OTR i3 project [was: Need advice: Thermal paste between pill and body?]

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Unheard
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OTR i3 project [was: Need advice: Thermal paste between pill and body?]

Anyone tried to apply thermal paste to a pill?

I ask since this would be a one-way action for the OTR i3 due to the design of the pill (a reflector is screwed onto the pill, and the assembly can only be removed by grasping the reflector, which would unscrew from the main part, leaving it in the body).

Background: My i3 got a new driver, currently drawing 2.7A from a Nitecore NL166, but I plan to use a higher discharge, higher capacity Vapcell, so likely current will increase.

Theory pro thermal paste: There should be lots of air cushions between body and pill that could be filled.

Theory contra thermal paste: There’s enough surface left which makes good contact.

So, an experiment is needed, and maybe some of you already did this and know if heat dissipation can be improved.

Opinions are welcome, too.

Edited by: Unheard on 09/16/2020 - 08:37
Barkuti
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I've applied some thermal paste a few times just for the sake of it. Can't provide measurements. There should be some improvement, but I think it's going to be quite small, and I mean rather quite small. 

Some investigation would be of help, but needs some careful set-up, though.

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Henk4U2
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You’re right, the middle of the threads wil make good contact.
But because of tolerances there will be air gaps at the top and bottom of the threads.
I don’t know if you gain a lot, but I think it won’t hurt to apply some thermal paste.
Downside, if that hardens (cures) it will be more work to get the pill out again.
So use thermal paste that stays soft and mushy.

PS, I don’t use thermal paste but I clean the threads very thorough after removing the pill.
That way I hope radiation will compensate for part of the missing contact area.
When assembling the light I re-apply some lubricant on the (outside) threads of the tube.

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Unheard
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Ok, Gentleman, thanks!

I’ll do it. Will measure and report back, but takes sometime until I have a proper cell.

contactcr
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I tried it once and it was too messy. Would not do it again personally.

If you ever have to adjust or remove the pill paste will get places you don’t want, even places where ground contact might be made. Nightmare to clean and requires a ton to “fill gaps” in something like threads. Dont bother.

KawiBoy1428
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I tried it Once.. 6 years ago… Facepalm

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The 502b had a poor heat dissipation design. You might look there to find a few different ways people tried to improve it.
http://budgetlightforum.com/node/8062
From some of the test on here I have sen about adding thermal paste, it seems when to much is added it doesn’t help that much.
A thin layer was tested as the best, in this situation for fill it should help but I would guess to say not alot.

Unheard
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KawiBoy1428 wrote:
I tried it Once.. 6 years ago… Facepalm

Not good?
Unheard
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moderator007 wrote:
A thin layer was tested as the best, in this situation for fill it should help but I would guess to say not alot.

Ok Thumbs Up
Unheard
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contactcr wrote:
If you ever have to adjust or remove the pill […]

Won’t – can’t. Difficult enough w/o the paste. But I had already in mind that it likely will be a mess.
Unheard
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First impression of temperature regulation of Crescendo:

Will repeat with new cell.

Very rough lumen estimation: max. 900lm

Unheard
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I messed it up. Ordered a 1×2mm Osram since I wasn’t aware the 2mm^2 LEDs are not square Facepalm

Also, it is not centered. Had no fitting gasket, and it is really difficult to do it this way.

But: It sucks 3,9 amps out of that old NL166 now and makes 51560 cd / 454 m.

Of course, the beam is full of artifacts. Looks terrible.

contactcr
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The result looks fine to be honest, you can black out some stuff to clean up the artifacts and call it a day. On the much larger Z821 I was not able to break 7x kcd so your result looks good on paper. I tried a 1mm2 NM1 and the result was single digit throw increase, for sure not worth it and ultimately went back to 2mm2 LED.

Unheard
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contactcr wrote:
I tried a 1mm2 NM1 and the result was single digit throw increase, for sure not worth it and ultimately went back to 2mm2 LED.

I’ll keep the LED Thumbs Up
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Sorry if there’s an obvious answer: Any way to switch off temperature regulation except just adjusting temperature in Crescendo (where it gets as hot as possible)?

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