BLF A6 FET+7135 Light Troubleshooting and Mod thread

I’m sorry I can’t speak for banggood. But maybe Neal is keeping an eye on this thread.

Am I the only one who likes the clip? It clips.

I ALWAYS solder the bypass wire inside the spring. The spring is steel, usually, and the solder is likely to let go at some point due to the compressions of the spring when loading cells. So, if the wire is on the outside it is quite likely to cause a short at some point. Inside, it’s contained by the spring itself and can’t reach ground.

Edit: And also, if you must put a ring inside for proper tube to retaining ring contact, remove the retaining ring and put this spacer between the driver and the retaining ring so you don’t have loose parts. Once you re-install the retaining ring it will be spaced upward to meet the tube but everything will be snug and contained. :wink:

Before going to all this trouble, double check that the tube is inserted properly. Even if the clip is on the wrong end, I guess it’s possible the tube could be machined backwards, but it’s normal for the clip to install on the tail end of the tube. It only works one way, it’s not reversible.

Good point DB. I’m having a tough time with flowing at the base of the spring. I think I need a better iron and some helping hands.

Just remember, heating up the pad at the base of the spring is also heating up the switch. Pretty much as easy to kill the switch here as soldering directly to the switch.

Try removing the spring from the board, soldering the wire on in the middle, then run the wire up through the spring and solder the spring back on around the edges. Cut the wire a little long, coil it inside the spring slightly so it’s got easy room to compress, then solder the top end of the wire to the top of the spring. I like folding the wire over the very end of the spring then soldering it. Even if the solder lets go of the spring the wire will stay in place.

Edit: A through-pcb bypass for high amps…

Do I hear a lathe in the background? :-)

Btw, I stand by my method doing the spring bypass on the outside, it is a bit theoretical in my opinion that the solder joint at the base of the spring would break, it is stiff one piece with the base under the spring.

Everyone has their own style :-)

Style notwithstanding, what happens if the top lets go and the wire… still connected at the pad… touches the side of the pill? Direct short, of course. Once you’ve had this happen, you develop more of a safety conscience than a style. :wink:

Also, keep in mind, we are advising many people around the world here with unknown soldering skills. Err on the side of safety.

My soldering skills are known. They are known to be somewhere between bad and nonexistent.

So does anyone make a short little quick-blow fuse with wire leads, that could serve as a spring bypass?

Seems like a thoughtful redesign of the whole switch notion could pay off considerably if there’s a way to separate the conductor from the spring in a way that would negate these low-likelihood, high-boom direct short possibilities.

Perhaps you could make your own by cracking open a glass automotive fuse, or by melting the plastic on a plug-in type with solvent?

Phil

DB I’ve add your video to the op. Along with some explanation as to why it’s safer. I hope that helps a lot of people! Thanks!

Let’s say “potentially” safer, we want people to think on the side of safety while they’re modifying these lights, right? I mean, reckless abandon is well and good when with a consenting adult but sometimes thoughtful care and consideration are appropro…

Yes there will always be tree burning. And triples you can weld with. Right? :wink:

Wait til you build your first small triple, it’s so exhilarating, scary, and just outright fun you’ll wonder what took you so long.
The first time I saw 12A in a smallish light, man, what a trip! Then I saw 16Amps, 17Amps, holy cow, I was afraid to turn it on! And now I have a quad Titanium X6 pulling 21.3A from a single cell, yeah, it’s just freakish and fun and mindblowing and dangerous and and and…

You’ll see! You’ve got the bug! :stuck_out_tongue:

If you want a fuse, it’s pretty simple to do. Just don’t bypass the spring. The spring will act as a fuse.

I know this because I’ve destroyed springs that way. It actually works pretty well, and prevented anything else from getting damaged.

After a night's sleep I understand the safety concern of an outside spring bypass a bit better: I know I make solid solder joints but not everyone will make a good job of it, and you don't want to have it come loose. I think what TK says is a pretty good point: the driver spring of the BLF-A6 is not so long, so the gain of a bypass is a bit less so just leave it out. You can still do the tail spring bypass any way you want it because when it shorts there it is not a direct battery short but the light just switches on (in my case in moonlight :-) ), much less of an issue for something that will not often happen anyway.

Last night I did a spring bypass on both springs. Testing with a 25R freshly charged with 4.19v yielded 6.7a on my Fluke clamp meter…wow! Is anyone else seeing that many amps? Hopefully that poor little XPL can live at that power level.
The driver on this light is awesome;
Great UI
Nice moonlight
Lots of top-end output
Many thanks to everyone who worked on this project!

wow, that is more than anyone got yet, you must have had a very low voltage XP-L by chance. I have had XP-L leds that went to over 9A en ones that blew at 7A, so you may just be lucky with this one :-)

Good work Scot! You are now solidly addicted. :stuck_out_tongue:

I have one that’s doing 6.2A on a Samsung 30Q, an HI variant actually, but most don’t go that high. Like Jos says, it’s the luck of the draw.

Hey Dale, since switching to your method of using my clamp meter to Measure amp draw, my readings have gone up, a lot. Here’s another point worth noting, I took the battery directly out of the BLF light after testing and placed it in the A6 I won in your giveaway, and amp draw dropped to around 5.4. Edit 6.1a