Mod: LuckySun F3X

Flashlight Modding and DIY Parts
1

I got this light from what I think is the Luckysun/Nico Nature factory store on Aliexpress for $29 shipped, I was curious about it, I had not seen any teardown pictures yet even though it is around for two years now. The idea was as a host for three XM-size 400nm UV leds for a purple monster, but upon arrival the host seemed a bit too nice for that. Actually the head of the F3X was different from the photo's, it lacks the cut-aways, I think it looks better without them:

Then I thought, because the light is delivered with an extension tube for 2x25650 cells, it would be nice to build a triple Nichia 144A light, but I got tired of the thought to have to build a custom triple board for it, and a zener-modded driver which I am not very fortunate in building (thusfar: one succes after tedious work, two fails).

So for today's mod it was decided to use just use XM-L(2) leds, but everything different from stock:

*I used three different XM-L2 leds: cool white (unknown specs, robbed from a SWM T25C), neutral white (T5 5A2, from Fasttech), and warm white (T4 7A, from Simon)

*the stock aluminium triple ledboard was converted to DTP using an ancient pre-Sinkpad method, not sure who invented it but at least I have seen comfychair doing something similar a few years ago. I had never tried it before and I can assure you it was nice to try it once but this was the last time :tired:

*the driver was cleared from components and used as contact board for a BLF-A6 driver. The batt+ was a direct wire from the battery spring to the BLF-driver, through an existing via.

*bypasses on tail and driver springs

*blue tailcap to celebrate a succesful mod :party:

I started the mod at half past 8 in the morning and it was finished at half past 2 in the afternoon, 6 hours of continuous modding .

Here we go:

I started with the tail spring bypass. The light has a nice fat Omten on a decent (but not perfect) PCB.

It took a while to realise that the F3X has a screw-in pill that screws out towards the top of the head. there was nothing to get a grip on so I drilled two small opposite holes on the edge of the pill and managed to screw it out with needle-nose pliers (no picture of the pill, sorry).

Next step was to thin the ledboard from 1.7mm to 1mm. The conversion needs a 1mm copper plate under the ledboard, and the head dimensions of the F3X are so precise (which is good) that the extra mm of the copper would prevent the bezel from screwing tight and it would ruin the waterproofing (o-ring would not be pressed on). Forty minutes of sanding (by hand) later:

The domes were used as handles but they were gone after a while. (the gooey is flux-remains with rubbed-in aluminium powder)

The leds were soldered off and 3mm holes were drilled in the thermal pads on the board. A 1mm thick copper disk was made to be attached to the underside of the board, and a bit of copper was filed into shape to later saw the fillings for the holes off.

Three tiny copper bits were sawn and filed in shape and then hammered in the holes from above. The anvil was a flattened piece of cast iron, the pin punch was a piece of welding iron which happens to be 3mm diameter.

The underside was sanded once more and on top solder was applied to restore the solder pad.

It does not look pretty but everything luckily worked fine without shorts.

Time for reflow, I love watching reflows so I'm sure you like it too :-) :

Now the driver. The F3X has a large 25mm driver that looks very well designed, the coil is because it can handle double the voltage as well when using the extension tube:

But it has a horrible low PWM frequency, an impossible mode order (high-med-low-strobe-turbo-SOS ) and the output on high is no more than 1000 lumen which is not acceptable for a triple XM-L light. So I cleared the driver from components and piggy-backed a BLF-A6 driver:

I dry-tested the driver and it worked. To be honest I'm having a very lucky day because during this entire mod no major disasters happened, this is not common!!

Btw, there were numerous small mods done to make things fit that are not described in this post (such as: make a small cut-out in the plastic driver covering thingy to house an extra solder blob on the driver's batt+ pad).

Assembly worked well too. The finished flashlight:

It works and it works well. These are not top-bin XM-L2's and the output (on a Keeppower IMR 4200mAh) is still a respectable 2730 lumen after 3 seconds, 2510 lumen after 30 seconds, 2100 lumen after 5 minutes (overriding the step-downs that the BLF-A6 driver automatically does) after which period the light was still not ridiculously hot. I like the stepdown of the BLF-A6 driver in this application, because of it I can lend this light out without problem, at half the output (still 1300 lumen!) it never gets too hot. The current at highest setting on a fresh battery is 9.1A, which is about perfect for 3 XM-L2's. The efficiency (this Keeppower battery is 3.8V at 10A after 30 seconds, see HKJ's charts) of this light is thus about 73lm/W which is rather good for a light at 2500 lumen. The efficiency is higher of course on the lower settings when the driver just uses the 7135 current regulator.

As said above, the beam is incredibly nice, a good resulting neutral tint (±4000K) and look at that hotspot! :

(the flashlight was 2 meter from the wall, at larger distances the beam is not different) The throw btw is 25kcd on highest setting (measured after 30 seconds, at 7 meter) which is not amazing, but you get that brightness very evenly spread over the substantial useful hotspot.

Very close to the wall you can see what three leds with different tint do in a triple reflector :-) , this is not anything that is relevant in actual use.

I'm really happy with this flashlight, perfect for camping: a small headlamp for close-up work, this light for everything else (the BLF-A6 driver still rocks!)

Thanks for reading! :-)

2

Huh, I tore mine apart almost a year ago. Figured no one cared much, else I would have taken pics. My head has the cutaways, and the MCPCB is red. XM-Ls only.

I had the idea of doing 3x XHP50 LEDs. Not much thermal mass, so it was just meant to be for high-output fun, but lost interest.

3

Nice! I still like the look of that host, I’m a fan of multi-emitter reflector lights

4

Thanks mate awesome job. I have been thinking of doing this to one of these. I like the look they look like a bigger D80.

5

Very nice.
Cool vid, you have a new subscriber.
First I have seen that DTP method, being relatively new to this.
Been curious of mixed emitters and again that is the first beam shot I have come across with it done.

Thanks for sharing.

If you have any other pics of the light apart I would like to see how it’s made so to speak.

6

Nice work Jos! Excellent end result, good thermal management and the mixed tint is right down your alley.

I had someone ask me about this light recently and I found it to my liking so I ordered one, about a week ago. Should be here in the next week I think. Cool to see how you went about upgrading it, I’m sure after a day’s work the pride factor really kicks in as well, that was always a big part of it for me, to have worked around the disadvantages and ended up with a light that is really what you wanted it to be in the first place. Always a good thing right there, big plus for the hobby for sure.

:beer:

7

OH, VW, TK likes low output and high CRI so she worked on figuring out the exact bins necessary for a triple to suit her needs, quite a while back now. She was really happy with it, like Jos is with this one.

The only one I ever mixed was, ironically, a D80 that I made into a Quad XHP50. I used 2 cool white and 2 warm white. That one ended up really nice too and had such an interesting look about it. lol

8

Thanks for the thread djozz. Nice to see a mod thread like this which seem to be far and few these days. You’ve done a terrific job with the DTP mod. Your another who has more patience than I. :slight_smile:

9

Nice light. I like the size and form factor. Did you get a chance to measure numbers in stock form?

10

I’ve been looking to buy this flashlight for a long time now. I think it would be excellent with Hi CRI Nichia’s inside. Great mod with DTP-ing the MCPCB. I love everything about this build, it is a proper BLF style mod. Budget flashlight, scraped parts and lots of skill, knowledge and time invested to make it work. Great job djozz :+1: .

What solder paste do you use?

11

Thanks, it is the best form factor there is I think. The output stock was almost exact 1000 lumen (forgot the actual number, just remember it was very close to 1000), regardless using 1 or 2 batteries. I did not measure the stock throw, but since the optics and type of leds did not change, you can just derive it from the lumen difference: 2500lm/1000lm=25kcd/ 10kcd.

Thanks, yes today’s stock lights are easier to mod (standard driver size, standard ledboards) than these older models, the process indeed felt a bit like going back a few years. The solder paste was budget too, and it works great, I just have to buy a new pot every year because it dries out over time: https://www.fasttech.com/products/0/10003546/1261003-chips-repair-tool-soldering-paste-grease

12

Beautifully done djozz,
I have been talking to the product manager at Lucky Sun for some time now and he has agreed last night as matter of fact to give BLF members a 15% discount at their LuckySun / NicoNature AliExpress site, which by the way they have 2 brands, LuckySun and NicoNature for those who didn’t know, and their store is here: NicoNature
That would bring the F3X down to about $24 or so,
We are still talking about the details on how to go about getting the discount but as it is now you would just go to the store and send a message through the store and let him know you heard about a 15% discount for BLF members and can say either T18 or Gary mentioned it and then he will do any one of a number of different ways he sent to me last night to reflect the discount on your order and that is another issue I am not clear on yet, is the discount on a light or the order? I will be checking on that.
This all came to be last night so I haven’t posted anything formally yet since there’s still some details but thought I’d mention here first.
I also hadn’t even noticed that round head F3X until djozz took his picture here and it’s clearly on their site as the first picture of the F3X and then the D-80 style head is next one down in the pictures, so I asked about those heads and was told there still are a few of the D-80 styled heads and the others are round like djozz’s here, just thought I’d mention being I like the D-80 style a lot.
WOW such a really great mod djozz… :+1:

13

Hi T18, good job arranging that 15%, I like the Luckysun lights :slight_smile:

If you have contact with the product manager, could you ask if they can do an update of the F3X?, I think it is a viable model. It has two-third the capability of a SRK in a much better form factor. What I’d like to see (not surprising):
*update of the led type: XM-L2 or XP-L(2)
*DTP copper board
*more power through the driver (the body can handle it)
*at least 4KHz PWM
*better user interface, no blinkies in the main sequence
*perhaps an integrated shelf design (like the D80) instead of a design with a pill.

14

nice read

thanks djozz!

15

Yes Sir, that is all potentially very doable…
I would very much like to speak with you djozz, would you mind if I PM you .?
I am at the moment having one of those days, so I might need to PM tomorrow
(Oh, it’s Thanksgiving Day tomorrow) maybe PM later tonight or day after tomorrow, but I seriously do want to talk with you … :laughing: :+1:

Edit: Oh Ya, And Thank You by the way djozz, that was real nice of them for sure,

16

Yes, a PM is fine, it is late in the evening here though, so you may not get an immediate answer.

17

My Lucky Sun F3X came today, it’s got the cut outs across the fins like the D80, which I’m very happy with. It tests out at 2.54A and 1024 lumens, pretty lousy for a triple really.

That said, I will, of course, strive to achieve better results. :wink:

Edit: Knowing that the UI will prevent keeping the stock driver, I wanted to see what some changes in the sense resistor bank would do. So I stacked a single R056 onto the bank of 3 R200 resistors, did top and bottom spring bypasses with 18ga Turnigy wire and bumped power from around 3A to 3.68A. (I measured 2.54A originally but it may have been in high, I was forgetting the Turbo sandwiched between Strobe and SOS)

So then I stacked a second R056 and it now pulls 6.10A in Turbo and does 1825 lumens. So 2 R056 resistors and a couple of short bits of wire and it’s nearly doubled it’s output. Interesting. So will it maintain this with 2 cells? Or would that fry it?

I’ll be getting some of Texas_Ace’s new drivers with Narsil on them in the coming week or so, I’ll wait till I have one of these new drivers before I go any further and kill it. :wink:

By the way, I’ve been using a well rested Efest light purple 3500mAh 26650 at 4.16V to begin with. Think I’ll charge it up to full capacity and see how that affects the F3X now that I’ve made the bumps…

18

Wow Sounds awesome that just two chips and bigger springs woke that baby up.
So what’s next? More chips? Change out the emitters? Dedome them? Change out driver when the Texas arrives?whats the UI like? Sounds awkward that u say turbo is inbetween strobe and sos.

19

Blueb8lz, mind that the ledboard is non-DTP, that ultimately limits what you can do. It would be awesome if Luckysun upgrades the L3X with a copper-DTP board, I really like this optic and beam.

20

Nice work! That DIY DTP board is pure skill and commitment.