The There Are No Stupid Questions Thread

Hmm. I’m not sure which of these two interpretations you meant:

What battery model is best? Depends on the kind and size of battery.

What kind and size of battery is best? Depends on the application. Button cell batteries are almost always bad though. :D ;)

The big ones, usually.

Those are the ones I like.

If I were to choose a failproof thrower flashlight into urban exploration of a miles long pitch black underground tunnel system, is the Thrunite Catapault v6 or the Manker U22 more reliable? Is my Sofirn SP31T as good as either, or is a Zebralight SC600 MKIV more failproof than all 3? Or is the Armytek Barracuda Pro the most failproof relatively compact thrower? Can I depend on my SP31T to be failproof or do I need to spend money to buy something else?

Its depend… i will say sony vtc5a… then samsung 30q, sanyo ncr18650ga.

I will say thrunite catapault v6 is more reliable…( still waiting for my v6). i have thrunite tn36ut, tn30, tc20, tn42, and tn40s. thrunite driver and spring are bulletproof… they never failed on me.

98% of time, flashlights need button top…

Re: failure-proof flashlights.

There’s no such thing. Always carry a backup.

You can certainly get extremely reliable flashlights, but nothing is ever perfect.

The best flashlight in the world won’t do you any good if you drop it and the cell fails. It happens; there have been a few “torture tests” where the light survived, but the cell didn’t. Always carry spare cells.

It is a very good idea to choose primary and backup lights that can use the same type of cell. That way, you won’t get into a situation where you have a dead light with charged cells, but you’ve used up the cells that fit the working light and you can’t swap them over.

Thanks so much.

These batteries are expensive, and flashlights that use them tend to be not much smaller than AAA lights, which offer much more brightness and runtime, IMHO. :)

We seem to be getting confused between “cell with button top” and “button cell”. They’re two different things.

“Cell with button top” on the right, “cell with flat top” on the left:

[Image courtesy of wheniwake on Planet of the Vapes ]

“Button cells”, also known as “coin cells”:

[Image courtesy of Wikipedia ]

I think you have that reversed. I have only one 18650/26650 light that requires button-tops (BLF Q8). All others either require flat tops (such as Zebralights), or work fine with flat tops (anything with springs or posts at the positive end).

Yes, I meant those coin cells. ;)


I don’t have the tools to test this. If I hook up a Nichia 219c 4000K directly (no driver) to a fully charged 30Q just to test and compare tints, approximately how many mA is it pulling?

The 219C has a low forward voltage (Vf), so unless the led has very good heatsinking, the answer will be too many, enough to damage it.

I agree with ggf31416, you’d definitely be risking damage to the LED.

You could just solder a 7135 or two to a piece of stripboard, though - that would be enough of a “driver” to keep things under control.

Question about Nichia. On Reddit I often read about this. Why Nichia so cool?

They’re one of the few LED mfrs that make high-CRI LEDs.

If you notice how if you’d use a CW (cool-white, ie, bluish-white) LED when looking at, say, a woodgrain cabinet, it’ll look a dull dingy grayish-brown color. With even low-CRI warm-white, reds and browns will “pop” and be much more vibrant.

High-CRI means that whatever color-temperature you’d have — cool, warm, or neutral — you’d be able to see truer colors as if under natural daylight, that blues will look blue, reds will look red, etc. Differences can be very subtle, and you’ll hear things like “R9 value” and such, which is a shade of red that lots of LEDs have problems handling.

Nichias were (probably?) the first to offer high-CRI LEDs, ’though now others are starting.

Thank you!
And what about Cree?
Why the majority of companies use Cree, not Nichia?
That’s too expensive?