Would you be interested in a fluorescent yellow powder coated Convoy S2+ / C8? Updated

Sounding good. Just checked your instagram, nice pics!

Cool thanks!

Your assumptions are false and inaccurate. Ive already been down this road with several manufacturers trying to profit on this bad/potentially dangerous marketing idea. So I’ll copy/paste & mod my reply here:

I was a production manager for a precision high tech/high volume metal finishing company (where daily production volume is measured in tons of finished material and in thousands of pcs). FACT: powder coating aluminum, even down to the minimum acceptable thickness spec, will at least double the thermal retention capacity. This isnt false conjecture, and I have nothing to gain or lose by stating fact.

Background: In proving with aerospace engineering teams while powder coating aluminum material on a constant speed precision industrial automated line, several processes required a precision calibrated cool-down cycle before proceeding to the next reheat station in the production process. The line speed was automatically adjusted to maintain a precision target temp. From the data recorded (which is necessary to maintain and prove the production standard), bare aluminum cools at least twice as quickly as powder coated aluminum. This is also true (to a lesser degree) of black electrostatic applied paint and various wet coatings applied at only 35-40 microns (super thin). Dark colors typically radiate heat more quickly than lighter colors of the same formulation. We also experimented with custom formulations containing “micro iron balls” to help disperse heat, ala SR-71 finish type coatings.

So why is powder coating a problem with the lights your intend to coat and at the power levels you just stated? A typical C8 flashlight driven at 3A will get hot enough to burn your hand if left on in high mode. If it doesnt, it lacks a sufficient thermal path from the emitter to the host. Once heated, removal of the battery at that point will also quickly tell you the battery is VERY HOT to the touch… which greatly increases the chances of a cell explosion.

As a re-seller of flashlights, especially the Convoy C8 flashlights and similar (latest version with integrated shelf and 3A 8 x 7135 driver, XML2). If left on in high mode, several have failed in the field, because the heat build up is so great that it desolders the emitter from the MCPCB!… which requires a tear-down and reflowing the emitter back to the board). Sometimes it only melts the solder from the wires, but this isnt as common. This happens to roughly 1 in 11 flashlights. None of these lights are shelf queens and are heavily used by those who purchase. Tube style lights have far less surface area to dissipate heat, which is far more of a problem because they will conduct even more heat to the cell. A tube light driven at 2A will run far hotter than a C8 driven at 3A.

As has been proven dozens of times in just this forum alone, driving an emitter (even at moderate levels within MFGR specs) without a proper thermal path, severely decreases lumen output (which is also the case with plastic lights that have been tested here). The only good thing about plastic lights is that they do not transfer heat to the cells, which lessens the chances of an exploding lithium cell. Heat also kills lumen maintenance (mfgr. rated life of the emitter as measured in hours)., not good.

This has nothing whatsoever to do with the subject, but since you mentioned it: SOME brake calipers engineered for street applications are finished in electrostatic powder or wet finished “paint” (which I have processed several thousands for major OEM’s). It is for aesthetics and ease of cleaning, not performance. Non powder coated alloy calipers dissipate heat far more quickly than powder coated ones, which is why purpose built racing applications are typically never powder coated.

With this in mind, intentionally doubling the thermal load of a cell potentially jeopardizes the safety of your customers. Regardless of how appealing the color might be to the user, overheating the cell can be very dangerous and should be avoided at all costs. I hope you’ll put aside the thought of your grossly inflated asking price for a moment, and reconsider the potential consequences of what you are attempting. Is it worth increasing the chances of your customers turning their (already hot running) stock flashlights into potential aluminum fragmentation bombs? This is exactly what you are accomplishing here. I havent even mentioned potential litigation from such an outcome, should a cell rupture.

- Please dont build and operate a small flashlight and allow it to run @6A until cell depletion, even while using a bare aluminum flashlight host. You will overheat the cell.

- Please be responsible and operate your cells no higher than the max allowable temps specified by the cell manufacturer in their data sheet. Less temp is far better for safety and the service life of the cell.

Good day.

Ooh… That bad huh?
Thank you for that important information.

So, actually many many lights out there would actually need some kind of overheating protection, even a black C8 with 8x 7135.

Wouldnt that be nice? Thermal throttling has already been implemented in many drivers as well as in some factory flashlights to help prevent such mishaps. Thermal control circuits also exist in most approved lithium powered consumer electronics, so its not a stretch to demand or expect it.
Also depends on whether or not you could successfully sue the manufacturer in the even of an injury, which would be nearly impossible with chinese manufactured flashlights & gadgets. Their outright lies, rampant counterfeiting and lack of moral trade ethics also remains mostly unenforceable.

How’bout glass bead retroreflective powder? :smiley:

That would be tres suave…

You could then leave out the battery…

Aauugh, you beat me to it…

…and how about those crazy people who demand 1000 Lumens or more from a 18650 cigar…?? :innocent:

I’m powder coating so people can have some nice coloured lights there’s not much profit in it for me, the profit is in building full lights. (Even then not much)

Doing a run of fluorescent lights for BLF is at the minimum cost I can get it for host/powder/equipment/shipping. So for £16-20 it’s not worth my time. But I was willing to sacrifice that.

So It’s an insult that you say “Grossly inflated asking price”

(£7/8 for the host, £3.95 shipping UK - £8.20 International, Powder, Consumables, acid to strip anodising)

That’s £16.20 to get it shipped internationally, before you even start, leaving £3.80 for materials listed above (for £20)

Maybe the USA is different but the UK is one expensive place to do things.

There is still issues running high power drivers in non coated small lights, 6A with an XPLHI etc. In a S2+ there’s still a chance of overheating. But people choose to ignore the risks to have a powerful light because most of the time it’s perfectly fine.

Last night I took a powder coated S2+ I had (only running 1.4A) and ran it with a Panasonic 3400mAh for 45 minutes on a table top in a 22C Temperature room, the cell was warm when I took it out. As expected, but no way near hot.
The light was hot but not uncomfortably so.
(I don’t advise doing this, but it had to be tested)

I say 2-3A because that is what I would run it at. But I see that may be high. Maybe I should drop that to 1A or below as the max operating Amps.

But Obviously you think people won’t be sensible and avoid running for long periods or at stupid temperatures. So the offers off the table

No more powder coating

James

I don’t know about anyone else here, but I tend to treat all modes over ~300 lm as turbo or burst modes (or, in small lights, all modes over ~30 lm). About the only thing I use three digits worth of lumens for (for longer than a minute or two) is biking, and I generally set that on a 200-lm mode with 2000-lm stutter pulses.

But I really enjoy having super-bright turbo/burst modes. :slight_smile:

An upshot of this (aside from the obvious ones of safety and long runtime) is that it rarely matters what material the lights are made of, since they’re typically running well below the power levels where heat is an issue. But when I give lights to other people, it’s generally only items which don’t have a self-destruct feature.

I don’t know if I want a bright yellow host, considering I still have a blue and a green I haven’t built, but it is at least compatible with how I use lights. It could be fun.

what does it mean exactly powder coated ?

Wow, I feel bad for 3tronics. They offer something unique, and the safety patrol comes out of the woodwork. Meanwhile, 5000lm pocket rockets get ooohs and ahhhs, for the 5 seconds they are on.

Frankly, I’d rather know the cute powder-coated light I just got can potentially turn into a road-flare in my hand if I leave it on too long, than be surprised at a most inopportune moment.

A method used to paint. Powder coating - Wikipedia

With all safety stuff considered (I think that flashpilot is over-protective of your customers, this is even sold as a host so it requires a flashlight hobbyist with knowledge to even make it into an actual flashlight, I’d reckon that the responsability of making a hotrod with xxx-fire battery and giving it to a layman is on the flashlight builder, not 3tronic’s), I’d still see the attraction of the fluorescent yellow S2+, and certainly not all my lights are hotrods!

James, may you reconsider making a batch of fluorescent S2+ lights after all, then I’m interested to buy one!

That’s not entirely fair though.
3tronics clearly understimated the thermal isolating properties of powder coating (and so did i b.t.w.).

And that’s why 3tronics shouldn’t be discouraged by the argument between him and ‘the safety patrol’.
I would like to have a screaming yellow host, and i’m not gonna put a quad on a FET DD in it.

:+1: that’s what Blf is about to me. Resposible madness!

Yes I would be interested in a fluorescent yellow powder coated Convoy C8 host.
I think you are doing a great job. And it will be an absolute stunner.

It is OK with me if someone is pointing out that there are some thermal drawbacks.
As far as I am concerned he (or she) cannot warn enough that these exist, there always will be new members on BLF.
But ultimately I am responsible for my own actions. Like walking around with a pocket rocket if I want to. Or two.
But I will NOT hand them out to friends or family. Not until I have talked to them about Li-Ion 1-0-1, and 1-0-2 and 1-0-3.
And when I think they say ja-ja, but are not really listening to what I say, they get a nice light that runs on alkalines.

Now what can happen if the coating prevents the light to get rid of the build up heat? You will fry the LED or the driver.
You will not burn yourself, because the heat can’t come out (presumably). And you can always use protected batteries.

PS I always think long and hard before I say something very stupid.

I will think about what I will do next. But please don’t get your hopes up.

There were no underestimations, I am aware that the powder coat insulates the light slightly, that is the whole reason I said do not run over 2/3A (I personally run mine at 3A) but as pointed out that some people won’t be sensible so I dropped the recommendation to below 1A

The discharge temperature for most li-ion batteries is –20C to 60C (–4F to 140F)

As long as the battery doesn’t get hotter than 60C/140F you will have no problems

Take a look at HKJ’s battery tests. A Sony VTC5 discharging at 20A hits 45C/113F

Obviously take into account that the battery is contained in the light so the temperature will be higher, but also take into account that you won’t be running the light at 20A

I thought BLF was about pushing the limits and that is why we run leds rated at 3A at double that. And that’s why I make lights that push the max possible.

But this is also the reason I don’t build high power lights for people unless they specifically request something and know what they are doing.

Running a XML2 at 6A in a S2+ is impressive, but gets very hot and again, can be a safety issue. The LED overheating isn’t really a safety issue, it will just burn out, however a li-ion battery overheating is a safety issue. This will happen if the light is powder coated or not.
There’s just as much chance of a XML2 running at 6A blowing up, than a XML2 running at 3A in a powder coated light.

I could easily leave bare aluminium near the pill so there is an ‘open heatsink’ but it would ruin the look of the light.

Also, take a look at some of the other popular light coatings (cera/dura etc.) I think you’ll find that It is just as bad as it contains a lot of polymer. Powder coat just doesn’t have the ceramic element.

I was going to do a custom run for BLF that I would have to put a lot of time and money into (£30 for powder, 20 hosts £160, consumables needed for the process £20) the only reason I could do them at this price was doing 20 at once limiting the time for setup etc.

To the ‘safety patrol’ you’ve not ruined anything for me, I wasn’t making a profit, and I’ll still make myself a flourescent light, you’ve just ruined it for everyone else who wanted something a bit different.