5W direct drive question- Now with Pics - McLux

Just got my McLux parts today and was wondering what everyone's thoughts and experiences were with direct driveing a U2TW Vf 6.39-6.87V(or similar) 5W LS with 3x123 lithiums? has anyone done this?
Im scared to do it as I've lost 5 watters before with too much current useing Nicads within range of an LS's Vf spec and with proper heatsinking. (could have been a bum set of parts for me but I'm gun shy now).
If I used a Resistor in series... what would you guys reccomend? I can figure this out but was interested in what other folks have been using with track record proven success. Has anyone lost a 5W LS in this config?
If I was to go to a buck\boost or just buck converter, are there any good choices that come close to fitting the BB series converters?

What are all the other DIY'ers with 3x123's doing?

Thanks in advance! /ubbthreads/images/graemlins/grin.gif

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

Either use a Wizard circuit made by dat2zip, or use a resistor to step it down... as for the value of the resistor, I'm unsure.

3 new 123s will blow the LS immediately. Maybe 1/2 used 123s will do better.

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

Dat2Zip is mum on ship date for the Wizard. To limit current simply in this case, use a 2 Ohm 5 Watt resistor in series and sit it against the head metal for heat sinking. This will result in about 750mA of current and will dissipate about 1W of heat. This is assuming an original load voltage of about 8V for the 3-123 Lithiums (which empiricly is what I have seen).

Hotfoot claims to be using a 5W white direct drive! I don't have the gumption to try this...

You could use one of the BadBoy 700/750 boards with 2-123 cells in that 3 cell handle with a dummy as an alternate.

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

All Bulk Mods are Direct Drive i believe, and i run my 5w Luxeons direct drive also. all my 5W's are white.

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

If you want to limit it, use a 2.2 ohm 5 watt wire-wound resistor. You can get them at Fry's Electronics, or off of Elektrolumens' web site. I believe you may want to ask this question to Mr. Bulk, as he has done the direct drive 3x123 thing before, but I don't know what the bins he used were.

Re: 5W direct drive question with 3x123A @ 9V - Mc

Thanks for all the advice everyone... I had planned and would prefer to wait and use the wizard converter but now that I have all the other parts.... I have no self control. /ubbthreads/images/graemlins/grin.gif
Must build it.

When the wizard comes out I may switch the light over to regulation.
What's interesting to me is that the 5W LS as you all know is spec'd for 700mA.
My parts, (U2TW Vf 6.39-6.87V) will not pull the full 700mA until I reach 7.8v using a regulated bench supply.
So I will need to drop 1.2v with the resistor.
I might be able to get away using a large Diode for the drop and add reverse polarity protection while I'm at it.

Why would Lumileds set a Vf of 6.39-6.87V for this part?
Is this how they are getting the 1000hr vs. the 500hr?
Or am I being simply too strict on Lumileds QC dept who's tolerences may not be that tight?

If I find the resistor today somewhere here locally I may have My 5W McLux tonight!! I'm also building a 1W McLux with a Madmax... This one should be ready tonight!!

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

[ QUOTE ]
Nerd said:

3 new 123s will blow the LS immediately.

[/ QUOTE ]

WOW ! Maybe I should quit turning on my SGK, and warn all the Nexneedle owners to do the same.. /ubbthreads/images/graemlins/yellowlaugh.gif

Re: 5W direct drive question with 3x123A @ 9V - Mc

Hey Slick, a little off topic here, but I noticed your sig and had to laugh. I was reading (for real) that Air Force One no longer serves "French Fries or French Toast" to the President and his staff.
Both recipes were modified slightly by the cook and now Air Force One only serves "Freedom Fries and Freedom Toast".
The Freedom Toast has cream cheese in the middle and the Freedom Fries had no salt or something like that. /ubbthreads/images/graemlins/grin.gif

Back on topic...
The direct drive mods for your SGK and the Nexneedle...
Do you know if only Vf bins were used that support a voltage much closer to the 9v?

Re: 5W direct drive question with 3x123A @ 9V - Mc

[ QUOTE ]
flash.... said:
Hey Slick, a little off topic here, but I noticed your sig and had to laugh. I was reading (for real) that Air Force One no longer serves "French Fries or French Toast" to the President and his staff.
Both recipes were modified slightly by the cook and now Air Force One only serves "Freedom Fries and Freedom Toast".
The Freedom Toast has cream cheese in the middle and the Freedom Fries had no salt or something like that. /ubbthreads/images/graemlins/grin.gif

Back on topic...
The direct drive mods for your SGK and the Nexneedle...
Do you know if only Vf bins were used that support a voltage much closer to the 9v?

[/ QUOTE ]

Heh heh.. I enjoy my little "dig" on the French because the liberal press tries to make them out to be on some "ethical high-ground" for not supporting the removal of Saddam. In reality, the french are the ones who are taking advantage of trade sanctions against Iraq and are engaged in heavy business with them. Of course they don't want Saddam overthrown, they'll lose their investments!

Anyways, I digress... back to the *real* topic - I don't have any idea what bin the 5W Luxeons came from that I used to build my SGK's. I only built a few in cyan & royal blue, and those emitters came from "open reels" of undertermined bin.

That being the case, I haven't ever had a 5W Luxeon "burn up" imediately or otherwise from being operated on 3x123's. Of course, I don't do extended runs in lights with insufficient mass to pipe heat away from the emitter. I took a current flow reading from one of my SGK's that had 90% fresh batteries and I noted ~1.2amps

As a side note, I build direct-drive (NO resistor) 5W mods that are driven by 6AA NiMh batteries. Current flow on the 6AA's runs ~750 - 850mA, which is close enough to spec for me to omit the use of resistors. I believe that resistors find favor with modders who sell their wares and offer a warranty on the LS.

Please note that these are MY experiences, and your results may vary.. I'm not saying your emitter won't fry, only that none of mine have (yet).

Re: 5W direct drive question with 3x123A @ 9V - Mc

Using a diode for the voltage drop may be problematic. First, a diode behavior for current throughput is very non linear around the drop voltage. If you use a resistor, then not only is this much simpler, but you won't have to worry about voltage drop as the batteries age because the current will just reduce. With a diode you may wind up shutting off current dramatically as the Vf of the Luxeon and your drop diode is not reached. With a resistor, even the initial current due to fresh battery voltage will be ameliorated in a linear fashion.

Remember that fresh batteries have a no load voltage (9V for the 123s) and a load voltage. The load voltage in this case is about 7.8 - 8.2 V (depending on manufacturer) for a fresh battery set. This means your drop is significantly smaller then the 1.2V you mentioned.

The 750mA current using 2 Ohm 5W Metal Film resistor I recommened was found using both a bench supply and using fresh 3-123 lithiums at 8.2 V and using a 6.4 Vf 5W Luxeon.

If you really want to stay in spec, use LEDModMan's recommendation. Both will be in spec within a few minutes of use due to battery voltage drop.

Re: 5W direct drive question with 3x123A @ 9V - Mc

I just wouldn't recommend using NiCD's direct drive. Otherwise, you should be fine. The only disadvantage to direct driving the 5W at 9v is that it *could* reduce it's life. This hasn't yet been determined by anyone, but it is a possibility. Have fun!

Re: 5W direct drive question with 3x123A @ 9V - Mc

Ok I could not stand it and took the plunge!
5W direct drive... no resistor, no nuttin.

WOW! Holy Mother of Pearl!! McLux light bright!!!
Man, it's just a mean mini Monster light sooo bright. It gets warm fast... an excellent example of how well the McLux head draws the heat away from that emitter.

I love it! Ok, so intermittant use only.. still will scare the bark off a tree! /ubbthreads/images/graemlins/grin.gif

Thanks to the entire Skunk Lights team! These two new McLux's are now my favorite lights. and I have a new EDC. /ubbthreads/images/graemlins/grin.gif

Re: 5W direct drive question with 3x123A @ 9V - Mc

flash...

Wow, sounds like way too much fun...

I guess I better pay my dues before I can announce anything.

As soon as I officially get a check off here, I do have some announcements to make.

Wayne

Re: 5W direct drive question with 3x123A @ 9V - Mc

flash,

are you using the nx05 optics or the mcflood reflector? i'm curious as to how the 5watt performs with them, since i also have a 3x123 mclux here thats waiting for a 5watt to be put into it...

Re: 5W direct drive question with 3x123A @ 9V - Mc

announcements!!!

oh...i like that!

Re: 5W direct drive question with 3x123A @ 9V - Mc

/ubbthreads/images/graemlins/buttrock.gif /ubbthreads/images/graemlins/yellowlaugh.gif /ubbthreads/images/graemlins/cool.gif

Re: 5W direct drive question with 3x123A @ 9V - Mc

nqwan... sorry for the delay... I was camping. /ubbthreads/images/graemlins/grin.gif
I have discovered that serious flashlights are required "tools" of a good camper. And all of the lights pictured below are great lights to use! The 3x123 DD McLux was easily the most powerfull light that anyone brought in my group. I was amazed at how well it lit up the under canopy of the trees to watch the racoons plot robbery of my food stash.. /ubbthreads/images/graemlins/wink.gif
Anyhow, yes I'm using the NX05 optics in my McLux's.
Heres a couple of pictures.

A little glow powder...


Good comparason pic here.. I ordered my McLux belt clips for these late, so they will be on soon. I would love to have the 3x123 light in the same finish as the 1x123 McLux.


My new EDC. /ubbthreads/images/graemlins/grin.gif This light is Sharp!



The beam shot on the right is the direct drive 5W 3x123 McLux , "A monster in a very small package" on the left:my E2e with CM's awesome 667mA 5W KL1 Mod, also very bright and regulated for longer use applications. The beam shots were taken at 6 feet.
These lights are both awesome in actual use. This pic is after I used the 3x123 over the weekend at camping while the E2e has new SF 123's in... I Also noticed that after the first few uses... I was able to leave the DD 3x123 on longer and longer as the 123's came down in voltage just a bit. The interesting part is the overall light output does not seem to have been equally reduced by any measurable level. Of course this is my best eye judgment but, it's good enough for me.


Awesome Work... The McLux DIY kits rock!!!
Thanks again to the entire Skunk Lights team for making these lights possible!

Re: 5W direct drive question with 3x123A @ 9V - Mc

how did you apply the glow powder? and where did you apply it? i'm interested in using glow powder, but am clueless on how or where to apply it. Thx

Re: 5W direct drive question with 3x123A @ 9V - McLux DIY

[ QUOTE ]
Slick said:
[ QUOTE ]
Nerd said:

3 new 123s will blow the LS immediately.

[/ QUOTE ]

WOW ! Maybe I should quit turning on my SGK, and warn all the Nexneedle owners to do the same.. /ubbthreads/images/graemlins/yellowlaugh.gif

[/ QUOTE ]

Aww come on... he's got a 6.xx volts forward V 5 watt, 9 volts "theoretically" would have blown it. Better safe than sorry. /ubbthreads/images/graemlins/icon15.gif

Re: 5W direct drive question with 3x123A @ 9V - Mc

Awesome! Thanks for the pics! I just received a 5W HD LS emitter so I will putting it into my 3x123 McLux as soon as I get a chance /ubbthreads/images/graemlins/grin.gif