I got my XM-L2 U2 on copper and now want the best TIM available. I have a couple high quality pastes but unless I use screws to secure the star, a removable adhesive seems best. What’s everyone else using successfully for running very high currents?
At first, the Panasonic PGS (Pyrolytic Graphite Sheet) sounds impressive considering that it performs better than the copper. However, what isn’t clearly advertized is the low thermal conductivity where it counts. The sheets have superior thermal conductivity (>600 W/m*K) along its length and width only. Conductivity thru it’s thickness is just 15 W/m*K but will most likely have less surface contact than pastes and epoxies.
Polish a bit and then arctic aluminium 2k adhesive, I usually put it in a bench wise with a rattlenut over the led to press it together until it is dry…
I’m using Antec 7, mainly because that’s the best of what was available at my local Fry’s.
Goes on as a paste but, cures once on. Good enough for holding stars in place without screws. No idea how it compares to other stuff on the market, but it seems to do the job.
If you want a really secure star placement without screws and still have it removable, you can do what I used to do:
Put a dot of arctic silver epoxy right in the center of the star, below the emitter. Then around the dot and to the edge of the star, use thermal grease or thermal compound. You don’t need to epoxy the entire bottom of the star.
The dot of epoxy is more than sufficient to hold the star in place in any situation. If you want to remove the star, disconnect the wires and use needle nosed pliers to rotate the star. The rotation will break the epoxy and the dot and the star will come right out.
Some extensive testing at review sites have shown that the top ten TIM’s all perform very well (except for liquid metal based TIM’s, they’re legendary), well within 3-5 degrees of each other, and that’s not going to be noticeable in any way with LED applications.
I’d say go for the most accessible TIM that’s in the top 10-15th place.