FW3A mod thread. Post yours!

Any chance of making a red ?

Both FW3As I’ve modded so far had small amounts of flux on the LEDs.

I would like 1 of each CRX.

Sounds good.

Do a physical lockout. A slight turn of the head or tail achieves it easily on the FW3A. I do this by habit with all my lights as I absolutely hate parasitic drain, no matter how faint. :wink:

That doesn’t actually lock out the FW3A, because it doesn’t disconnect power.

For example… turn on the FW3A at a low level. Then start unscrewing the head from the body of the light. On mine, the light doesn’t actually stop coming out until about three full turns later, well after the O-ring is exposed.

Alternately, take the head off completely… then screw it on. How far does it get before the light blinks to indicate that power has been connected?

It’s designed to be in a completely bare aluminum host. The threads are not anodized, nor are they meant to be. Twisting it a quarter turn doesn’t really do anything except break contact for the switch ring.

Ah, interesting. I did what you suggested and saw that the illumination kept going even after a full turn of the tail. However, turning the head caused it to cut out right away… just like a mechanical lockout… I’m guessing there’s no difference in parasitic drain, but so low to be negligible, right?
Saw this post in the other FW3A companion thread: LINK.

I think you have some dirty threads or something, when I unscrew the head a bit when the light is on, it stays on but disables the switch. Of course when a electrical disconnection occurs for a very short time during the unscrewing action , the light will go out.

Got mine yesterday, had it for about 5 hours before tearing it apart and trying some reflows. The stock X-PL HI had a great beam profile but I really have been spoiled by high CRI and warmer tints. Mine were definitely a bit north of 5000K.

First were 4500K 219Bs from a PL47 (sw45 then I think?), and on 8x7135 they were fine but at full turbo with a NCR18650GA charged to only 3.9v they would go very purple. Tint was nice and output surprising good even at max ramp, similar beam to these emitters in any other TIR light.

Wanted something I could run at turbo without as much heat and not have to worry about killing the emitters so shaved LH351D 5000K “dogfarts” were up next. Tint is obviously still more green than the 219Bs (isn’t everything?) but better than 219C 5000K 90CRI for sure and just about any emitter not known for being super low/negative duv. Beam profile is pretty floody, especially with the frosted optic but the shaving definitely makes these emitters more throwy and I really don’t have any desire to swap to a throwier optic right now. Heat is probably a bit more than the XPL HIs but nothing outrageous for a light this small. Output is visually similar to stock emitters, just with a wider beam. Wider hotspot with smoother transition to a more narrow spill when compared to XPL HI. Warmer CCT than stock 3Ds but still cooler than my 4500K SC600.

As proposed in other FW3A topic, the behavior difference may be due to presence of lube on the threads. Given the initial contact trouble I had with mine out of the box, which cleared up with a few loosen/tighten movements. I’m guessing that this action pushed away enough lube to make a good contact but then breaks contact with a slight rotation of the tail cap, instead of maintaining current flow for up to 3 full loosening turns.

I’m already abusing this light even more than I had planned to… :smiling_imp:

Now running 2x stock XP-L HI 3D and 1x LH351D 5000K sliced. Output and throw kept pretty intact from the 2 XPLs while the 351D definitely helps the temp and tint a bit for my preferences.

Can only really compare the brightness of each individual emitter on the very low end of the ramp but from the tests I’ve seen the Vf on these should actually be pretty similar. Frosted lens means I can only see differences in temp/tint with the light an inch or less from a white surface.

The LH351Ds are 70CRI, correct? Then, yes, the VF is pretty similar.

No. Dogfarts are a very specific product… Samsung LH351D SPHWHTL3DA0GF4RTS6. They’re 90 CRI, not 70 CRI.

https://www.arrow.com/en/products/sphwhtl3da0gf4rts6/samsung-electronics

Nope, 90CRI “DOGFARTS” and now I realize the Vf/current charts I was looking at were actually for LH351 C so back to the drawing board I guess.

Yeah, the LH351Ds 90CRI have quite the lower VF.

Didn’t notice the DOGFARTS.


Just some GITD tape. No, I didn’t coat the light in black — it’s still gray (just a lighting trick due to contrast balance to show GITD tape). :wink:

At first I had a wider band on the tube, then shortened it… and now I’m thinking I may narrow the tube strip to match the width of the tail cap strip, or take it off altogether (leaving just the tail cap). The tail cap one was cut to fit nicely in the groove, so no concern of handling that might dislodge it.

EDIT:
Yeah, thinner is better.

Also discovered that 1 strip is more aesthetically pleasing:

/\ . That looks neat! :beer:

I modded mine, even more than I really wanted to but one thing lead to another.

I put a LED4Power triple MCPCB in (1.5mm) with 3x Nichia 219B. I replaced the wires with 20G and reflashed the light with TK’s 219B version of Anduril. I also installed a drilled optic with 3x orange trits.

Some modding tips for this light:

My LED4Power triple MCPCB had to be VERY lightly sanded. The flat edges of the MCPCB stuck out just enough to not want to drop in. I used 1000 grit and it took like 2 minutes to just smooth those edges.

I tried to use the stock wires but they are cut to the exact length the stock MCPCB needs and my positive lead could not reach the pad. If you replace the MCPCB have a contingency plan to replace the wires too if they don’t reach!

When you take the driver out you will see the LED wires are right next to each other dead center on the board. When I went to de-solder the negative lead it’s hard to get my usual chisel tip in there and I ended up pulling up the pad just a little as the wire came free. So maybe use extra flux and a smaller tip you have one. Clean it with a toothbrush and alcohol after.

When you re-solder the leads they need to be straight up. The driver sits right against the shelf so you wont be able to tuck them anywhere and if they wick too much solder cause you used a too fat tip like me then it wont want to sit flush and feed through the hole. I had to re-solder mine a second time and make sure they were straight up and down.

The LED positive wire sits a bit close to the MCU. I was still able to fit the clip on with my larger 20G wire in place but it was resting against it and just barely had room.


On an separate note, can someone try to torch/bake this anno to see what color is changes to? Take one for the team :slight_smile:

Thanks! It’s the cheapest, fastest mod you could probably do. :wink: I’d like to do a GITD optic insert, but sometime later on.

Modded the FW3A Cheatsheet :D