Hello Everyone,
I’ve looked at (disassembled and modified) several ak-47 (Trustfire) flashlight and even switched out an OEM driver board with the KD ($20 ish) higher powered driver board for this 9xT6.
Here’s some data on the OEM (Original Equip Mfg) driver board in case you just need quick flashes (less than 60sec) of light at higher intensity than a stock ak-47 can do.
This is the stock/OEM driver board for ak-47 9xT6
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Notice the two resistors are 2 ohms and 0.82 ohm with a space open.
2 ohms // 0.82 ohm = 0.581 ohms
Any third resistor R10 slot added to the space was first assumed to be in parallel with this 0.581 ohm equivalence.
Here’s some data:
R10 Requiv 5Amp PS Trustfire MNKE
26650 26650
—— ———- ————— ————- ———-
J-18 mod 6.19 6.17
AK47 stock 2.53 2.52 2.79
Akmod - 0.581 2.45 2.67 2.73
10 0.549 2.69 3.00 3.08
5 0.521 2.84 - 3.25
3.3 0.494 2.99 - 3.42
2.5 0.471 3.13 - 3.59
1 0.367 4.02 - 4.60
0.82 0.340 4.34 - 4.97*
0.7 0.317 4.65 - 5.33*
0.6 0.295 5.00 - 5.73*
0.5 0.269 - - 6.29
0.4 0.237 - - 7.14
Note:
———
5Amp PS - a 5 amp AC-plug Power Supply
“*” - denotes calculated and projected values. These were never measured. In fact, all values were first calculated using measure of a stock value, then some were confirmed with actual measurement. Variance was in the tens of milliamps, close enough for confirmation of a general trend. Those with the “*” were never confirmed with actual measurement.
Requiv is the equivalent resistance of three parallel resistors.
I settled on using a 1 ohm R10 in that third slot. Of course, the Trustfire 26650 could not supply any high current above 3amps (3x 26650) and cut off.
Here’s a picture of that third resistor.
Here’s when it’s all pressed together to fit in the compartment.
I believe there’s several classes of users, segmentable by the length of time they would need the flashlight to turn on. Fishermen, for example, who would need extended run time and upward of 10min turn on, would be better off with any stock driver board because battery life would be longer and heating would not be such a serious problem.
Patrolling, on the other hand, would need flashlight to be on just less than 60 sec each time. These folks can benefit from a simple resistor mod of the OEM board to get much more light. Tail cap current tells the story of output light, close enough for “government work”, assuming board efficiency stays relatively constant.
With the 1 Ohm resistor (0.5 watt size) added, the resulting current is about 4.6amp. That gets hot much more quickly outside of the flashlight head. While I would have to assume that driver efficiency dropped, this is a quick way to get more light, probably just over 4,500 lumens as compared to a KD-board mod’d J18 (5,000-5,500lm) with Tom had posted earlier. I’ve no set up to measure light, so I just extrapolate from what others said, since I doubt my eye can really differentiate the benefit difference between 5,000lm and 5,500lm output anyway.
