help me decide for friends' C8

ok I had my convoy c8 with an xml2 and chips stacked to 4.9A, tail spring bypass—at a cookout and a couple of guys were freaking out about wanting one—they just say “I want one just like yours” should I throw together the exact same thing or go with an xpl-hi at 3A… I figured there would be less heat, as good or better throw, and better runtime. it will use protected cells and I’ve already warned them numerous times about the caution needed with li-ions. what do y’all think. I’ve also been asked to put together an s2 which I’ll be running at 2.8A —- should I use an xml2 or xpl-hi for that—-I have already given some s2’s ith xml2 as gifts to several people . thanks in advance

C8 with XPL HI at 3A should throw pretty good, maybe even mind blowing throw for normal people. But for the S2+ you wouldn’t see much difference running XPL HI, so even in the stock form with 8 chips and XM-L2 should be bright enough with decent reach. To avoid overheating I would limit the driver to only 5 or 6 chips.

If the purpose is seering brightness, then a little heat is to be expected. Not especially useful, but my reading of the OP is that his friends want to be impressed.

Functionally, my conjecture is that they might be better off with a 7135*3 setup, putting out ~460 lumens and much longer battery life. But if brightness is what they want… }:slight_smile:

They totally do :smiley:
I will endorse my one all year long ! I can bounce light off a white wall ~320m away,prob further if I tried.
Effective range depending on the terrain is 200-250 metres. Bit further for general semi-detailed lighting.

8 chips, and heat really isn’t too bad, more ‘reasonably warm’.

When you designed your C8, you built the flashlight that you wanted. Now you say that your friends like the design.

You also seem to be saying that if you were designing from scratch today, you would use an XP-L HI in a C8 flashlight you built for yourself. If you were making the thing for yourself, would you push the amperage above 4 amps? If so, perhaps you should also do that for your friends.

Evidently, they want the light you would want. }:-)

Same as when speaking, when gifting I keep the receiver in mind and I allow room for misunderstandings. Since it takes lots of lumens to make a visible difference you should ‘throttle down’ a little so their lights have less potential for problems.

Everyone loves a winning hot-rod but if the motor always blows just past the finish line the fun fades away rather quickly whether you won or not.


what driver did you use to get 4.9A?

I added/stacked 6 more 7135 chips on a regular 3/5 mode driver

The brightness may not increase much - but when I changed the stock XM-L2 to XPL-HI in my S2+ I noticed a much clearer beam and more throw. The stock driver does change modes if you switch off the light after the short blink which appears in low mode after 5 seconds. This is annoying so I used the BLF A17DD, which has a turbo-stepdown. With protected batteries you probably won’t get much more than 4 Amps, so heat should not be a big problem.

XP-L HI and fet+1

Both my S2 and C8 with XPL HI run right at 3.8A. To me that’s just perfect. I have no heat issues and can leave them running for as long as I like, and there is a noticeable difference when running below ~3A.

Also, if you go S2 rather than S2+, purchase the SMO reflector (available on mtnelectronics). With an XPL HI it will throw as far as my stock C8 with XML2.

I’m probably going to go with the xpl-hi for the c8’s and regular xml2 for the s2 which I always recommend as a utility/house light so the flood is actually better (well IMO for working on something)