Air Cooled 4x XHP50.2 UPDATE: Videos, Willing to sell

Absolutely awesome build!

Wonderful work with that heatsink and active cooling. OL would be proud! :sunglasses:

How long can it run on turbo with the fan speed set to high?
Got any outdoor beamshots at turbo?

Thanks for the info. So the electrical contact for batt- is done only by the 2 tubes connected with epoxy? Since I have a somehow similar mod in my mind I wonder if over the time the pressure between the 2 tubes decreases and the contact resistance rises.
The tubes are nice, they look similar to the Q8.

Deserves a bump.

[quote=Flashy Mike]

Yes you are right, over the time it could happen. You also need to have both surfaces very smooth and gapless before gluing , and use some weight while it hardens. The current doesnt flow through epoxy and the screws but through the exposes aluminium where the 2 tubes meet.

Now if the tubes loosen with time and I lose contact, a possible solution is to drill one or more small holes exaclty between the 2 tubes(in the gap) and insert a short piece of singe core copper cable or similar conductor (with a tight fit) to reconnect the two parts.
If you find a conductive epoxy, it would be the best solution in first place…

To the other memebers asking about temps and beamshots, until now I didnt have the time to use the flashlight enough. I will try in the next days to do it, and write back.

my reaction was WTF :open_mouth:
same as the brand of the fan you use

There are other techniques that assure electrical contact between 2 SRK battery carriers.

They can be threaded on one side, pressed fit and pinned together with roll pins (4) of them and then epoxied.

You are right! I have done this in another 8 cell project, the last one in my signature. Its 1s8p with 2 tubes. This time I wanted to avoid the conencting ring for a smoother look. It is more practical with the ring though, as you can unscrew it if needed.

You can still roll pin, or get really fancy and use brass pins, and on the PCB side, use the 4 PCB mounting holes, drill them out for the pins, press together and epoxy. You just have to drill and tap M2.5 or M3 for the new PCB location on the one end.

Well we need a BLF Museum of Fine Flashlight Art! :wink:

This one needs to be in it!! :heart_eyes: :+1:

Very nice :+1:

Yeah. I guess I would choose the option of screwing them together with a threaded ring, similar to Kourtinoksylos’ previous mod, but the ring should have twice the height of the tailcap to fit nicely. It’s a pity I don’t own a lathe.

very very nice !!!

I dont have a lathe either. Just cut the plate of a tailcap like this picture, then epoxy the non threaded side to the back of first tube leaving the tailcap threads free so that the second one can be screwed.

I have seen your mod earlier and like the idea but still would prefer a ring of proper size which can be screwed on both sides and allows to separate the tubes with little effort later. But if I don’t find a fitting ring i consider to use your approach too.

All done by hand, no lathe at home, not yet…….

Haha with 1300gr=2.85 pounds it needs a backpack. It is a cometitor for the BLF GT in terms of mass.

I started to make some meassurments for the effectivness of the heatsink. I need to top up the cells between every test to keep the results consistent and this takes a lot of time. First results show little difference in turbo as we are dealing with 335W of power and the heatsink i built is definately not big enough.

–41sec to reach 51C without the fan, cells top upped, retested: 50sec to reach 51C. So it makes no practical difference in turbo.
Other levels are being tested and I will update the original post.

I think you could change your name to NL for (New Lumens) or maybe YL (Young Lumens)

If you want to sell it, as opposed to willing to sell it, you will get more nibbles if you put a price.

I know it hurts and it is hard to justify flashlight modding with $$ but that’s sort of the way a market works.

best of luck to you.

Thank you! I dont really want to sell it because I like it very much and air cooled flashlights are very very rare. Apart from that I put a lot of effort in it. But if I get a price from someone that will pay off the time I consumed and the uniqueness of the design then I am selling it. I think the one that will be interested in this flashlight will be able to estimate a price. Maybe I am wrong…

I cant put a price on it, because I dont know how modded flashlights are priced.
A very famous modder, sells for example a C8 with xhp50.2 thats works only with 18350s for 100$ while on KD its 29$ for 18650 version. Or a slightly modded Convoy L6 for 165$ if I remember corectly. So he is selling for 3 to 4 times the material costs for emitter swaps or improved driver, nothing special. His special items are for sale for more than 1000$.

Just saw your updated post with the youtube video. That is absolutely wild…sounds like a small turbine engine in there.

So I suppose the name WTF ( Wild turbo fans) fits perfectly to the fan lol. Thats why I selected 3 different speeds, on max it spins according to data sheet with 23.000rpm and it would be annoying to run always on full blast. Even my max fan mode is not the 100% the fan can push, I use resistors to limit it to around 90%.

Thanks for watching!