SF L1 mod,worthwhile??

I have a SF L1 on its way to me.I had one before and was PO'd by the purple beam.Looking round in my bit box I found a Q2JW HD Lumiled,if I put this in,would the mod be worth the effort(would it be significantly better)?
Also,how much hassle would it be to do?Is it de-solder/re-solder?
Any links to strip down threads?
Thanks folks-Phil. /ubbthreads/images/graemlins/smile.gif

A Q2 would be toward the opposite extreme, maybe yellowish-greenish though the old binning system did not give enough granularity that a "2" tint can be green to white in my experience. Do you have a preference for warmer or cooler tint? If you like warmer tints, then the Q2 may be worth the effort. If you like something cooler then my guess is that you will not like the result.

Modifying is rather straightforward after you get the bezel ring off. Sometimes this can be a bear (gobs of epoxy), sometimes they can just twist off almost using your bare hands. Soldering and desoldering is pretty straightforward if you have some soldering experience. If you're transplanting a high dome, centering could be the major time consumer. Just try to get the LED as close to center as possible and then cross your fingers. If you're off, then it becomes an iteration process to get the LED centered. Kinda hard to describe unless you've done this before. It's part of the CPF "initiation" that once you successfully center a high dome to an optic, you move up the ladder from being an apprentice modder /ubbthreads/images/graemlins/grin.gif

CM

I found the L1 to be a very nice light once I replaced the LED. Like yours, mine was purpleish and not very bright. Now it is nice and bright and white , and the low beam is more usable too. I put a 3 watt SWOK in mine because that's what I have available.

Daniel

Anyone presently doing mods using 3 watt high domes? If so, approximate cost?
Thanks,
Jim

I think the L1 platform is the best modding platform currently, but then I am really biased and after a specific tool. The two stage switch is elegant in design and function. The size of the light is great in the hand. What can I say, I like this light.

3 watter works well with the stock circuit?

To my simple mind and even simpler testing methods, the Lux III's seem to behave every bit as well as 1W Luxeons at current drive levels down in the area of the 1W specs. Their Vf drops accordingly and the output looks good to me! This is an opinion, nothing more or nothing less. If others have had other experience with underdriven Lux III's it would be good to hear.

I have several lights with Lux III that are driven under spec. I should have used 1 watt LEDs but I really like knowing that the color will be close to white. I had the LuxIII's sitting around anyway.

I really like the result of putting a SW0K in my L1. I get about 30 lumens from it now, compared to Surefire's claim of 15. It's very white and looks twice as bright too.

Intuition tells me that the 3 watt LED with a Vf in the K bin (3.51V - 3.75V) will be closer to a J (3.27V - 3.51V) when driven at lower current levels. Thsi should result in lower battery drain. I'll have to check that out, though I don't have a good bench top heat sink setup for 3 watt LEDs at full current (700ma).

Someone mentioned a 100mv increase was needed to drive an extra 100ma once the Vf was reached. I don't know if that's accurate.

Daniel

Daniel,

In a few tests I did on a varible power supply, the Vf on the Lux III's did drop as you suggest. Further the luminous output at lower Vins was comperable to what one might expect. I tested a couple R2H's against some TW0J's and they were close in vF and light output in the current ranges of the 1W realm but the TW0J did seem to pull away in output at the higher Lux III current ranges. Granted there is enough variation within a single bin and model of Luxeon to put a real damper on any value to a head to head comparison of just 2 LED's.

[ QUOTE ]
McGizmo said:
...If others have had other experience with underdriven Lux III's it would be good to hear.

[/ QUOTE ]

I concur with your findings as I've done several L1 mods at stock bias. So for all practical purposes, I think it's safe to say that the two are probably interchangeable, even at the Lux III levels. As far as longevity of the 1W parts driven at 700mA, well, who cares? /ubbthreads/images/graemlins/grin.gif

Is it hard to boost the stock drive?

It's a minor surgery. You have to take some metal off to get at the circuit since it is press fit in there. I've never done it but I have taken the circuit board out for another very famous fella here on CPF.

CM

I'd like to see some pictures of how to get at the circuit.

I agree the L1 is a fine light, and if you have a poor emitter a swap is an easy and VERY effective way to get more out of it.

Centering the white emitters is a little easier than pure color emitters, IMO. If you put just a dab of artic silver (grease, not epoxy) under the emitter, it will stay where you put it while centering. Drop the board and emitter in the head and place the optic over the emitter. Move it around with your fingers until the yellow phosphor COMPLETELY fills the optic (this is what makes white emitters easier). Carefully remove the optic, then very carefully remove the board/emitter, and gently solder the emitter down. The re-assemble and re-check the centering. This has been a very effective technique for me, YMMV.

Is it the general concensus the replace the stock 1 watter with another 1 watter or go with the 3watters? On low, my white L1 is a very nasty green. Will a nice bin 3watter on low be as terribly tinted?

My limited experience with SWOK binned Lux III leds was that they do not shift badly when run at lower current levels. Neither did the TV1K LEDs. I think the V1 shifted more than the WO, but that's purely subjective.

Daniel

I managed to extract the coffin from my L1 in a mostly reversible manner. I was expecting that the circuit would be similar to the KL1 circuit, but it's considerably different. What resistors need to be stacked to boost it?