Hot air gun and fine tweezers, being careful to not let the tiny emitter blow away. Pretty tricky stuff.
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Iāve wondered about those weird 20mm 4x3535 boards for a whileā¦ While iron was out for (unsuccessful) DW4 repair, I reflowed 4x 519a onto one of those MPCBs and soldered it into my L6 with an Emisar driver. Waiting on an 1*26650 tube solution.
Without the proper tube, I had to use paperclip to complete the circuit between the 1x26650 and the end of the tube. MASSIVE doughnut beamā¦ Whoops, at least I satisfied my curiosity 
Next step is to dedome and maybe try to seat the reflector lower to get a better beam. Have DC fix which I might try, and finally, if it still looks terribleā¦ A GT FC40
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I can mail you some 0402 LEDs if you want to try again.
Send me a PM if you are interested.
If this happed to me, I would put some flux on both sides of the LED and heat up the solder with a fine point soldering tip. If that didnāt work, I would removed the LED by placing a soldering iron on both sides and lift it out. Then clean up the area with isopropyl alcohol and re-solder the LED into place.
Most likely the LED is fine, itās just the connection is bad from my experience with my lighted switches.
I wonder if it would work better if using LEDs that have a larger light-emitting area, like the XHP35HI or SFS80. There would probably still be a donut hole but it would be closer to that of version one XHP emitters.
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First time ever reflowing. After 1.5 hours or so, Iāve reflowed a Luxeon 2835N 1800K into my Armytek Wizard (non-pro) and an SFT40 into my Nitefox MC5.
The former was due to my curiosity to see a Wizard warmer than the Nichia Warm, and the latter was due to my frustrations with the Thrunite Throwerās unstable output (Iām pretty sure the Nitefox MC5 had a [boost? buck? donāt exactly know] driver inside when I opened it, and better regulation when I use it) ā the modded headlamp appears to throw farther than my W1 DW4. Both are working perfectly with no problems, and I can finally see the appeal of modding your own light ā this is exciting!
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Congrats! Itās pretty liberating to not care about stock LED options knowing that you can swap in whatever you desire (although some lights will be harder than others to mod).
Not sure this ābelongsā here but figured, why not? Not really on par with true modding, but it does look different and I dig it. Ordered some GITD tape from Ali a while back. Good thermal resistance, (it doesnāt wither in direct turbo beam path) so I decided to cut a little strip and place it on the inner wall in the head of my IF25A EDC.
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Nice 
. Where do you get those 4x3535 boards?
@RightHandedMan Nice work! Army Tek lights can be a bear to get into so big thumbs up for your success!
Welcome to the rabbit holeā¦
Oh yeah I donāt doubt that a die with a larger light-emitting surface area would cause less of a doughnut. Trying to drop the reflector down lower but currently got some issues with the solder joints fouling on the reflector, Iāll re-solder them as flat as possible and try again.
I think this one came from AliExpress from āHotRed Official Storeā. Search for ā20mm 3535 4chips 12v copper starā, should get a bunch of results.
Iāve seen them on Kaidomain too.
Make sure to also put something between the solder and reflector, like a bit of kapton tape (even scotch tape will work if you donāt have a better alternative). Iāve fried a driver after shorting out through the reflector.
Or if feasible, grind down the width of the bottom of the reflector so it doesnāt touch the MCPCB solder joints. This would also allow the reflector to sit as low as possible.
I recently just did that with a reflector (Replacement Aluminum Reflector Cup):
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Thanks Found emā¦ Ali has some other interesting multi 3535 boards too. Iāve been wanting to do a desk lamp with 519a and one of those 20x boards would probably work great. Those 5 channel 25x boards are pretty intriguing also.
What did you grind it down with? I tried to do it with my dremel and a sanding drum but it was going super slowly.
I used a Dremel with a router bit: Dremel 654 Straight Router
Probably not ideal, but it got the job done and didnāt heat the reflector up much. Took about 10 minutes to do.
Sofirn HS10, removed a dedomed 4500K 519a and installed a domed 5700K 519a:
Several more HS10 LED swaps in this album:
Both lights on medium, the 519a has a wider beam and more lumens, but less lux:
Jon, I forget what those look like inside. You havenāt pulled the driver before, have you? Iām wondering if the SP10 Pro driver would fit. I think this would be my dream headlamp if that were the case.
dont know, Ive only been this deep:
https://i.imgur.com/9hWz8Xv.jpg
They do have a ramping UI, that works well enough,
plus built in charging, and the button has an LED that switches from green to red when the battery gets low.
no Anduril Disco modes thoughā¦ 
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