Andúril 2 coming to Sofirn - The general Sofirn development thread

You seem to confuse heat (thermal energy) with temperature. These are related but different.
For sustained operation, LED temperature = surface temperate + thermal resistance * power dissipation

Adding mass in form of wax, (that is: one that doesn’t contribute to thermal conductivity of the light) would slow down temperature rise before the peak is reached and have no effect once the temperature peak is reached.
Adding mass in form of alu (that is: one that improves thermal conductivity, but for well designed lights just marginally) slows down heat rise and (marginally) improves efficiency at peak.
Adding insulation layer reduces sustained performance. When the layer is too thick it’s indeed an issue. However if done right it’s not bad at all. If you start with a good host that never heats up the LED to more than say 80 C and skin to 50C and insulate flashlight skin in a way that increases LED temperature to 100 C at Turbo w/out chaning skin temp you end up with a light that:

  • is still reliable
  • has way longer Turbo
    • temperature delta near LED is 33% larger, improving heat storage there by 33%
    • temperature delta near skin is 66% larger, improving heat storage there by 66%
    • temperature delta at not-the-hottest points of the skin and other thermally-distant points is more than 66% larger
  • assuming that Turbo power is 4 times larger than sustained, runs the LED 5 C hotter during sustained operation which has marginal effect on efficiency.

Note that by making the insulation smart:

  • high emissivity
  • with thickness that varies to equalize surface temperature at touchable points
  • which is not present or has marginal thickness on untouchable points, maximising temperature there

you can actually improve heat shedding and increase sustained power dissipation. You still take the small efficiency hit but nevertheless sustained output should be higher.

Yes its a big difference with fins. There is a custom C8 head from kiriba-ru in this forum named “C8TT triple heatsink head”: Low-cost copper pills, spacers, optics, drop-ins (Updated 23/10/2022))
Here are some tests on it:
What did you mod today? - #6022 by contactcr
Convoy C8 triple with Kiriba machined head

Sorry, I’m not understanding most of what your describing. A lot of it sounds theoretical from a book. I’m not so book smart, I’m more old school, learn by doing.

About 20 years ago I started building active and passive air cooling systems for PC’s. Then I started brazing together pieces of copper and brass to make water blocks for water cooling systems, also for PC’s. Although I have experience with phase-change system’s using compressors and freon, it’s only from working on refrigeration products, not PC’s. I’m familiar with Peltier style cooling as well, but have never tried it myself.

Keep in mind that cooling a PC CPU is very similar to cooling a flashlight LED. Both have a small, but intense source of heat.

The specific type of phase-change cooling that you’re referring to is something I have no first-hand experience dealing with. I can only use my previous experience to guess what is going to happen. Maybe you are right and wax will work great. I’m just saying that, based on my previous experience, I don’t think wax is going to work well.

If you experiment with it, let me know how it goes. Good or bad, I’m sure there is something to be learned. :+1:

There is a plenty of similar flashlights, which can do about 800-1000 lumens, and they have a mediocre (at best) emitter and a simple UI (which is not matched enough for use cases), and that’s all.

We need to find things to differentiate this specific flashlight beyond that it haves built-in USB charging.

I think, rost333 told many useful ideas, let me add a few things on top of that.

My personal observation was, that when I started to show a few of my flashlights to muggles, for the first flashlight, they didn’t care about different CCTs and high CRI, but when I showed them different CCTs, the most popular combination for emitters were in the CCT range of 4000K-5000K (a few older people were felt themselves very good with 3000K as well). And, when I showed the first high CRI flashlight to them, they acted like - “really, it shows colors seemingly better” - “it is not that dull and harsh cold white, which I can get from most of the cheap flashlights” - “wow, this is beautiful, I want one, too”. So, if measured lumen output does not differ too much, high CRI still can be a win, when it comes to human perception.

So then, I would suggest Luminus SST-20 4000K 95CRI, if a more defined hotspot is desired
and I would suggest to get Samsung LH351D, which is more efficient (I don’t have exact numbers, maybe by 15-20%), but noticeably floodier - and there is a little tradeoff in CRI, but it is still 90. It is also available in 5000K and 6000K.

Taking a look at the UI, the current UI has these:
single click to ON/OFF
long click to cycle modes: 10 lm (Low) - 200 lm (Medium) - 610 lm (High)
double click to full power strobe

Jump between Low and Medium is too big. Low is not enough low.

I would suggest something like this (output number suggestions for SST-20 4000K 95 CRI):
from OFF/ON: single click to ON/OFF - resume to last memorized output level (Moonlight is also memorized, but not Turbo and Bike Strobe)
from ON: long click to cycle output levels (change level every 0.5 seconds) : Eco (3 lm) - Low (25 lm) - Medium (150 lm) - High (500 lm ~ 66% of current in Turbo mode, for continuous use)
from OFF: long click to enter Moonlight (0.3 lm) - from here, long click to start output level cycling from Eco level
from OFF/ON: double click to Turbo (~700 lm) - timed stepdown (3 minutes) to High, single click to last memorized output level - double click will return to Turbo any time for another 3 minutes
from OFF/ON: triple click to Strobe - single click to last memorized output level - another triple click to Bike Strobe (how it exactly works, needs to be defined later, but having this mode should be definitely useful, as this is an EDC light)

Having this UI, this flashlight would have 6 well spaced output levels, which don’t need to be cycled in full length, as two of them are ‘hidden’, so fairly quick output level selection is still possible.

The reason for the fins is to increase the surface area. You can take a large smooth light and a small heavily finned light and they can have the same surface area. Of course, the smaller heavily finned light will be lighter and easier to carry.

The more surface area, especially near the heat source, the more air gets exposed to it. The more air exposure, the more heat that gets radiated away from it. So a small light can shed heat as if it were a bigger light by having a lot of fins.

Of course, flashlight manufacturers want to sell lights. They will reduce or eliminate fins to make it look nicer or feel better in the hand in order to get more sales.

This is worth repeating. I can see variances depending on power/LED/size configurations for the specific light, but if Sofirn standardized on a UI like this and matched with good LED and tint options, they could take over the market.

I guess I built the Ham’r for nothing. Nobody gets it.

Fins, and mass, make the light viable. 17 emitters doing right at 26,000 lumens… only viable due to the mass of the 4” 6061 Aluminum head and the extensive use of cooling fins. Does it get hot to the touch? Of course it does! It’s transferring heat to the air, how could it do that without bringing the heat to the surface for the air to remove? I’ve run it over 20 minutes on Turbo, blistering hot on the outside, emitters still running fine. Isn’t that what it’s all about? Survival of the components?

Did all that work for Sofirn to see their Q8 pushed to limits unimagined and it’s all for what? Think they’d actually send me the extension tubes to test at extreme levels, which is of course why I build the dang light in the first place! Do I have extension tubes to test? Djozz does, but of course, I don’t. And so it goes…. I give up

Dale - I agree, the advantages of finning have been well proven long ago with the TR-J20 as a good example (i.e. chunky monkey here), FlashPilot being the early proponent of these designs. I sure hope Sofirn didn't stiff you on promises of proto testing of the carriers.

Sofirn crew, ever consider offering some lower temp lights, particularly for your floodier models? (i.e. 3000k, 4000k)

Oooooh, a C8FW!!

Sofirn, would you consider making a small zoomie?

I have a feeling there’s a big hole in the market. I believe the smallest quality zoomie under $30 is On The Road i3. There are smaller ones from Led Lenser but they either are very weak or cost more. Similarly with Coast.
If we want size smaller than i3 and price lower than Led Lenser we have pretty much only $.5-$2 stuff which leaves a lot to be desired.

At 16340 size there’s OTR i3 - good quality, not cheap but reasonable, not super compact but not very large either. You should be able to beat it in value….but if you go down with size you get pretty much no competition.

At 14500/AA size zoomies tend to not be small, usually diameter is larger than i3 despite smaller cell. I’d rather take i3 than any of them.
At 10440/AAA size there are a a few reasonably compact offerrings but typically of low quality
At 10180/10250/10280 size there’s nothing

I could give a more concrete example:
I think a quality 10440/AAA sized zoomie with optional 10180 tube would be a hit. Available with 2 classes of LEDs, for throw (f.e. Osram KW CSLNM1.TG) or for high light quality (f.e. Luxeon Z ES / Luminus SST-20 W / Nicha E21) to serve well both those that love tint and those who prefer throw.

But I think that pretty much anything in that range would have a good potential.

Why would anyone buy a zoomie knowing that they have terrible efficiency? I don’t see anyone buying it. What’s the appeal in it?

I recently bought an OTR i3 and if it had a better UI I’d be carrying it daily! :wink:
The appeal may be a remnant of the “old” idea that zoomies were “the thing”, or simply the push-pull to mess with the light! :crown:
I still like the zoomies! Not everything has to be efficiency related and the zoomies still have their place in the flashlights world :wink: My opinion!

First, there are 2 kinds of zoomies, based on TIR and aspheric lenses. TIR is likely not feasible for such project due to poor lens availability. Maybe I’m wrong about that and there’s just the right lens that I haven’t seen. I’ll talk about aspheric ones though, they are easy to source.

In flood mode they have good efficiency, from about the same as TIR or reflector to marginally worse (they take a larger hit when the lens is uncoated). At the same time they tend to produce smoother beam…which is sometimes better and sometimes worse. Personally I also love the sharp beam cutoff though it’s not a commonly expressed sentiment. So for flood….I wouldn’t call them better or worse than TIR, reflector or mule, it all depends on preferences. Personally I like them more.

In throw mode, yes they are very inefficient which means that spot size is small. Throw numbers are good, often better than that of reflector lights. Because they don’t have any spill distracting your vision you usually see farther with aspheric than with a reflector. So…despite very bad efficiency I wouldn’t say they are worse throwers than reflector lights. They are different. Personally I don’t really know which I like more, it depends on the situation. Super narrow beam is not my style so for large throwers I tend to choose reflector and large LED. But even 18 mm lens with 1 mm² LED won’t produce a super narrow beam.

And, obviously, the ability to have both throw and flood in a single light is just awesome.

I’d really love to have a nice zoomie on my neck, now I often use a fixed aspheric (Utorch S1 Mini).
Maybe I’ll end up with some cheap AAA one. Maybe with OTR i3 though it’s too large for permanent use.

The only ‘zoomies’ I have are the Cometa & Jaxman Z1 and I actually like them quite well. I like the fact that they can go from a ‘wall of light’ to a tight hotspot & back again. Very versatile imo.

I’d be in for a mini type version of either one, AA or AAA size would work for me.

A nice buttery-smooth flood with nigh zero artifacts except maybe around the edges.

I would’ve loved my SK98 if I could weld the head to a permaflood position. Absolutely hated The Bat Signal when zoomed.

Hell if I can find my “match-modded” MiniMag with ~20mm aspheric lens in front. That was a thing of beauty.

But yeah, the hideous drop in efficiency when zoomed just irks me like gravel in my shoes.

Yeah, but we are talking big differences here, not small percentages.

The only zoomie I have is the Cometa. I measured 810 lumen on wide angle. As you narrow the focus the output drops to 270 lumen. The battery is still drawing the high amps and the led is still generating lots of heat, but you only get a fraction of the lumens. Hmmm, it’s exactly 1/3 the output so that’s a 66% loss in brightness.

Oh yeah, I also have a J5 Tactical light someone gave me. With a 14500 battery it measured 92/50 lumen. That’s only a 45% loss.

So losses aside, you still find it a useful type of flashlight?

It must be worth something that that 33% of the light is projected a football-field away. Mind that in a reflector light a comparable or even smaller percentage ends up in the hotspot, so the question is: how much is that spill light worth? The answer differs with application.

Yes. Not only that, but there are ways to make it better, right? Doesn’t the quality of the lens have a lot to do with it? Also, it has been mentioned coating the lens. Another possibility is to use a multi-lens arrangement and/or a Wavien style collar. Either of those would help ensure that more light makes it out the front. That would make the light more unique as well, which Sofirn has already mentioned as a goal.

I’m for the idea of making a little AA or AAA high quality zoomie light. I don’t want it to look too bulky, and not tacticool at all either. No SK68 body style. Make it nice and sleek. Maybe an internal twist zoom (which would work very nicely with a multi-lens arrangement). Bonus points if you make it look like a FW3A with a small “camera” zoom lens on the head (but with only one emitter, of course).

A good aspheric zoomie is about the perfect light - tight beam or as pure a flooder as you can get, anywhere. Using a reflector light for distance is ok if you don't care about lighting up the peripheral area, but when all you want is light at the target, the reflector lights are a total waste, so you may see the lack of spill from a zoomed zoomie to be wasteful, I see the spill out of a reflector wasteful in throwing light where I don't want it, even worse, bothering the neighbors, distracting wildlife, attracting attention when you don't want it, etc.

In flood mode, it's the perfect flooder - no hot spot whatsoever, the better ones have a wide field. I prefer one handed operating zoomies, smooth sliders as opposed to twisties. The Wowtac A3 here is close to ideal with an e-switch, but I've been unable so far to remove the bezel, guess it's glued. Many zoomies are inferior quality, cheaply made, poor aspheric lenses, etc., so it's hard to find a decent quality one, and one that also takes advantage of the head diameter to max the lens width. The B158 is a great one in regards to the optics, and built well, but it's a tail power switch.