What thermal paste/grease/compound should I be using?

I want to improve the thermal path on some p60 style drop ins and other custom drop ins I’m planning. What are some good products I should be using? Do any of these have bounding capabilities?

I did not use any, I am also looking for one.

Found these:

http://www.arcticsilver.com/

In some forums many people recommended this:

http://dx.com/p/fujik-silicone-thermal-glue-50ml-grease-like-4579?utm_rid=43033281&utm_sid=1&utm_source=affiliate&utm_medium=dealextreme

Anyone used?

Not an expert, but I only use normal thermal paste for cpu, dab a little onto the copper pill for led to sit & away it goes ~ :bigsmile:

Oh ya, dropin wrapped with alu. foil too ~ :wink:

Are there any Asia source for Arctic alumina thermal adhesive ?

I don’t trust fujik siliconne.

Artic Silver is an epoxy, is difficult to remove, and slightly capacitive. Artic Silver 5 is a grease like compound that is not adhesive. Artic Alumina is also an epoxy but not conductive or capacitive. Fujik is okay if you squeeze out ALL of the excess to the point that you have metal to metal contact but otherwise it’s not much better than caulk. I use it mostly for potting wires to protect solder attachments and temporary attachment for testing.

For a thermal adhesive, the best I’ve ever found is Wakefield Deltabond 155
http://www.wakefield.com/Catalog/tabid/92/CategoryID/110/ProductID/362/Default.aspx

For a thermal grease, the best I’ve ever found is Parker Chomerics T670
http://vendor.parker.com/Groups/Seal/Divisions/Chomerics/Chomerics%20Product%20Library.nsf/24eb4985905ece34852569580074557a/c72bd4ba4470f5ff852570ce006d53a0/\$FILE/Thermal%20Grease%20T650-T660.pdf

For a thermal phase-change material, the best I’ve ever found is Park Chomerics T557
http://vendor.parker.com/Groups/Seal/Divisions/Chomerics/Chomerics%20Product%20Library.nsf/24eb4985905ece34852569580074557a/9a63f6ee5b922f278525787600620419/\$FILE/Phase_Change_Excerpt.pdf

I’ve got a lot of hours into studying this stuff, and one thing I can tell you - Arctic Silver/Alumina/Whatever is garbage. Marketing hype. The two chomerics materials will blow arctic silver away…

PPtk

I just use some Fujik mixed with some Arctic MX4 i got from my local computer store for a few bucks.
I Mix it about 60/40. Fujik/MX4
Holds great, isn’t runny and dries pretty fast, and both are none conductive.

Thermal conductivity of Arctic Silver/Alumina is not great that's for sure. But it is relatively inexpensive and is easy to find in the US. I think that they are fine for flashlights. The key is to apply an extremely thin layer so that you get mostly metal to metal contact with the paste filling only the tiny gaps in between the mating surfaces. That's the idea anyway. Well, it's better than using nothing.

For use with P60 drop-ins you don't need bonding as the reflector should hold the emitter in place. Any kind of non-adhesive CPU heatsink paste would probably work okay. Use the non-adhesive stuff as those are easier to apply a thin layer of. The thing that matters more is the quality of the mating surfaces. The flatter and smoother the surfaces the better to maximize metal to metal contact.

Stay away from thermal tapes and thermal pads. You want metal to metal contact and those get in the way of that.

Almost forgot about this. This stuff is really cool. It’s in the same general ballpark as the Chomerics materials, but it’s easier to get and easier to use…

Parker Chomerics Thermal Tapes also do a pretty good job.

Yep, we’ve used T405 for securing the ‘Cold’ side of TEC Modules to a “Cold-Sink”. It’s not nearly as thermally conductive as the non adhesive stuff (T557/T777), but considering it’s 2 sided adhesive, it’s pretty darn good.

I use Arctic Ceramique2 for thermal paste, when I don't want a permanent bond and Arctic Alumina Thermal Adhesive for when I want a permanent bond. Seems to work fine. Adhesive, when I don't want to screw down a led star and paste when I do (or in a P60 drop-in).

Today I found a thermal compound accidentally at home for cpu mainboard etc.

And I used it for a Ultrafire 502b with xml u2.

Also used some aluminum foil.

I am astonished by the results. P60 drop-in area gets hot in nearly 5-10 seconds in high mode, the led produces a cooler white light and it is brighter than before! :slight_smile: :open_mouth:

f42,

You think it moves heat well now - try doing the wrap job nicely. All those air gaps SERIOUSLY take away from the thermal transfer ability of the foil. You want a TIGHT wrap.

Also, the thermal paste on the top of the star - completely useless… Good for making a mess, I suppose…

PPtk

Thanks for the warnings :slight_smile:
It is tight in the center, I wanted foil to touch body of flashlight.

making a mess like what?

A mess like that in the pictures. You should use the paste to help transfer the heat to something. In your case, at the top of the star there is only air. So you should clean that thermal paste out.

Lol, I thought something dangerous could happen. Then we transfer heat to the air :wink:

Agree 100% Fujik is pretty shitty compared to Arctica Alumina.

Saw this on CPF for dopins Improving heat sinking on P60 style drop ins. | Candle Power Flashlight Forum

Air makes for an excellent insulator. I would take the advice offered you.

I’ve used some of that Chomerics stuff (not sure what paste, it was a free sample) and it seems to do a good job, but I’m unable to do fine enough testing to tell the difference between that and cheap Chinese thermal paste. Then again, I do lap and polish all my thermal interfaces and screw them together, which probably has a bigger effect on transfer than whatever paste I’m using.