Armed Polite Society

Main Forums => The Roundtable => Topic started by: Hawkmoon on June 13, 2019, 01:56:21 AM

Title: LED flashlight died
Post by: Hawkmoon on June 13, 2019, 01:56:21 AM
I guess.

Not an expensive, "tactical" light like a Surefire or anything. This one had one mode -- ON. (Or off -- okay, two modes.) It used three AAA batteries in one of those "rotary magazine" type battery holders. Bought several years ago as a 2-pack from The Sportsmans Guide. 100 lumens.

I've been very happy with these lights. This one I keep hanging from a nail in my basement work area for when the lights go off (which they do around here with increasing frequency.) Wednesday evening I needed to inspect a couple of parts to see where the interference was that was causing a rub. Grabbed the light, and all I got was a dim glow. New batteries didn't make any difference.

Do LEDs fail by going dim? I thought they either worked, or didn't work.
Title: Re: LED flashlight died
Post by: Perd Hapley on June 13, 2019, 02:21:36 AM
The diodes themselves will eventually go dim, but I don't know if it's the LEDs that are the problem. It's usually the driver that causes issues. Either way, toss it. Buy a new one. "Several years" is probably about all the life you can expect from lights like that.

The life of an LED lamp or fixture is measured by estimating how many hours it can burn before it dims to 70% of the initial lumen output. It's known as "L70." Some manufacturers will use L80, instead.
Title: Re: LED flashlight died
Post by: Hawkmoon on June 13, 2019, 04:36:34 AM
That's what I was afraid of. It wasn't an expensive light, but I liked it ... and it's no longer available (at least, not that I can find). I guess I'll have to start looking around for a replacement.

Thanks.
Title: Re: LED flashlight died
Post by: Boomhauer on June 13, 2019, 05:35:52 AM
Ones like that aren’t made to last long
Title: Re: LED flashlight died
Post by: 230RN on June 13, 2019, 06:12:42 AM
At that age, it's probably something mechanical in the <ahem> mechanical switch.

But rotate or spin the batteries in the "cartridge" to re-establish good contact between the six (6, count 'em) contact surfaces in the battery pack.

Everybody laughs at me for suggesting it, but the aluminum-to-aluminum contact in the body to cap mating surfaces sometimes needs a little twist to break through any oxide layers between them.  Don't forget that aluminum oxidizes very very very readily, and guess what is so good an insulator that they use it for insulators?

Aluminum oxide, that's what.  AKA "alumina."

I don't know how many times a simple twist and twist-back of the endcap has restored the brightness (i.e., the contact) in those little freebie lights from Harbor Freight.*

Terry holds up hands to quell the laughter.

But  yeah, at this late date, it's probably the switch.

Terry.... who never completely trusted aluminum connections anyway, 230RN

*I regularly pick up a couple of these almost every time I'm in Harbor Freight.  I've got them everywhere you look in the house.  Kind of a flashlight junkie for junkie flashlights.
Title: Re: LED flashlight died
Post by: Doggy Daddy on June 13, 2019, 01:05:43 PM
These are my go-to cheap LED lights.  Been buying them for quite a few years, very few failures.  I have one clipped behind the hinge on every door in the house, and spread about in drawers everywhere. 

(https://images-na.ssl-images-amazon.com/images/I/71wPMMc-LRL._SL1100_.jpg)


https://smile.amazon.com/MIKAFEN-Flashlights-Flashlight-Adjustable-Zoomable/dp/B0183JMQ9C/ref=sr_1_6?keywords=led+flashlight&qid=1560445294&s=gateway&sr=8-6 (https://smile.amazon.com/MIKAFEN-Flashlights-Flashlight-Adjustable-Zoomable/dp/B0183JMQ9C/ref=sr_1_6?keywords=led+flashlight&qid=1560445294&s=gateway&sr=8-6)
Title: Re: LED flashlight died
Post by: MillCreek on June 13, 2019, 01:12:24 PM
^^^I buy those exact flashlights from Amazon as well.  I suspect they are all made by the same few companies, since they are sold under numerous labels and all look to be identical.  I just look for the cheapest price.
Title: Re: LED flashlight died
Post by: dogmush on June 13, 2019, 01:18:35 PM
China freight has these in 2.99 2 packs.  Lots of times they are the "free gift" coupons. With decent batteries they last pretty well.

https://www.harborfreight.com/2-piece-3-12-in-led-mini-flashlight-63600.html
Title: Re: LED flashlight died
Post by: Brad Johnson on June 13, 2019, 02:35:04 PM
IF they glow, but only dimly, and you've put in what you are absolutely certain are fresh batteries, then it's probably one or more of the internal contacts. Cheapo flashlights usually don't drive the LEDs hard enough to degrade them appreciably over the very few actual working hours th've been used.

Brad
Title: Re: LED flashlight died
Post by: Hawkmoon on June 13, 2019, 05:00:43 PM
These are my go-to cheap LED lights.  Been buying them for quite a few years, very few failures.  I have one clipped behind the hinge on every door in the house, and spread about in drawers everywhere. 

(https://images-na.ssl-images-amazon.com/images/I/71wPMMc-LRL._SL1100_.jpg)


https://smile.amazon.com/MIKAFEN-Flashlights-Flashlight-Adjustable-Zoomable/dp/B0183JMQ9C/ref=sr_1_6?keywords=led+flashlight&qid=1560445294&s=gateway&sr=8-6 (https://smile.amazon.com/MIKAFEN-Flashlights-Flashlight-Adjustable-Zoomable/dp/B0183JMQ9C/ref=sr_1_6?keywords=led+flashlight&qid=1560445294&s=gateway&sr=8-6)

I have six of those stashed in various places. One lives in the cargo pocket of my cargo pants at all times. They're cheap, but handy.

But it wasn't one of those that failed.
Title: Re: LED flashlight died
Post by: Doggy Daddy on June 13, 2019, 06:46:36 PM
I have six of those stashed in various places. One lives in the cargo pocket of my cargo pants at all times. They're cheap, but handy.

But it wasn't one of those that failed.

So, what have we learned from this?   =D
Title: Re: LED flashlight died
Post by: 230RN on June 13, 2019, 07:45:58 PM
That just about the same failure modes exist in all these types of flashlights disunirregardles of cost or manufacurer. There are at least ten or twelve contact points in the whole circuit.  And you can count the switch and other circuitry as at least two contact points, even if the switch just plain poops out mechanically, as in no clicky-click.

And unstated but obvious, the nice thing about having duplicates is it makes diagnosis easier by parts-switching.

IF they glow, but only dimly, and you've put in what you are absolutely certain are fresh batteries, then it's probably one or more of the internal contacts. Cheapo flashlights usually don't drive the LEDs hard enough to degrade them appreciably over the very few actual working hours they've been used.

Brad

Yeah, basically what I said in Reply #4.

Terry, 230RN
Title: Re: LED flashlight died
Post by: Brad Johnson on June 13, 2019, 10:02:53 PM
Yeah. What Terry said.

Brad
Title: Re: LED flashlight died
Post by: zxcvbob on June 13, 2019, 10:43:06 PM
This is by far my favorite flashlight (I have way too many cheap little flashlights, and a few expensive ones) https://www.amazon.com/Smith-Wesson-Flashlight-Waterproof-Mountable/dp/B00BU9DSHW (https://www.amazon.com/Smith-Wesson-Flashlight-Waterproof-Mountable/dp/B00BU9DSHW). 

I thought it quit after rolling off a table and falling about 18 inches to the floor a few months ago, and I was pretty pissed about it, but what really happened was the flat top battery I in it with a little homemade adapter (it only works with button top batteries) had dented on top and wasn't making contact.  If I had been using the right batteries it wouldn't be a problem.  I was even able to repair the dented battery, but now I know to use the right batteries when I really need to rely on the flashlight. (like these: https://www.illumn.com/18650-samsung-3000mah-inr18650-30q-high-discharge-button-top.html)
Title: Re: LED flashlight died
Post by: 230RN on June 14, 2019, 05:21:25 PM
This is by far my favorite flashlight (I have way too many cheap little flashlights, and a few expensive ones) https://www.amazon.com/Smith-Wesson-Flashlight-Waterproof-Mountable/dp/B00BU9DSHW (https://www.amazon.com/Smith-Wesson-Flashlight-Waterproof-Mountable/dp/B00BU9DSHW).  

I thought it quit after rolling off a table and falling about 18 inches to the floor a few months ago, and I was pretty pissed about it, but what really happened was the flat top battery I in it with a little homemade adapter (it only works with button top batteries) had dented on top and wasn't making contact.  If I had been using the right batteries it wouldn't be a problem.  I was even able to repair the dented battery, but now I know to use the right batteries when I really need to rely on the flashlight. (like these: https://www.illumn.com/18650-samsung-3000mah-inr18650-30q-high-discharge-button-top.html)

So, an internal contact problem per Reply #11, exacerbated by your jinning up an adapter for the cell.

Terry, 230RN
Title: Re: LED flashlight died
Post by: zxcvbob on June 14, 2019, 07:44:49 PM
So, an internal contact problem per Reply #11, exacerbated by your jinning up an adapter for the cell.

Terry, 230RN

Yup.
Title: Re: LED flashlight died
Post by: Doggy Daddy on June 15, 2019, 12:59:59 AM
So, an internal contact problem per Reply #11, exacerbated by your jinning up an adapter for the cell.

Terry, 230RN

That's the way I read it too.