C8 addicts thread

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Fritz t. Cat
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The Wikipedia article on 6061 aluminium alloy says “The typical value for thermal conductivity for 6061-T6 at 80°C is around 152 W/m K.”, whatever those units are. For pure Al, it lists numbers around 220 in what appear to be the same units, in the article List of thermal conductivities. Pure copper is around 390 and brass 120 in the same table.
So brass is nearly as conductive as hard Al alloy and suitable for pills when it is easier to fabricate, while alloys with higher Cu content have superior heat conductivity.
Heat conductivity of metals is loosely related to electrical conductivity, so alloys used for ground busses and such in electrical devices are good.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

Sirius9
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Haterade wrote:
Don’t have a scale to weigh them, but the C12 doesn’t feel much heavier in hand.

If I manage to find C12 somewhere with nice discount I’ll get one for experimenting :- ) It just looks like it has a better heat management than C8

P.S. (talking to everyone): have you seen this:

 

gords1001
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I would have to say your being pretty dammed anal to worry about the thermal conductivity of a brass pill over alu alloy tbh.

I have two similar sized, similar mass lights driven roughly the same, one, the emitter is screwed to the head – direct bonding, one has a brass pill, I defy you to feel a difference in how they heat up.

I certainly am not convinced you could measure a difference between a brass pilled c8 and an alu alloy pilled c8, interesting experiment though it would be.

me? I’ll take ease of assembly thanks

Tom E
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I even got a true copper pill (from VOB) in a LightMalls UF C8 and really can't tell the difference in heat and output between this light and others I have with brass and aluminum pills. Originally it had aluminum w/copper discs, upgraded to brass w/copper discs, and now just the copper pill - can't tell a difference.

The stock light would drop output as it warmed up like crazy - direct drive gone a-muck.

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The difference would be seen in how fast the outside of the light heats up. It may not affect the overall ‘hotness’ of the light since that is determined by the external features of the light and ambient temperature and not the pill. Honestly, I don’t know how much of a difference there is but personally, I prefer an Aluminium pill vs Brass.

My gratitude to those who are willing and able to help others (in whatever way you can)! Being human is more than just existing for yourself. Smile

crnkin
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Ive got 8 of VOB’s copper pills sitting here.

I’m not going to use them until ive found the best setup, 4 will be for my personal use, 2 each for my hunting buddies.

The biggest improvement you can make is going from alloy star with silk screen to a sinkpad. Straight away its got to be 30% plus much more stable, and longer life.

Artic silver has been amazing too, the lights get so much hotter, so much quicker than even Artic alumina.

Someone mentioned why the meter said 1801 lux and I have rated it at more. I don’t have time to play google but basically light intensity reduces at the inverse square per distance. So I measure at 8m, and multiply the reading by 64 (8×8).

Any more would be to spoon feed Smile

Chris

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Good stuff Chris.

Have a bunch of C8s (and a C12), XP-G2s, Intl-outdoor copper boards (16mm) and the Sinkpads sitting around… still waiting on drivers, glue and XM-L2 U2s (and maybe a XM-L2 U3). Will flick my measurements up once they are all together.

XP-G2s on copper at 3 amps are awesome!!! (and cheap).

I think the ultimate would be a XinTD V4*** with de-domed XM-L2 U3 on copper with one of PilotPTKs upcoming drivers… modded for up to 4 amps of cause. Wink

  • Can anyone confirm the XinTD has a deeper reflector then a standard C8?
Haterade
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You could email Hank from IO and ask him. He used to have a photo on his site of the V3 vs typical C8 reflector.

I like copper

Sirius9
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Manual Man wrote:
I think the ultimate would be a XinTD V4*** with de-domed XM-L2 U3 on copper with one of PilotPTKs upcoming drivers… modded for up to 4 amps of cause. Wink

Not quite sure in that! It would be a US$60 – $70 C8!

 

Fritz t. Cat
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Looking in Wikipedia reminded me that heat conductivity is limited by lattice defects (such as atoms of other metals). Some metals are supplied in a heat treated or work hardened form. This extra hardness is caused by lattice defects (They interfere with slipping along crystal planes). So heating the pill after it has been shaped and letting it cool slowly my make a significant improvement in its heat conductivity.
This is the opposite of the way knives are made, at least sometimes. The annealed metal is worked, such as by filing and grinding with abrasive belts and then it is hardened, tempered and polished. I am pretty sure budget light manufacturers wouldn’t bother with this step.
The conduction mechanism is that more energetic conduction electrons move to cooler parts of the metal and vice versa. The rate depends on the mean free path, as for atoms in a gas.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

gords1001
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if your driving your emitters hard enough, pills should soon get heat treated….. :bigsmile:

crnkin
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Fritz t. Cat wrote:
Looking in Wikipedia reminded me that heat conductivity is limited by lattice defects (such as atoms of other metals). Some metals are supplied in a heat treated or work hardened form. This extra hardness is caused by lattice defects (They interfere with slipping along crystal planes). So heating the pill after it has been shaped and letting it cool slowly my make a significant improvement in its heat conductivity. This is the opposite of the way knives are made, at least sometimes. The annealed metal is worked, such as by filing and grinding with abrasive belts and then it is hardened, tempered and polished. I am pretty sure budget light manufacturers wouldn’t bother with this step. The conduction mechanism is that more energetic conduction electrons move to cooler parts of the metal and vice versa. The rate depends on the mean free path, as for atoms in a gas.

Might make a small difference, but Copper and Brass don’t need to be cooled slowly like a lot of other metals. You can anneal it by dropping it in a bucket of water, or cooling it 1 degree an hour, it will still end up metallurgically the same.

Id say the brass gets pretty hot in flashlights, would have to be over 100 deg C in a hard driven light I would think. Not quite enough to anneal it though Smile

Ben, sounds awesome.

Graeme came around last night and picked up some xml2 c8’s, the ones in the first post.

Took him outside with the 125k xpg, and a stock xml u2.

It didn’t look 6 times brighter, but I guess thats colour temps playing with you! Im thinking about dropping even on more colour bin for the next lot, the 6500 de domed is perfectly neutral to me, but I think going one more down will be better with tracking blood etc.

Working on a DD at the moment, its all hinging on if the factory switch can hold 4.something amps going through it.

Hoping for 100k XML2!

Chris

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tivo532 wrote:
Re: Post#13
crnkin,

“_So thats 115,260 lux at 1m at 2.85a (7x.35s and 1 .38) was 99,000 lux at 1m at 2.50a (7x .35’s)._”

I see 1807 from the lux meter, please advise how you got 115,260 Lux.
Also on your first post, you have 68,200 Lux at 8M, is it 68,200 data from the Lux meter at 8 meters? Beer

I didn’t get any reply from crnkin, can anybody help me understand his readings.
The highest I can get from my C8 is 25,000 Lux from my Lux meter at 1m.
How he got 115,260 lux at 1m where he shows 1807 from the meter. Beer

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measured at 8 meters?  that would be 115648 cd

crnkin
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crnkin wrote:
Ive got 8 of VOB’s copper pills sitting here.

I’m not going to use them until ive found the best setup, 4 will be for my personal use, 2 each for my hunting buddies.

The biggest improvement you can make is going from alloy star with silk screen to a sinkpad. Straight away its got to be 30% plus much more stable, and longer life.

Artic silver has been amazing too, the lights get so much hotter, so much quicker than even Artic alumina.

Someone mentioned why the meter said 1801 lux and I have rated it at more. I don’t have time to play google but basically light intensity reduces at the inverse square per distance. So I measure at 8m, and multiply the reading by 64 (8×8).

Any more would be to spoon feed Smile

Chris

Answered it a few days ago

Chris

tivo532
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Thanks Chris. Somehow I missed your reply or else I’ll not post again about this.
Not that familiar at all with this Lux data and still learning. Beer

crnkin
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No worries buddy!

Chris

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wich AR lens for C8 besides de UCL?

kaidomain? fasttech ? IO ?

anyone has review of the other 3 ?

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I have a Convoy C8 with a Qlite, a Xpg2 on a noctigon and an AR lens. Today I got a duel stage Xpg reflector to try out. Unfortunately when I put the reflector in the emitter was pulled off. I think the hole for the xpg is so tight that it caused the problem. I would like to replace the XPG and try the reflector again but don’t want to have the same problem. Any sugestions?

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I just built an XPG2 C8 with OP reflector from KD and a 5xAMC driver from FT. Well after tweaking the pill height vs reflector it gave out a bright and well focused beam. Smooth too. I don’t have a lux meter but after a try outside, C8 vs Armytek Predator 2.5, I can’t say C8 is much behind of Predator. So it appears the $60 difference is all for the build quality I paid for Predator. I feel somewhat guilty. Smile

I can justify $40 quality light vs a C8, due to better builds, water resistance, body strength, modes, efficiency etc. But if you want a small size thrower, a C8 can still beat the lights a few times more in price.

Kokopelli
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I just built an XPG2 C8 with OP reflector from KD and a 5xAMC driver from FT. Well after tweaking the pill height vs reflector it gave out a bright and well focused beam. Smooth too. I don’t have a lux meter but after a try outside, C8 vs Armytek Predator 2.5, I can’t say C8 is much behind of Predator. So it appears the $60 difference is all for the build quality I paid for Predator. I feel somewhat guilty. Smile

I can justify $40 quality light vs a C8, due to better builds, water resistance, body strength, modes, efficiency etc. But if you want a small size thrower, a C8 can still beat the lights a few times more in price.

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I was wondering have any of you guys found a replacement tail switch for the c8 that can handle higher amps? I have ruined two of them with a build I am doing with a red phlatlight direct driven from ncr18650pd battery.

tivo532
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mhemling33 wrote:
I was wondering have any of you guys found a replacement tail switch for the c8 that can handle higher amps? I have ruined two of them with a build I am doing with a red phlatlight direct driven from ncr18650pd battery.

!http://i1309.photobucket.com/albums/s636/mhemling33/Phlatlight%20C8%20Bu...!

mhemling, see this thread. Beer

mhemling33
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Thanks for the link!

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Haterade wrote:
Fritz t. Cat wrote:
Has everyone here seen the test of a new XinTD C8 SC-82/V4 here http://budgetlightforum.com/node/21824 ? Do you agree with his opinion of it?
Don't have a V4 - yet. My V3 is great. My LM C12 is brighter, but the XinTD gets used more because of better modes (no strobe), and better tint (3c). And it just feels nicer in hand. Yes, it cost more, but still seems worth it, IMO. The new 5B tint option sounds fantastic to me.
LMC12XML2 today. And partly because of your short review and posts. Thanks Tim 

Lj

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got my first c8 the other day, the banggood 8.88 xml t6, and i like it.
its bright, throws well and has usable spill, the only downer is a hollow pill?? star only sits on a small edge so i wouldn’t run it on high for a long time. oh and the next mode memory, i hate it its s frustrating its my first light with it |(

i also have the convoy c8 on the way. im very interested to compare the 2

IN Caver
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I have both the C8 from Banggood and the Convoy. You will be much happier with the Convoy. The quality is much better.

dead led
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IN Caver wrote:
I have both the C8 from Banggood and the Convoy. You will be much happier with the Convoy. The quality is much better.

for 8 bucks i like it :bigsmile:

i just posted in the bangood 7.99 c8 thread, im interested to see weather yours has a hollow pill and what amps yours pulls on high?

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I agree it’s not bad for 8 bucks. The pill is hollow and I pulled the switch out and it looks kinda cheap to me. I tried getting measurements on high and the best I got was .87A but my DMM is a turd from HF so I have no idea if thats acurate.

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The XM-L2 U2s finally arrived so I stuck one in direct drive in a C8:

Stock C8 (Ultrafire, XML on Alu board) was ~22K lux (700-750 lumen)

With XM-L2 U2 on copper:

Before de-dome was ~42K lux (1300-1400 lumen?) After de-dome is ~85K lux After de-dome without the front lens is ~95K lux

Current reading was ~3.5 amps but probably closer to 4 without the DMM… I will try compare lux readings with and without the MM.

Over 10% is lost due to the front lens alone, time to get some AR coated lenses (99% transmittance) for them I think as well as better switches (shorted the battery and got a puff of smoke from the one I was using)

Will stick up results for the C8 XP-G2 once I get around to piecing it together.

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