C8 upgrade

LED Flashlights – General Info 18650 Flashlights
1

Ok guys, tonight i was thinking, lets upgrade the stock wires from my convoy C8.
All went well, soldering went easy with clean and beautiful connections.
I put all parts together and tested the flashlight and discovered that i have only 2 modes, which are ON or OFF :frowning:
I measured current, but on a 3,7v cell i measured 2 Amps (sidenote, standard hirschmann 1m leads)
Could it be that some solder went to a place where it doesnt belong?
I am always careful about that, but since it is small stuff, you never know.

Since fallbacks create new opportunities :slight_smile: the next
question would be;
what would be a good driver to upgrade with?
Is it worth trying a complete new combo with led and driver?
Since the C8 is all about throw, what would you recommend?
Dedomed XPG2/3 XPL-Hi? Or even bigger LED’s?

Regards
Pieter

2

You mean like this?

S5/DD FET and a good BLF centering /tunning makes miracles with that host, we are doing that every day here :+1:

3

on and off means DD so you got shorted LED minus to body

4

Holy crap!
Is that Simon his Bulgarian factory ? :smiley:

That sounds interesting, do you have any more details on that?
.
@Lexel
Any ideas where the shirtcut might have occurred? Since everything seems very clean and perfectly fitted

5

Yep. See if your reflector is hitting one of your new solder blobs on the MCPBC.

6

Wow Mitko… it looks like you have “cornered the market” in Bulgaria. :+1: . :beer:
.
:slight_smile:

7

Possible spots for LED minus short to body
DTP star LED footprint shorted with tin

LED wires to reflector or damaged insulation

Driver Solder blob for wire hits body
Driver short when soldering LED minus wire to a pad with ground

Faulty 7135 chip causing a short

8

If the led + wire also bridges to one of the 7135 pwm pins it will lock into high mode(regulated not DD), if led- bridges to ground(either through the reflector or on the driver) then you get DD. 2A suggests it might be where the + wire is soldered on the driver.

9

Looks like my C8 army… :smiley:

10

To me, a C8 is a specialised thrower, so I replace the come-with driver with a generic 17mm 1-mode driver.

For XP-E2s, that’s 1.05A or 1.40A.

For XM-Ls, a 1.75A 1-mode or 2.1A/2.8A NANJG 105C.

No XP-Gs yet (on order), but was going to try a 1A dedomed or 3C stock, push ~2A through it.

11

Thanks for all the ideas guys!
Unfortunately i do not have time for it to check until tomorrow, but i will keep you posted.

12

I am not sure whether the 2A current draw can tell your light actually goes DD or regulated unless you are sure that the leads are truly heavy gauge ones.

But anyway, nice try on the modding! When I first started modding flashlight I too have ruined and damaged things, that’s normal and also part of the process.

Try to check all the contacts as what Lexel suggested above. Another tip is that you may want to use your DMM to perform connectivity test on all the contact points.

13

I had a quick look tonight, unscrewed the bezel and reflector and turned on the light.
Unfortunately i observed the same behaviour.
Probably the GND wire to the driver, i think the OUT from the 7135 has contact with the GND wire, will inspect it tomorrow (hopefully)
Otherwise the thicker wires which were quite stiff might cause a problem, we’ll see

If it doesnt work out i will have to buy another driver (how annoying :smiley: ) i was thinking to try the astrolux/BLF driver.
Can anyone tell the difference between the X6/X5 and the S1/BLF A6 driver?

14

One has BLF A6 firmware and the other has bistro firmware…both written by Toykeeper. As far as performance goes…they both give near direct drive capability. I prefer bistro myself.

15

So today i found some time to open it up again
I found out that the + wire made a solder connection to the diode, also the -/GND had a connection to the OUT pin of the nearest 7135.
When i removed all solder and tried to reconnect everything, the stiff upgraded wire broke a line of the pcb when fitting it into the C8…

So i found an unused convoy driver with 6 chips, unsoldered the 7135 from the damaged one (damaged some during unsoldering) and managed to add 3 to the original 6x 7135 driver (from which 1 stacked) and assembled everything again.
Tailcap reading only showed up 2,5A, compared with an S2+ with 8x7135 i measured 2,75A
So it seems that i damaged some of them during unsoldering and 2 out of three are not functioning, whilst soldering job looks quite good.

For now im done with it, maybe when i feel i need to upgrade it i will buy the X6/X5 driver, maybe another LED as well. Was hoping to get 3,1 A