UPDATE AT THE END OF THIS POST
I present you my latest flashlight. Its been a while sience I uploaded a mod, I hope this one will make up for it! The reflector design is inspired by Old Lumens, the heatsink and active cooling design was all my ispiration. I wanted to build an active cooled flashlight, as raw power is not everything if you cant use it more than 10 seconds. Its a little “Frankestein” looking, some will find it ugly, personally its not my favorite looking piece, however 100% innovative…
This time I have some photos of the building process too:
The host is a SRK. I used a second tube to accomodate the 8 cells.
This is the template I used to drill the holes for the heatsink. Firstly I drew it on a piece of paper and then scaled it down with a computer and printed the right size. In this way it came out more accurate and the work of drawing in bigger scale was easier.
114 holes for 114 rods, of which 64 go through all 3 copper plates.
Drilling 1mm pilot holes, and then enlargen then to 2.9mm for a tight fit with the 3mm copper rods.
The heatsink is composed of three 2mm copper disks connected with 3mm copper rods. In the middle disk I cut a 30mm hole to accomodate a 30mm fan, normally used to cool RC cars. It reaches a maximum of 23.000rpm, it moves a huge amount of air. There are videos of it on youtube. Its called WTF 30mm.
The switches and resistors are used to regulate the speed of the fan. I chose 3 speeds that thought were useful, one quiet, one middle and one almost max.
The reflectors are from KD, 36mm in diameter and were cut with a hacksaw and shaped with a file to fit together nicely. Epoxy was used to glue them together.
This is the driver I am using with Narsil firmware/ramping, 0.3mm copper sheet solderedused on the spots where the cells and carrier are contacting to prevent wear on the gold contacts. It also increased the mass of the driver, improving its heatsinking.
And some numbers…
The design of the heatsink allows a clamp meter to be connected direclty at the 13awg cable that goes to the leds. I am reading with 8 LG MJ1 3500mah cells almost 40amps, which translates to 10 per emitter and theoretically almost 20.000lumens. I suppose OTF I get 18.000lumens, maybe 17.000. The surface of the heatsink alone is calculated to 380cm^2 or 59in^2. Roughly an area 20cm x 20cm, not bad. Heat at those levels (40A and 8.4v) is still a problem but active cooling helpes immensely on middle levels.
Measurment of xhp50.2 from djozz here on this forum:
Wall shot next to a C8 with XML2. C8 on the right CW 3amps. Frankestein on the left NW around 5amps. Brighter and bigger hotspot.
Hope you like it! Comments/advice/questions always welcome!
UPDATE………………UPDATE………………UPDATE…………….UPDATE…………….UPDATE………………….UPDATE……………
Beam shot location:
Beam shot video of my flashlights:
[video:]https://www.youtube.com/watch?v=\_Dv9pXU5oQ0[/video]
Active cooling demonstration:
[video:]https://www.youtube.com/watch?v=F9Z30fD9TmY[/video]
For further information please check the video descriptions.
Some numbers:
From 23C to 52C in turbo 41sec without fan. With fan 50sec. Ambient temp 23C. (indoors)
From 7C to 52C in turbo 1:13min without fan. With fan 1:30min. Ambient temp 7C. (outdoors)
From 23C to 52C in 50% 2:23min without fan. With fan 4:41min. Ambient temp 23C. Sabilizing around 55C.
So in turbo the difference is very small, but in 50% which is more than 8000lm it almost doubles the runtime, and please note it was indoors. Outdoors I believe you can run it below 52C for ever at 50-60%.
As I say in the title I would be willing to sell this flashlight if I get a generous offer. I put a lot of work in it, around 60-70 hours and as a reference the matterials alone costed me more than 150$. If you want to make an offer with PM feel free.