I have just finished reading ohaya’s thread. Yes it is quite disappointing that this driver might not be able to be resistor-modded and deliver high output current. The other components like the diode and the FET may not like it.
3 possible scenarios we could have here:
Maybe we should hope that the manufacturer of this Uniquefire 1405 would use better components on the driver. ohaya’s driver has R200 resistor, whereas your driver has R120. Hopefully the other components are different (in a good way) too.
2. Finding another 16.5mm buck driver, but this is not easy at the moment. Most of the better buck drivers are usually large in size.
3. Forget all these buck drivers and go with the BLF17DD driver or 7135 based linear drivers - i.e. Nanjg 105C type of drivers. This way we cannot use 2 x 18650 anymore. A dummy cell can be used together with a real 18650 in this format. The downside of this is we do not have constant-current regulation anymore, which is the beauty of buck drivers. But the bright side is we are quite familiar with Nanjg drivers thus we can easily boost the output current, having more flexible mode selections and also flashing your own firmware.
What is the output of my driver with the R120 resistor with two 26650’s?
What resister would I piggy back to add .5 amp more?
Are there any 7135 based linear drivers that accept 8 volt input?
I am afraid you won’t see 7135 based drivers working with more than 1 18650. That is the way they are conceived to work. If you increase input voltage you will suffer from reliability issues to very poor performance. You can find ways to overcome this, using an buck part inside the driver but this is not economical, increase complexity and need more space.
I am making some experiments trying to use amc together with a cccv driver to have as much controll and a smooth output as possible just for funn. Normally it should work with 1,2,3 or 4 batteries in series and have a very wide current range from 0.38 A to 8A.
Downside? Is expensive around 30 $ and very big. Aso will need to find out total performance of the system, maybe 30% are loses… for this i am not sure. but it can be fine tuned.
Hi mholdenattorney, there is no way I can guess the current draw of the flashlight by knowing the resistor value alone, unless I have one in my hand and measure it with DMM. There are just too many factors playing in it. I am not sure if ohaya has figured out a way to boost the current draw with this driver, from his last post it doesn’t seem optimistic though.
I know people around here has figured that changing the zener diode can increase the Vin of the 7135 driver, hence the Nanjg driver can accept two 18650s, it is an idea of using different value of zener to lower the Vin down into the voltage where the MCU can handle, but AFAIK they only use this with MT-G2 because Vin = 8.4V and Vout = 6V, the voltage difference is not too much there. However if using the zener-modded 7135 driver with XM-L2 the Vout is only 3.4V or so… the difference between the Vin and Vout is up to 5V! So that could be an issue there since 7135 (Nanjg) drivers are not buck-driver but linear-driver, they can’t buck the Vin down into Vout but they can only kinda “burn off” the excess voltage. This way even if it does work I highly doubt the efficiency of this setup will go more than 50%!
There is a thread about this setup and you can read it here.
Did you see the pic in this post in that other thread?
If I recall, that was with a R100 stacked on top of the original R200, and with the replaced schottky diode (but hadn’t replaced the FETs), so 4.45 amps at the emitter with 4.7V Vin and 4.5 amps Iin.
Looks like it might not be too hard to cut off the driver tower and bore out the driver cavity enough to press in a larger diameter peice of copper or aluminum tube/pipe.
I want to put an MT-G2 in one of these. What do you think the chances are of getting a 20mm star in there? Is there enough material in the pill to open the hole up?
That’s exactly why I want to try the MT-G2! Haha I have had one sitting here for ages along with a suitable driver but have just been waiting for a good 2x 26650 host to become available.
I think I will just buy one of these anyway and see how it goes. I might be able to bore out the whole centre of the pill and machine down a piece of copper bar to press in there.
It will work great with many 26650 batteries, but I would be careful with the Keeppower IMR 4200 mAh, I fear that that combination will lead to well over 10A. It may be the way I go with this light :evil:
I placed the order for mine today and opted for express post so hopefully it doesn’t take long to get here. I have the MT-G2 and driver already here. Will be interesting to see what I can do with the pill. I hate aluminium ones.
Maybe if there is enough people interested someone can build up a copper pill for it. Might be able to open up new driver options that way too. But then your taking a $35 light, adding a $20 pill, say $7.50 for an emitter and star, and $10 on a driver... now you got a $75 zoomie LOL
I got the package in from Fasttech, and they delivered the wrong one! The SKU on the cardbox box is the one I ordered but it contains the Uniquefire UF-1406, the smaller 2x18650 zoomie! I opened a ticket and I'm sure it will be sorted out, but it will be -I fear- a month or so before I actually have the light I ordered
This is what I got, I might as well give some info on this one, it is a hell of a light, but it is just not the UF-1405 :-( :
The flashlight has a nice size, a great build quality: perfect ano, thick aluminium everywhere, ano'ed tail threads, lubed.
A small dissection of the optical part:
Now that is great optics, yeah !! short focal length lens, the diameter in actual use is 47mm! (FYI, UF-T20:32mm), with the head diameter of the flashlight used to the max :-) . The tediously slow focussing goes a bit through the focal plane of the led die, this improves the beam compared to the ugly sharp focus, without loosing throw, nice.
The current on high is plain disappointing: 0.9 A (from 2x CGR18650CG IMR batteries in series), that should translate to less than 2A through the (old gen. XM-L) led. Terrible PWM. I need that awesome BLF 17mm buck driver that is still in developement!!!! Despite the low current XM-L use, the throw is close to 40klux@1meter, promising!
!! short focal length lens, the diameter in actual use is 47mm! (FYI, UF-T20:32mm), with the head diameter of the flashlight used to the max :-) . The tediously slow focussing goes a bit through the focal plane of the led die, this improves the beam compared to the ugly sharp focus, without loosing throw, nice.
