C8 addicts thread

I’m just going to direct drive it to keep it simple. I’ve tried an MTG2 P60 DD before off 2x 16340 IMR so it should work. I’ll make another thread if the whole thing comes together.

I made some measurements and calculations to get the total mating area between pill and housing of my C8, C12 and XinTD V3. Surprisingly, the C12 with it’s larger pill and more threads had the least! The narrower flange and sloppier threads are to blame. Keep in mind, the area actually making contact is going to be less because of the typical surface imperfections. The 2mm wide flange contact only left a 1mm wide mark on the C8 so, in reality, the C12 is better but with a TIM, the C8 wins. For comparision, I added a the approximate area of a 20mm star. The C8 and C12 are from DanceLite.

C8 _ 220 mm²

C12 186 mm²

XinTD V3 262 mm²

20mm star _ 250 mm²

Looking forward to seeing your results! :slight_smile:

Hi Tom.
Previously I was only getting 29kcd until I tried a different battery from a laptop pull. This is a CGR18650DA and getting around 40kcd on a XM-L2, 12x7135 and Nitro sink pad.
What value were you getting before de-doming the LED?
Both springs with wires (instead of braided wire). What other mods I can do in addition to de-doming to get close to 100kcd?
:beer:

Before de-doming, about 45 kcd, one as high as 50 kcd. I always use a UCL or high qual AR lens. So, you have a 4.2A Nanjg (assuming 350's) - are you measuring 4.2A at the tail? If not, you need a better, lower resistance cell. best is Samsung 20R, but a 20Q or Pana PD, or SONY 30A may achieve it or come close. When you are over 3 amps with a Nanjg driver for an XM-L2/copper, you need a low resistance cell.

Hello folks, this thread is very informative, thank you all.

I have my parts list put together for my first (this in-depth) build and my first C8, I have a few questions. I am going to buy a convoy C8, from what I’ve gathered from this thread its about the best starting point without going up >200% in price. This is going to be a dedicated thrower that will be used sparingly an rarely turned on for very long at a time. My biggest concern is a good single mode driver I can stack 7135’s on.

I had planned to use this nanjg 105c but I’m concerned that I won’t be able to stack 7135’s on it since its non-PWM. Is that wrong? I see it uses 7135’s but I read over at CPF that stacking chips only effects the PWM levels. If that’s correct can someone recommend a single mode driver that’s either ~3.4A (what I want it to run at) or less that I can stack on. If there is a good 3.4A single mode driver I’d rather just do that to save on the tiny component soldering.

This is my parts list, does it look like everything I need?
From FT (Sku)
Convo C8 SMO ( 1272100)
Bare 7135 chips (1197600) ( if the exact driver I want can’t be bought)

From IO
Warm white XM-L2 on 16mm Noctigon
nanjg 105c single mode
42mm UCL glass
20mm PCB mounted forward clicky

Other crap
22AWG leads
AS
copper braid (for springs)
Copper slug to fill pill
Black switch boot- What size does the C8 use?

You can stack 7135's on that driver, no problem. 7135's act as current limiters. For example, if you add 3 350 7135's to bring the total to 3.85A, then 3.85A is the max limit but does not guarantee you will be at 3.85A, you could get less because of voltage drops from resistance, resulting in less amperage. No idea what they could have meant about stacking chips only effect PWM's -- maybe one particular, weird driver? PWM's I suppose you could say are effected because all modes are effected: Hi, Med, lo, etc... Hi usually has no PWM's - PWM's are there as a cheap (digital) way to implement medium, low, moonlight modes.

For that fwd clicky, not sure how you would go about mounting/fitting that - dunno, maybe you researched that already. By UCL, you mean AR lens I assume - only place I know of to buy a "UCL" lens is from flashlightlens.com for a bit more $$$.

By AS, we usually use AS5 (Arctice Silver 5), generally thought to be the best for the cost. Also, I always use Nyogel (here) on the threads with o-rings - I swear sometimes it even boosts output, but not sure, but never seen it hinder output either. You may be able to find it somewhere cheaper, dunno.

For that choice of LED's, I assume you are aware you will get significantly less lumens, but get a nice warm white tint (T3 vs U2 bins, 4 bins separation).

The list is impressive!

Oh Note: Those 1 mode drivers are funny - no micro, no low battery warning or auto shutdown, just 7135's on a board basically. For $4.15 cost, while from FastTech, I've bought dozens of these: amc7135-2-group-25-modes for $2.68 at qty 5, and then program them myself with any modes I want.

One More Note: You could buy the Convoy C8 as a host, but you'd have to buy an SMO reflector separately, still little cheaper though.

Hey thank you sir, I didnt know the SMO reflector was avaliable, I originally looked at the host only but wanted SMO, I’ll search for it now and go that route. I would prefer to use one of those drivers you linked but I didnt think you could make them single mode only, can you? As far as the switch, I hope its right, I found it from a thread linked earlier in this thread, even if it won’t work on the PCB I should still be able to use the forward clicky and I actually needed one of those 20mm PCB’s a few weeks ago so it’ll be a welcome addition to the spare parts bin, those boards are relitively hard to come by when you need one.

As for the lower lumens with the warm white T3, I always prefer the <4000k tints, I have T3 XM-L’s I’ve swapped into a few lights and I love warm (or at the very least neutral) tints more than I care about the slight increase from a cool white emitter.

On a releated note where can I find XP-E2’s?

I can make them single mode by re-progamming the Atmel TINY13A, but actually, I never built a single mode version because with mode memory, never felt the need, but maybe with a fwd clicky it would be more applicable.

Well according to this: http://flashlightwiki.com/Cree, difference between a T3 and U2 is 300 lumens at 3 amps, bigger difference at higher amps. I'd consider ~350 lumens a pretty big chunk and will make a pretty big difference in throw, but that's the trade-off. It's a shame with the technology now we have to pay a performance hit for nice tints.

we must be patient, if what cree is showing off in their latest and greatest makes it to consumer level we will be very happy in the future

Forward clicky in a C8 tailcap:

White ring on switch boot is a soft plastic spacer, otherwise tailstanding is a little wobbly. I think the black spacer came from a different light but it's a pretty common part, it came from the leftover parts box. Add flat washer/s for shimming if needed. This one still has the raised nubbin thing inside the switch boot, if that were shortened or trimmed off completely it wouldn't need the flat washer, but the tailcap stack height is short enough that the tailcap seats fully against the battery tube so I don't do stuff like that to gain extra space if it's not needed.

On some of the smaller lights space is so limited with the tall forward clicky switch that the threaded retainer has to be omitted, with the switch PCB sandwiched directly against the rear face of the battery tube.

Thanks for that pic and instructions. I don’t care if it doesn’t tail stand, actually i like it if the tail switch sticks out so thats good to see you have to work with it to make it not stick out. I have one of those black pieces around here but is it necessary if I want it to stick out farther?

Use anything as a spacer that gives enough room between the inside of the boot and the switch plunger, if it's not thick enough the boot will keep the plunger partially depressed. Spacer needs to sit on the square base of the switch and compress the flange on the boot for a good seal, hell I guess you could use a piece of wood if you wanted to go to that much trouble and didn't have a big box of spare parts laying around.

I just replaced my reflector with the OP from Fasttech. The outer rings are gone and hotspot blends nicely into the spill with no apparent loss in intensity. I went to order more but now they’re discontinued. Anyone know of another source for these?

https://www.fasttech.com/products/1208500

Edit: Found them at Aliexpress but recently, after waiting a 7-day long processing period before being told an item was out of stock and automatically cancelled, I’d rather shop elsewhere.
http://www.aliexpress.com/item/42mm-Diameter-Orange-peel-CNC-Aluminum-Reflector-FOR-CREE-XM-L/899315832.html

i’m waiting for an OP reflector from fasttech :wink:

Do you thing that a C8 with a XP-G R5 could be a good choice?

Good choice for what? Throw? -> yes (especially dedomed). For overall lumens output? -> no…

yes i wanted to say about throw :wink: …it has a good beam profile? the spill is large like an xml?
I own already a C8 XML (i want to place the OP reflector on it) and a C12 XM-L2….so now i’m considering an XP-G!

Well, it’s not expensive so I think you should try it :wink:

I received my double A/R lens from cnqualitygoods today. I got 3 for $1.90 but expected, at that price, it would only be one. They came wrapped in about 10ft x 6in of bubble wrap. The packaging and shipping alone was worth more than what I paid. It took 12 days from when I paid which I think was pretty good.

http://www.cnqualitygoods.com/goods.php?id=1970

To those who tested and posted the resulting gains of A/R coating, thanks! :slight_smile:

xp-gs are definitely different animals to xm-ls, at this point though, having both xp-gs and xp-g2’s, I would strongly urge you to get a noctigon mounted xp-g2 from intloutdoor, couple it to a qlite driver with the fourth star soldered and enjoy one of the best flashlight builds you can find, if its staying domed, get a 4c tint or close, dedomed go for a 1a or 1c ish tint.