Thorfire TK4A go boom... (fixed, resolved!)

Well, more like a dull thud. Was reaching for it, it slipped, fell over a whopping 2 inches or so onto my laptop’s keyboard. Forget about shooting it out of a cannon, running it over with a hummvee, or deep-frying it… it got killed by a Dell.

Checked the fairly new alkaleaks, good. Spring-thingy in the tailcap spins fine, disassembled the head, everything looks fairly solid there. The “pill” comes most of the way out and is held in by the 2 wires going to the mcpcb.

No shakes, rattles, nothing loose bonking around in there… so wotnahell killed it? It practically went from tailstanding to sideways on a keyboard — a keyboard! —, and croked.

Anyone know what might be the most likely failure mode? Weighty toroid coil pull loose? Switch pcb crack somewhere so that it can’t be turned on? Anything else on the driver board that could crack or come off? I’d really rather not bust something that ain’t already busted. And it isn’t like I can just drop in a new 105C or anything…

I figure once I start unsoldering things at random, it’ll be dead for good. :confounded:

I’m seriously doublenonplussed.




edit: Fixed it!

Thanks to BLightSam for the fix! See below. You ain’t gonna believe it. :smiley:

Does the switch still light up?

I’ve had head wobble ruin LEDs. Are you able to apply power to the LED before disassembling everything?

Or just put the right or similar voltage with a variable psu to the pcb even before everything else

No light on the switch, didn’t try the LED itself, just seems dead as if the cells aren’t making contact somewhere. Maybe the driver lost its ground to the case (spring), who knows.

Will try poking around some more when I get home… tnx!

retaining ring got loose? My Sofirn SF14 suffers from loose retaining ring sindrome

Hmm, can’t quite see any retaining ring. I see a screw through the driver board on the side opposite the switch, but that’s it. Was hoping there’d be the battery tube separate, vs battery-tube plus the sub-head holding the driver.

Bah, looks like I’m gonna hafta desolder the LED anyway. Would be a good opp to swap in a 5D on Cu when I have that open, but not if it ain’t gonna work afterwards…

Not the same circumstance, but it can happen to anyone’s light:

Interesting thread about the EA11… different setup, but was thinking of trying a direct connection to the springs.

I have numerous ThorFire flashlights and have not had a problem with any of them other than the TK4A. It was very slow changing modes and after less than an hour of use it stopped working. No drop or anything it just stopped working. I returned it to Amazon for a refund and didn’t bother buying a replacement.

I don’t mind the slow mode-changes, but I’m pretty disappointed that it could just up and die like that. It’s got to be something simple and stoopit, and all I did so far was a visual inspection. Don’t want to unsolder the mcpcb yet ’til I hear from TF. The return-deadline is the end of the month, so I want to see what they’d say, first.

I’d still very much rather have a replacement than a refund, as it’s quite a nice light when it works. :smiley:

Hell, if it’s something I can repair, eg, if I could get a driver board to throw in there just for s&g and try it, I’d be willing to.

Maybe I should drop the other one I got onto a laptop and see if that one breaks, too. :laughing:

You would expect a more robust product for a light that costs north of $40 without batteries. The Thorfire website claims a “20 year lifetime” so maybe you can ask for a warranty replacement 404 It is no longer available on Amazon or eBay but the same light is sold by ThruNite as the TN4A light for only $56 https://www.ebay.com/itm/ThruNite-TN4A-NW-1150Lumen-XP-L-V6-LED-Flashlight-powered-by-4-AA-batteries/252223809230?epid=7011379869&hash=item3ab9b5e6ce:g:l0QAAOSwHPlWey6~. Obviously both companies buy them from the same manufacturer but with different brand names on the barrel.

Actually there is very little in common between the ThorFire TK4A and the ThruNite TN4A aside from similar names. Completely different interfaces, and bodies. For instance, if I recall correctly the ThorFire has the batteries inserted directly into the body while the ThruNite has a separate battery carrier. I actually found the UI of the ThorFire to be much more intuitive than the ThruNite.

Wellp, I got mine for like 15bux each on sale. :smiley:

That’s why I’m not going to cry myself to sleep at night over it, but as I mentioned, I’d much rather get a replacement vs refund. I genuinely like the little critter.

Dunno the Thrunite, but the TK4A is clones with the Sofirn SF11. Chicken, egg, no idea which came first… :smiley:

Either way, it’s a nice light, great feel in the hand, solid, just looks beautiful and sleek, just the right amount of “bling” (notches, knurling, etc.) to give it some personality without being all in-yo-face.

I bought the beasties just to burn off an assload of unopened in-the-case AAs I unearthed (good God, like 100 at least) that’d otherwise just go to Alkaleak Heaven without doing anything useful. But I ended up liking them. A lot.

Dunno, I’m just kinda bummed that it could be killed by a Dell. Who’d a thunk it?

Well that sucks man. Mine hasn’t been used much at all but still works. I had mine apart when I first got it, but can not remember snything about the design or how it’s made inside other than the missing screw on the MCPCB that I replaced…

Oh, just went back over the TF thread and I also swapped out the reflector and went to XP-L HI. Did some work on mine but still cant remember how it’s made inside. :smiley:

poped mine open… and starting to remember… the LED board sits on a floating pill, need to desolder the wires, remove the floating pill to get driver out. Driver is screwed to the tube and comes out the reflector end. E-SW board is mounted vertically to the driver and perhaps the solder joints cracked on the fall.
Starting to recall more bout it… mine has periodic issues where the tail cap is removed and occasionally does not turn back on when it is replaced. Just try it again till it works. I have no idea why.

Yep, that all fits with what I’ve seen. Only saw 1 screw holding in the driver board, opposite the switch. I only wanted to do a visual first, see if anything obvious would clue me in. Eg, a toroid flapping around on 1 wire, loose piece of solder that may’ve cracked off, etc.

I’ll wait ’til I hear back from TF before I go hacking away at it. Don’t wanna void any warranty…

After reading about the Lightbringer’s Go Boom story, holding the flashlight body in the right hand the head was lightly, gently tapped against the left open palm. When switch was pressed, no light even the switch. Got weird operations when pressed long, short, double. Opened and check the battery - all 1.46v. Put them back in, now get red switch light to boot and would not turn on except light flash. Thought I ruined it. Put fresh batteries in normal operation returned.

Changed to the old batteries and got back the normal operation, to my great relief. Hope somebody get some theory on what the cause is when Go Boom.

Son… of… a… beeyotch.

That worked!

Brand new cells in, snug up everything, press button… nothing. Wellp, what’ve I got to lose? Started slapping it silly on my palm… north side, south side, east, west, repeatedly, then all of a sudden… let there be light!

I’m going through the cycles, it goes through all 4 just fine, turns off, turns back on, more cycles, doubleclick for strobe, back, on, off, etc. Seems to be back to its old “normal” self.

Now to go ice my palm…

Okay, put back the semi-old cells, still worked.

Ain’t gonna risk any cells leaking, so ditched the 1.3x and 1.4x cells and put the three 1.5x cells, with one 1.5x new one. Still works.

Thanks, dewd, that so fixed it! :laughing:

I’ll burn down the other cells in a 1-cell light…

Hmm, still not quite sure if I should be happy or disturbed by what happened. :o

Thats kinda what I have been experiencing too. But I thought it was tail cap related contact issues.
Also wonder if it is some LVP triggering from poor or lost battery contact. I am running NiMh 1.2V so that has crossed my mind too. Perhaps the slightly lower batt voltage shuts it off and it gets restored if very fresh batts are replaced.

Glad its alive again. Will stay tuned to see if anyone comes up with a definitive answer/solution.