[Group Buy Interest Poll] Tiny EDC keychain light done right - BLF/Sofirn-style!

Other Types of Lights Keychain / Pocket Flashlights
91

A little announcement: it will be aluminum to keep costs as low as possible, but stainless steel and titanium versions are possibilities. :slight_smile:

sb56637 I hope that good knurling will make it sufficiently easy to use one-handed, including for lefties.

pooptoast The RovyVon A series are quite nice, but their biggest downside is the high cost. How did yours die?!

Noir Awesome response! Great points, and I especially appreciate the great detailed reasoning in line with the goals of this light. I agree with many of the points. Some probably won’t make it though, such as USB-C, LVP, and regulated output for a light in at the target price point.

For the wear concern with aluminum, what do you think of hard anodization (Type III) without dye? There would be no paint to scrape off, so it would not look as ugly if scratched. Plus the “natural” look might be appealing to some. Personally, I think this could strike a good balance between wear resistance and low cost.

What is the reason for visually linear brightness spacing? Especially with only 2-3 levels, would it not be better to select them for use-cases? Actually, I have a proposal on this subject which I may share later. :wink:

jon_slider Thanks for dropping that link to the historical small lights! A modernized Drake with built-in charging would be a good target here.

As for QTC, that’s really cool! Though I do have concerns about cost, long-term reliability, and usability. An video I found demonstrating its use showed it was rather finicky and sensitive especially on a small light. I think that would get frustrating, particularly on a tiny light.

Scallywag Personally, I agree with you on color temperature and tint being more important than high CRI on a keychain light. On the other hand, there seems to be a fair bit of interest for CRI, plus it would be a distinguishing selling point since not many other keychain lights have it. The eventual selection is likely to be a common use emitter like the the SST-20 4000K, which seems to strike a pretty good balance for what various people want.

Muto, Th558: Yes, perhaps a different version would be good for those who want a bigger battery, but aren’t there already such options? Although the 10280 is intriguing, I’m not sure it distinguishes itself enough from either the 10180 or AAA.

shirnask The goal is as tiny as possible with the features mentioned. :slight_smile:

flightless Yes, reliability is key! That has been a big concern of mine while researching keychain lights.

Oli I presume it will have O-rings for water resistance as most of them do. A glow in the dark O-ring under the bezel would be a nice bonus. As much as some don’t like twisties, it’s hard to find an alternative that is as simple and reliable. As for the Acebeam M50, its custom 10150 battery is a deal killer for me. Just why…

92

Interested!

93

Interested in 1 thanks!

Good ano might be an issue, anything keychain related usually gets a thrashing after a few weeks.

Cheers!

94

Quantity I would buy: 5 (if side switch and price below $10 and 2x10440 or 2xAAA) :smiley:

Suggestions
Switch: Side switch
Emitter: CRI SST-20 4000K (like the C01S)
Reflector/Optics: TIR lens (like the C01S)
Charging: built-in micro USB (plus cable)
Battery: As big as possible (2x10440?) but sealed to make the light as tiny as possible. Make it possible to replace the battery with some tools
Modes: Moonlight-Low-High-(Turbo?)
Brightness: Moonlight = 1LM, Low = 15LM, High = 100LM, (Turbo = 360LM ?)
Price: below $10 :smiley:
Other:
I know that the goal is to limit it to roughly 40mm x 14mm and ~12g, but… maybe it would be better to make it a little bigger (2x10440?) and put there a nice driver to be able to claim it the longest running double AAA on the market?

Acebeam UC15 Keylight (uses 2 x 10440 or 2 x AAA)

I would suggest to put second led like Nitecore did in their Tip2

Other shapes for inspiration (size could be corrected to contain 2x10440):
Nitecore TINI or Mateminco CSF02 “AKA” Astrolux K1

MecArmy SGN5 or YLP Scorpion X8

or Frelux Synergy 1

95

phouton - The light won’t take a charge anymore. When I charge it the blue light comes on but the red low battery indicator never shuts off (low battery indicator comes on at 2.6 volts). To Rovyvon’s credit, I contacted them and they are sending a replacement under warranty.

96

that is a 2x aaa light with Lumintop Tool/IYP electronics… Way too big to be on a keychain

meanwhile you can get a stainless 10180 light for under $20

speaking of deals, some of us are buying Copper Tools for $10

97

Side switch allows for accidental activation.

2 batteries makes it too big for a keychain light.

15LM on low is too low for any practical use.

98

With the specs on the second post, I’d buy one or two.

High cri 4000K sounds good to me. I’ve got two other lights with this emitter and I like them quite a lot.

I haven’t read the entire thread but for the charging port, I’d prefer it to be under the threads of the head instead of covered by a rubber gasket.

99

Heres an eventual contribution to this thread!
Disclaimer: a) I don’t use this light as keychain; b) I use a Rovyvon light as keychain and as a neck light and…they will be hard to beat for me! Still, I am open to this thread’s development!

This is the DQG Slim Ti in it short format. It takes a 14250 (half size of an AA/14500 cell) and 1 or 2 AA / 1x 14500 batteries when using extension tube(s), has 3 modes, no memory, XP-G2 on the rosy side and a TIR (originally was narrow beam, I modded and put a pebbled TIR).

Compact, bigger duration than an 10880, just probably larger.

Driver and LED come together, switch is replaceable, doesn’t have integrated charging, batteries are replaceable too!

Review Thread: “REVIEW”: DQG Slim Ti (1/2 AA and other batteries) ***[DISCOUNT CODE ADDED - 05/22/2018]***

Later I can compare it with some other keychain lights in terms of size and output (using an AA cell, as I don’t have any 14250, yet)!
I can tell that it is smaller in length than a RovyVon Aurora A8U…

100

Very interested and like Noir’s specs on post 68.

101

Rovyvon lights are larger than the smallest AAA lights out there while having half of battery capacity.
(And they are dimmer than the brightst 10440 lights out there).
Though to be fair - they are smaller than the smallest rechargable 10440 lights out there.

102

Some photos to illustrate what I mentioned above, about the DQG Slim Ti!

So, what about the possibility to create a light that can be like this but slimmer (10180 and/ or 10440)?

at Agro

Yes, the RovyVon Auroras are larger than some of the smaller AAA lights (maybe the Olight is the smallest one), they are dimmer than the most powerful 10440s (the upgraded Folomov is the best example), but they also offer in-built recharching and, depending on the model, they offer quite nice “alternative lights”, such as UV, red, blue or even side white light that most of the times is enough for daily tasks.

Don’t get me wrong, I am just saying that for me, this project has to stand out to make me use other lights than the RV!

I am keeping an eye on it, though, as it is interesting to see how it progresses and where it will “end” (starting the lights’ production, I hope!) :wink:

So, thanks for your contributes on this :wink:

103

Interested in 1:)

104

I agree, clear anodization (or perhaps no anodization) would be a good choice for an Al variant.

With visually linear mode spacing the perceived brightness change (or step) between low and medium is the same as the step from medium to high. In other words: the medium mode is perceived to be right in the middle between low and high. It's simply pleasing to the eye :cool: . On many lights the medium mode (or the middle modes on lights with more than 3 levels) is brighter than it would be with visually linear mode spacing resulting not only in a small perceived difference between medium and high, but also a much reduced runtime for the medium mode. On lights that don't have perfectly flat regulation it gets even worse with depletion of the battery, to the point were you are asking yourself if it is necessary to have two different modes that are barely distinguishable from one another.

Simply put visually linear mode spacing is a sort of "ideal" (that's why I like it :) ). While it is of course not necessary to stick to this ideal, I personally think it is still a good idea to make sure you don't deviate too far from it in cases where you need or want to select brightness levels base on other considerations (such use case or specific runtimes). For example: on a 3 mode light with a low of 1,5 lm and a high of 150 lm the ideal (i.e. visually linear) medium would be at 15 lm (constant factor of 10). If you want a higher medium (most people are used to this since the majority of commercial lights have higher than visually linear medium/middle modes) 1,5 | 25 | 150 lm would still be just about acceptable in my view (factor 16,67 between low and medium and factor 6 between medium and high). A spacing of 1,5 | 50 | 150 lm on the other hand would be too far from the ideal in my view, huge gap between low and medium (factor 33,33) and very small gap between medium an high (factor 3).

In case anyone is interested in more details, have a look at "Stevens's power law" and the chapter "The Human Visual System" in the "LED Flashlight White Paper" by Henry Schneiker (founder of HDS Systems).

Regarding QTC:

Many Years ago I bought a Veleno Designs Quantum D2 (a small 10180 light with QTC brightness control). On paper it sounded great, but in practical use it left me a bit underwhelmed (I sold it after only a short period of time). The brightness control was finicky, when twisting the head the brightness jumped around and it was difficult to get to a specific brightness. The main reason for this undesirable behavior is the play in the threads, so ideally you would want very high precision threads with next to no play on such a light (which is of course not possible on a budget light since it would drive up cost massively), not to mention other concerns like the durability, availability of replacement QTC and the force/tightness needed for full brightness. In short I would vote against QTC.

105

I like the side switch in the above flashlight but I would really prefer switch to be a little bigger:

something like the one here: UltraTac K18 Mini

And I still think that flashlight that would works on both 10440 and NiMH AAA would be a winner:
something like the one here: UltraTac K18 or Jetbeam E01R

Quantity I would buy: 3 (if side switch and price below $10 and runs on 10440 or NiMH AAA)

106

I have absolutely zero interest in keychain lights. Just sayin’…

107

I would also vote against QTC.

As far as the Hobi+, it’s available with an extension tube for 10440 support. It won’t change the brightness but it will get you runtime if that’s your thing.

As far as this light, I’ve decided I’m not interested in an aluminum version. However, I hope things go well, and that a Ti version comes along…

I worry about the tint on that SST20… I dream of 219B but I fear it can’t be reliably sourced.

108

rost333 I think you’re looking for a very different light. Nice pictures though.

pooptoast Strange. I wonder if there are reliability concerns with USB charging circuits. At least you’re getting a replacement.

PBWilson It hasn’t been discussed, but I’d expect the charging port to end up under the threads. Certainly that is my preference too.

MascaratumB Thanks for the info and review of the DQG slim Ti! In general the addition of USB charging adds length, so that’s something we need to keep in mind since it is a majorly desirable feature.

I have some concerns with the DQG: 1) that diameter (a bigger problem than moderate length) starts to get uncomfortably large for a pocketable light, 2) switch reliability as mentioned in your thread is worrisome, 3) the tube extension and battery options suggest a different usage target than for keychains.

As pointed out by Agro, the size approaches AAA lights (especially if you add USB charging). I have a hard time justifying these in-between sizes since to me they seem like the worst of both worlds: too big to compete in size with 10180 keychain lights, and too little capacity compared to AAA. Maybe there is some niche for them… I just don’t see it yet.

Noir I understand that visually linear levels look more natural, but wouldn’t it be more important to select functionally useful levels? Do you find 10-15 lumens to be enough for most keychain light use? Nice links btw.

beggindog It takes all kinds to make a world. :slight_smile:

Scallywag Stainless steel and titanium versions are possible at a higher price . :wink: [Group Buy Interest Poll] Tiny EDC keychain light done right - BLF/Sofirn-style! - #91 by phouton

109

This is actually a great feature. Tubes are cheap, heads are expensive. With a shorty tube you have a light that’s comfortable to carry and still has enough capacity for many short bursts. Extend it - you suddenly have way more capacity at the expense of extra bulk.

110

Great idea. I’d probably shoot for the smallest tube for a keychain light but I could see a longer option and longer runtimes a plus for some folks I know.