Okay, getting into the world of flashlight maintenance and possibly even modding. In regards to applying thermal paste, is this video a good example? (It’s what I’m finding on YT as far as thermal paste).
Also looking at putting something on the threads. I see silicone grease recommend. I watched OL’s five-part modding YT videos yesterday and he was using vasaline. Thoughts and comments welcome. Please take into account this is a new area for me and it’s only been recently that I came to understand terms like star, pill, driver etc.
Many thanks 
That video is a joke right? He’s putting thermal paste OVER the MPCB?
For lubricating the threads I use Nyogel 760, been testing silicone for a while but was not very happy with its performance.
That’s why I’m asking. I’d like to see a good video of what you guys do, and how so that I’m doing it correctly.
When it comes to shooting and fighting I’m a five star general, when it comes to this type of thing I’m a no-rank-Fuzz-butt private 
Look here
Think of the MPCB with the led as the CPU and at the body of the flashlight as the cooler/heatsink.
lol, it sure looks like a joke, or “how not to do video” he only needed to add a paste to the bottom of the star, which he never even removed from the pill. what he did in no way improved a heat transfer.
lol, just do not do what the guy in video did. that is not how you improve thermal path.
The beauty of the internet is you can easily share information freely with millions of people. The problem with the internet is you can easily share bad information freely with millions of people. Like that guy did.
Love the rusty common pliers.
Take a cotton swab or a small, clean piece of cloth and put some thermal grease on it. Apply it evenly on the entire base (read: underside), then press the emitter firmly onto the heat sink. If you’re using a particularly viscous grease or glue, try moving the emitter from side to side or in small circular motions (while applying more pressure)*, until the film between emitter and HS is as thin as possible.
Thermal grease doesn’t conduct heat all that well, about 15W/mK, that’s <1/10th of aluminum’s ~200W/mK. It’s there to fill the tiny gaps that exist due to the emitter/HS surface not being 100% plane, mirror polished perfect surfaces. Where metal can contact metal it should be allowed to do so, grease is for gaps and gaps only.
Ideally you’d screw down the emitter, that way pressure is applied most evenly.
’* don’t try that with a CPU
I just thought I’d quote this to re-iterate it’s importance.
Something like this; and then MCPCB on top, make sure to not put too much like bikedude has said. (mouseover)
Even that amount looks like it might be too much.
I have a small set of miscellaneous shaped exacto knives. One the blades is rectangular shaped with the cutting edge on the far edge of the blade. I use it as a trowel to spread the thermal paste in as thin and uniform a layer as possible.
well by putting the paste that way he is effectively increasing the surface area used to transfer heat from the mcpcb/shelf to the pill walls. The shelf is quite thin. All the heat transfer between the shelf and the pill walls is occurring through the surface of the edge of the shelf which is :
shelf thicknes * shelf diameter * Pi.
by adding the thermal compound on the shelf, he is effectively increasing shelf thickness, which could improve the conductivity to the pill walls significantly.
Yeah I used one of the plastic spatulas my CPU thermal paste came with afterwards to spread it around.
I usually use too much - but when you press and twist the MCPCB enough, you end up with a extremely thin layer of thermal paste.
So, that’s the way for me. Better a little bit too much than too less.
I usually use also thermal paste between pill and case.
To the guy in the Video:
This is the right way of adding thermal paste. Directly onto the LED, so the heat can leave as fast as possible.
Nah man gotta have the paste inside the dome for ultrafire level heat transfer ;)
I normally use a small syringe to carefully coat the die while leaving the dome in place. A nice thin layer right on top of the phosphor is ideal.
…
Of course I’m just here to echo what others have said: A nice thin layer of paste between your star (MCPCB) and shelf is correct. I posted about this in the F13 thread.
It’s a little nit picky but I’d never use cotton ball, cotton swab, ect to spread heat sink material. Cotton will almost almost always leave some sort of lint behind. If you are cleaning the surface you want something lint free, coffee filters are a pretty good and cheap option. Normally a rice grain size of grease is plenty. Larger MCPCB would need extra, but thermal paste is one those things that more equals less cooling
That is video is wrong in so many levels. I really don't see how applying the thermal paste on top of the MCPCB would help at all. Is the paste supposed to help moving heat from the MCPCB to...air? Huh?
When I use thermal paste, I treat the surfaces as if I was installing a heatsink on a CPU:
1. Clean both surfaces with isopropyl alcohol using a rag, then leave it to dry for a minute
2. From the CPU/overclocking days, I'm in the camp of using only a "rice sized" portion of thermal paste either on the underside of the MCPCB or the metal surface you are putting the MCPCB on. Said paste is put in the middle of the surface/MCPCB
3. I then let pressure spread the thermal paste around. I don't do any spreading myself. The pressure can be applied mainly in three ways. The first, which is preferred, you screw the MCPCB down. Next method is to leave as is and let the reflector/head/lens combo to put the pressure on the MCPCB. The last method is to use small drops of super glue on the MCPCB's edge and apply pressure until it sticks
You guys gave the thumb down in that video actually, right? :bigsmile: