BLF A6 FET+7135 Light Troubleshooting and Mod thread

See first post - “Some flashlight basics:” to locate the error (e.g. battery tube, tailcap switchboard, switch, retaining ring …).

Mine had a too short battery tube which couldn’t get contact with the “outer area” of the tailcap. Banggood sent me a new battery tube so i could remove the workaround.

Both the 20-24mm and the 20-25mm fit the A6:
https://www.fasttech.com/p/1347102
https://www.fasttech.com/p/1140010

I like using these wand-type diffusers when walking along side the road. It shines like a lantern, so it is very visible to oncoming traffic from hundreds of yards away.

P.S. I do not remove the head when adding the diffuser. Works just fine that way. Besides, with the BLF A6, I’m worried about decapitating the LED whenever I unscrew the head.

If you remove the head, what keeps the LED board in thermal contact with the body of the light?
I thought pressure from bezel-lens-reflector-spacer held it down.

Yep, tried that, but it was was as far as it could go, I took the tail cap portion apart and put some rubbing alcohol on all of the parts, but the problem still persists.

Edit, paper clip text did not work the first time, but it did work the second time, except when I shake the flashlight, the light turns on.

About diffusers… it can also work to put some DC-Fix or similar on the lens. But that will merely smooth out the beam, not make it shine in all directions.

I like it with a blended beam, but haven’t had a use for a full-360 diffuser wand yet.

Welcome retriever222!!!

Sorry that your light isn’t working right out of the box.

Shaking it to make it work is a sure sign something is loose. Make sure your springs aren’t bent and making good contact with the battery. If you have a way to remove the retaining ring you can place the paper clip between it and the switch board. There is also another ring in the head portion as well if you can check it too. I hope you can get it to work but if not there is no harm in contacting bang good. We will help as much as possible if you want to get the light going.

Power outage general room illumination is what I’m thinking of.

An extra o-ring under the button cap will shift the switch pcb and retainer closer to the battery tube. On mine the button is too sensitive so probably needs the rubber post to be shaved or shimmed.

A local member asked me to look at a non functional one and it seems the driver retainer bottoms out on the threads before contacting the board. Upon close examination the threads are not cut all the way to the relief cut. It can be fixed by soldering tabs either to the board or to the ring.

I ordered this holster from Fasttech. Very well made and fits perfectly. The side storage sleeve for a spare 18650 battery is too loose to be of much use, though.

Unfortunately, this item is currently out of stock. :ghost:

An update with pics on the fix of the driver retainer issue(retainer threads stop too soon). The best place to add a ground tab to the driver is at the location of the patch of ground vias located by the FET ground pins. Another is added opposite for simitry and to pick up the 7135. The solder mask has neen scraped away and the underlying copper tinned along with some .8 mm copper bits which then get soldered into place. Snip and sand these down until the driver fits back in and your gtg. All fixed Cf!

On my bare A6 the wires are silicon insulated which are easier to work with and also easier to damage with sharp things. My light arrived in fine shape but after 1 week of too often peaking inside it started going DD when the bezel was fully tightened. At first I thought reflector but the solder joints were low and the spacer disc is fairly tall. Then I noticed that the mcpcb notches were offset from the pill holes and sure enough when I pulled it apart there were cuts in the emitter wires. Fortunately there was enough length to recut and resolder them. To keep this from happening again I squeegeed some Fujik adhesive edit use AA or better adhesive as the Fujik proved too soft into the open spaces by the mcpcb flats. When this cures it will prevent the mcpcb from twisting with the head and shearing the wires.

If I understand you correctly, you want to unscrew the bezel and remove the lens and reflector.

Be very careful when you do this. There is a white plastic centering ring placed over the emitter. Sometimes when you turn the bezel, this ring, along with the lens and reflector, turn at the same time. This can cause the sharp edge of the centering ring to cut into the dome of the emitter, slicing it, and sometimes dedoming it.

You should press down on the lens with something like the eraser of a pencil when you screw or unscrew the bezel. This holds the lens, reflector, and centering ring in place so that they do not turn when you rotate the bezel.

Another tip is to let the flashlight cool before unscrewing the bezel. When the emitter is hot, its dome gets softer, and it easier to accidentally dedome it.

I was able to get the O-ring correctly seated by carefully putting it in place (which is precarious, but doable). I had to stretch the O-ring a bit to pop it into the small groove where it fits.

Next, I placed the centering ring over the emitter, and stacked the lens and reflector (with O-ring) on top. I lightly balanced the lens on top of the O-ring.

Lastly, I slipped a pencil (eraser first) through the bezel, and gently pressed the eraser down on the lens. By pressing down on the lens, the lens, reflector, and centering ring are held in place so they do not rotate when you screw on the bezel.

Thus, the O-ring was held in place while I slipped the bezel over the lens and screwed it back onto the head.

Hope this helps.

Rufus thanks for sharing that. Nice pics! You mind if I get that in the main post?
:slight_smile:

Is there a kind of Fujik that “cures” (gets hard like glue)?
The Fujik I have stays creamy soft forever.

I recall there has been some confusion in the past about this.

The tube sets hard, SKU 1049304

The tub is non setting, SKU 1049305

https://www.fasttech.com/search?fujik


As a tailstanding lantern you can just place a film canister (the ones you get from intl-outdoor) upside down on the light, just loose with the lid still on it (helps diffusing)

Use it however you wish. I think a better adhesive should be used at the edges. The Fujik is too soft and still allows the mcpcb to twist. If you post a link be sure to mention the post number so people with different posts per page settings can locate it.

Good tip! I was faced with the same problem and here was my solution:

I rounded off the portion of the base that was binding with a razor blade. (I need go back and drill it so that it looks more presentable.)

Actually, I don’t know what’s keeping the base attached to the reflector. The base may just fall off on its own the next time I open the head up!