Heating to fix broken connections

Borad

Enlightened
Joined
May 27, 2011
Messages
227
When I turn on old, one mode Fenix E05 it becomes dim, then I have to slightly loosen it for full brightness (it shouldn't work like that). Maybe pressure on the board caused it to bend and break a connection. I could try to add some solder to the copper that touches the battery but I'd like to take out the board and look in the back and maybe use a heat gun to melt everything and hope that fixes any broken connections. Could the head of the light (shown in photo) be further unscrewed or is it glued together? I don't have a microwave oven (I heard nuking electronics sometimes fixes them).

2m3oivs.jpg
 

Str8stroke

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Nov 27, 2013
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I hope you tired to clean the threads before you began all that? Sometimes lights can act really goofy and just need the threads cleaned well. Also try a little bit of dielectric grease on the threads. This can smooth things out and helps keep moisture at bay.
 

Borad

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Joined
May 27, 2011
Messages
227
I cleaned all the contacts and the threads feel OK when I tightened it but it was worse than ever.

I tried a heat gun to loosen the thread locking but I gave up with that and just filed down a nut and jammed it in the tube so I could clamp it tightly with pliers without crushing it too much, then I used another pair of pliers for the end with the lens and hoped I wouldn't crack it, and I was able to unscrew it. I got this far:

flashlight_emitter.jpg


The board(s) don't just slip out so I don't know where I'll go from here. I was hoping I'd get access to a board with copper traces that I may be able to melt together.
 

archimedes

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Nov 12, 2010
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CONUS, top left
Although anything is possible, usually ...

"broken connection" (solder fail, broken wire, detached component, etc) = "no light"

"increased resistance" (dirty threads, corroded contact surfaces, etc) = "dim light"

"intermittent connection" (switch or driver not fully seated, spring problem, contact wear, battery crushed or too short, etc) = "flickering light"
 

Borad

Enlightened
Joined
May 27, 2011
Messages
227
It worked! This is what it was like before I fixed it:

flashlight-problem-animated.gif


Then I held a heat gun to the emitter end and the battery end for several seconds each and it improved but the red and black wire insulation didn't melt at all, so I tried the heat again, for a longer period, and it worked! It seems those tiny wires have more heat resistant insulation than typical electronics.
 

Borad

Enlightened
Joined
May 27, 2011
Messages
227
It was like new for a while but tonight it flickered and when I turned it off and on it was dead.
 

snakebite

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Mar 17, 2001
Messages
2,721
Location
dayton oh
looks like there is a snap ring in there.remove it and see if you can get it apart.
once the boards are out add flux and reflow the driver and led.it sounds more like a flex failure.i have seen that on parts with a wider span like inductors and current sense resistors.
scrape/sand the shelf the driver sits on.might have dissimilar metal corrosion there and on the ground trace on the driver.
and never microwave electronics unless the intent is to destroy them.
When I turn on old, one mode Fenix E05 it becomes dim, then I have to slightly loosen it for full brightness (it shouldn't work like that). Maybe pressure on the board caused it to bend and break a connection. I could try to add some solder to the copper that touches the battery but I'd like to take out the board and look in the back and maybe use a heat gun to melt everything and hope that fixes any broken connections. Could the head of the light (shown in photo) be further unscrewed or is it glued together? I don't have a microwave oven (I heard nuking electronics sometimes fixes them).

2m3oivs.jpg
 
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