

How exactly are you fitting the heat pipes to the block?

If I were trying to affix heat pipes to a metal block and soldering is out of the question for some reason, then I would use thermal paste or liquid metal between the contact points and epoxy it all to seal it. And just hope it holds.

 

[CountMike]

I already tried soldering a few heat pipes with low temp solder but only managed to solder one and i don't even know how i did it. It took forever and it was a hassle since i was trying to avoid bursting the pipe, that's why i'm resolving to thermal glue/epoxy.

Just use industrial grade liquid/Epoxy metal

Best Metal Epoxy 2021 - The Ultimate Practical Guides for ALL Projects

What is the best metal epoxy? You might be a handyman or a mechanic or just another person with a broken metal piece. It doesn’t...

toolassociate.com

 

[rustedmetal]

How exactly are you fitting the heat pipes to the block?

If I were trying to affix heat pipes to a metal block and soldering is out of the question for some reason, then I would use thermal paste or liquid metal between the contact points and epoxy it all to seal it. And just hope it holds.

seems like a temporary job and it would be very unpractical to do this on some areas like attaching one end of a heat pipe to a fan enclosure case wich can have very uneven surfaces.

Just use industrial grade liquid/Epoxy metal

Best Metal Epoxy 2021 - The Ultimate Practical Guides for ALL Projects

What is the best metal epoxy? You might be a handyman or a mechanic or just another person with a broken metal piece. It doesn’t...

toolassociate.com

The problem with these epoxys is that they don't list anything related to conductivity and i have emailed them before inquiring on the matter but all they say is that they are not tested for that matter.

 

[CountMike]

seems like a temporary job and it would be very unpractical to do this on some areas like attaching one end of a heat pipe to a fan enclosure case wich can have very uneven surfaces.

The problem with these epoxys is that they don't list anything related to conductivity and i have emailed them before inquiring on the matter but all they say is that they are not tested for that matter.

Any paste or glue is made of substrate (usually silicone) and heat conductive metal or other material in very fine powder. That material and it+s density define it's heat conductivity. Epoxy/liquid metal is very dense with metal and shoild conduct very good.

 

[Ralston18]

Question regarding:

"since i was trying to avoid bursting the pipe "

I would not expect soldering to "burst" a pipe unless there was liquid trapped inside.

Wondering about the circumstances and what is actually being attempted?

Is it possible for you to take a couple of photographs and post here using imgur (www.imgur.com)?

 

[hotaru.hino]

seems like a temporary job and it would be very unpractical to do this on some areas like attaching one end of a heat pipe to a fan enclosure case wich can have very uneven surfaces.

Then explain the entire system so we know what we're working with.

 

[rustedmetal]

Any paste or glue is made of substrate (usually silicone) and heat conductive metal or other material in very fine powder. That material and it+s density define it's heat conductivity. Epoxy/liquid metal is very dense with metal and shoild conduct very good.

which is what i think as well but how conductive is it? Thats my question

 

[rustedmetal]

Question regarding:

"since i was trying to avoid bursting the pipe "

I would not expect soldering to "burst" a pipe unless there was liquid trapped inside.

Wondering about the circumstances and what is actually being attempted?

Is it possible for you to take a couple of photographs and post here using imgur (www.imgur.com)?

Well, heat pipes do have liquid inside and i saw a couple of them expand a bit while i was trying to solder them, as far as what is being attempted i'm looking to attach heat pipes to heat sinks to improve heat dissipation from motherboard components.

 

[rustedmetal]

Then explain the entire system so we know what we're working with.

All i'm looking for is to attach heat pipes to heatsinks with a more conductive Epoxy/glue than cheap chinese ones that only offer 1 W/ mk.

 

[Ralston18]

@rustedmetal

This : "1 W/ mk. "

You are not dealing with thermal paste where "1 W/ mk " directly applies.

My sense is that there are two different issues here:

1) Sealing/attaching the pipes.

2) Improving conductivity.

Seals/solder/glue/epoxy. etc. are to prevent leaks at joints.

The pipes are for the fluid carrying away heat.

Overall, as I understand the matter, the seals/solder/substrate do not need to be conductive. They need to prevent leakage so the fluid can carry away the heat.

However if the substrate (as I understand @CountMike 's post) helps with conductivity as well and sealing against leaks - then that would be a bonus.

Per @hotaru.hino

"Then explain the entire system so we know what we're working with. "

Again - I suggest including some photographs.

 

[CountMike]

Well, heat pipes do have liquid inside and i saw a couple of them expand a bit while i was trying to solder them, as far as what is being attempted i'm looking to attach heat pipes to heat sinks to improve heat dissipation from motherboard components.

Heat pipes are also coated inside with sintered metal that is like a sponge, heating pipes may detach and crumble that material making pipes useless. You are wasting time looking for anything else better than industrial grade liquid metal, it's 99% metal which is even more than metallic cooling paste ! It's also strong and could be even drilled tapped and hold bolts/screws.

 

[rustedmetal]

@rustedmetal

This : "1 W/ mk. "

You are not dealing with thermal paste where "1 W/ mk " directly applies.

My sense is that there are two different issues here:

1) Sealing/attaching the pipes.

2) Improving conductivity.

Seals/solder/glue/epoxy. etc. are to prevent leaks at joints.

The pipes are for the fluid carrying away heat.

Overall, as I understand the matter, the seals/solder/substrate do not need to be conductive. They need to prevent leakage so the fluid can carry away the heat.

However if the substrate (as I understand @CountMike 's post) helps with conductivity as well and sealing against leaks - then that would be a bonus.

Per @hotaru.hino

"Then explain the entire system so we know what we're working with. "

Again - I suggest including some photographs.

I'm looking to add an aditional heat pipe in this case to a heat sink to better the thermal efficiency of the CPU in this case. There are thermal glues and it doesn't have to be an epoxy as long as it's got good thermal conductivity.

@rustedmetal

This : "1 W/ mk. "

You are not dealing with thermal paste where "1 W/ mk " directly applies.

My sense is that there are two different issues here:

1) Sealing/attaching the pipes.

2) Improving conductivity.

Seals/solder/glue/epoxy. etc. are to prevent leaks at joints.

The pipes are for the fluid carrying away heat.

Overall, as I understand the matter, the seals/solder/substrate do not need to be conductive. They need to prevent leakage so the fluid can carry away the heat.

However if the substrate (as I understand @CountMike 's post) helps with conductivity as well and sealing against leaks - then that would be a bonus.

Per @hotaru.hino

"Then explain the entire system so we know what we're working with. "

Again - I suggest including some photographs.

Well, if the surface contact between the heat pipe and the plate making contact with the CPU is not anywhere near a mirror surface finish then how is the conductive glue/epoxy not needed? Low melting solder is what is used to attach them and to conduct the heat from the CPU plate to the pipe in the factory.

 

[rustedmetal]

Heat pipes are also coated inside with sintered metal that is like a sponge, heating pipes may detach and crumble that material making pipes useless. You are wasting time looking for anything else better than industrial grade liquid metal, it's 99% metal which is even more than metallic cooling paste ! It's also strong and could be even drilled tapped and hold bolts/screws.

View: https://youtu.be/9gKYfgIGMlE
FAQ | J-B Weld (jbweld.com)

 

[Ralston18]

The YouTube "conductivity test" video is not at all a valid test, comparison, or a conclusive result. No matter what the intended purpose.

Adding a couple of photographs to show your situation and requirements likely to solicit other ideas and suggestions.

However I will simply stay with not worrying about the conductivity of what ever is used to make the connections and seal the joints. Not having a leak is more important.