1 Gram White Thermal Compound ???

**DarthHideous** · 05-21-2009, 11:32 PM

I just saw this as a new item. I couldn't find a thread on it.
Anyway, what is 1 gram white thermal compound ?
http://www.thecustomsabershop.com/1-...ound-P443.aspx
Does it have something to do with the heatsink ?

**Zook** · 05-22-2009, 01:47 AM

Originally Posted by DarthHideous

I just saw this as a new item. I couldn't find a thread on it.
Anyway, what is 1 gram white thermal compound ?
http://www.thecustomsabershop.com/1-...ound-P443.aspx
Does it have something to do with the heatsink ?

yes.

Most heatsinks and the product you attach it to have small imperfections and do not make 100% contact with each other. To fix that and fill in any small imperfections and also to help in the thermal transfer they make thermal compound.

**DarthHideous** · 05-22-2009, 01:55 AM

I thought the heatsinks at TCSS fit really well. At least in my builds. Which application would this apply to ?

**Dann** · 05-22-2009, 02:25 AM

These are most likely such small areas you wouldn't notice with the naked eye. This is the same sort of stuff they use with heatsinks on CPUs to keep them cool.

**strengthofrage** · 05-22-2009, 03:57 AM

Its a good idea to use it between each LED & heatsink. Even if the two look to be in complete contact with each other, this will still help.

**Zook** · 05-22-2009, 07:43 AM

Originally Posted by DarthHideous

I thought the heatsinks at TCSS fit really well. At least in my builds. Which application would this apply to ?

like the others just above me here said. The imperfection are quite small that it couldn't be seen with the naked eye. Basically this compound is a better conductor of heat than the tiny air pockets. you are dealing with mass produced parts and they are going to have imperfections.

Heck even on the high end CPU heatsinks you see people lapping them all the time to get them really flat and of course still using a compound (arctic silver etc).

**Jagahati** · 05-22-2009, 08:21 AM

Originally Posted by Zook

like the others just above me here said. The imperfection are quite small that it couldn't be seen with the naked eye. Basically this compound is a better conductor of heat than the tiny air pockets. you are dealing with mass produced parts and they are going to have imperfections.

Heck even on the high end CPU heatsinks you see people lapping them all the time to get them really flat and of course still using a compound (arctic silver etc).

I use Arctic Sliver on my LED mounts. I have plenty sitting around and it moves heat wonderfully. I am willing to bet that it is overkill for this application and its not exactly cheap stuff.

The white thermal grease Tim is selling should be plenty for LED to heat-sink bond and will probably increase the running life of an over-driven LED by a good amount of time.

I would use some variety of thermal grease when attaching LED's to heat-sinks its cheap and it works.

**ARKM** · 05-22-2009, 11:48 AM

Originally Posted by Jagahati

I use Arctic Sliver on my LED mounts. I have plenty sitting around and it moves heat wonderfully. I am willing to bet that it is overkill for this application and its not exactly cheap stuff.

While Arctic Silver is great for CPUs, it is not the best for some Luxeon LEDs. This is because Arctic Silver is slightly capacitive and the Red and Red/Orange Luxeon LEDs are known to sometimes conduct through the metal sheet on the bottom of the PCB. Here's a quote from the official website for the product...

"Arctic Silver 5 was formulated to conduct heat, not electricity.
(While much safer than electrically conductive silver and copper greases, Arctic Silver 5 should be kept away from electrical traces, pins, and leads. While it is not electrically conductive, the compound is very slightly capacitive and could potentially cause problems if it bridges two close-proximity electrical paths.)"

I believe there is a thread on this very subject somewhere in the TCSS forum. I think it was Novastar that explained all of this in that thread.

That said, I use Arctic Alumina instead of Arctic Silver for my Luxeon LEDs, to avoid the possibility of the above mentioned issue.

**Jagahati** · 05-22-2009, 11:47 PM

I was not aware of an issue with the Lux III's until you said something about it.

My first saber (And so far the only completed) uses a K2, as such I had not read up much on the Lux III's.

I did know that Arctic Silver was conductive and that in tight areas can have a capacitance that could in theory cause problems. I only say in theory because I have never experienced any myself.

For these applications I don't think it matters a whole lot what type of thermal grease is used (except where conductivity or capacitance may cause problems). The temperatures at the rated wattage or even "Over-Driven" wattage should be manageable for short run times easily enough.

We aren't talking about taking a $500.00 CPU and seeing how far we can push it. Just a fancy $8.00 LED and some minor tweaking.

All in all though thermal grease is probably a very good idea for LED's. It certainly can't hurt and it may mean you get a lot more lifetime out of some of the "hotter" set-up people try.