I'm planning on building a 445 laser using a single 18650. Using this driver from dx - DealExtreme: $2.36 2.7V~6V 3W Cree Circuit Board for Flashlights (15mm*2.7mm) - could i realistically give an xj-a140 diode anough juice to hit 1W? I know there's a bunch of variables in the chances of a good or bad diode, blah blah blah. but does that driver have a small enough drop to deliver 4-4.2V 1050mA when the 18650 is fully charged? if i have to, then id go ahead and spend more money on cr123a's... but im lazy *grumblegrumble* and tight on money.

DealExtreme: $16.58 AMC7135 1050mA Regulated Circuit Board for DIY Flashlights 10-Pack
This one is supposed to work very well.
I have been told that you NEED to use cr123a's for the 445 diodes.
808 can use an 18650 because this is a buck driver and will power the (~2v) 808nm.
the 445 won't have enough Vout once the 18650 sags even any.
Cr123a's are pretty cheap on DX but the shipping takes forEVER!!! I try to anticipate what I will need in 3 weeks :P
Happy lazing bro!

thanks, that helps a ton. im pretty sure that's the same thing in a ten-pack. im already ordering some stuff from DX for my laser, so the shipping doesnt bother me. will two CR123A's fit in a DX 3405 host?

I'm pretty sure they will but 2 protected cells will be a little longer than the 1 protected 18650 (about 2mm total I think)
might have to shave down the clicky retaining "screw" in the endcap.
I did that with a cheap costco host for a buddy and it worked all right, just a pain in the butt to change out the switch ^_^
I figure the 10 pack will be handy (one should show up here any day now) because I can make 1400mA drivers by "piggybacking" one 7153 on top of another. These diodes can take punishment!
I also ordered a DealExtreme: $3.60 16-Mode 3W 3.7V 7135 Circuit Board for Cree and SSC Emitters (3.7V 1000mA Output) but that is just because I wanted a novelty driver with a lot to play with (low mode might be nice to adjust the focus)
These things have a beam that can be seen for miles, as a signaling device (with SOS) it could prove invaluable.
The one I posted was for a 17mm driver though, just noticed that. Kind of a good thing to know before you order

oh. whoops. that host is big enough for either from what i can tell. DX sells 1400mA drivers too, just in a 20-pack which is irritating.
multi-mode sounds great, but 16 modes?? that seems like too many for even novelty use! oh well, at least it has groups. seems complicated. but interesting/fun.
isn't 3.7V not enough for a 445? i guess it depends on the power you're trying to get out of it.... shows how little ive learned from stalking the forums. cant wait to get my hands on one of these crazy diodes.
the 3405 is originally supposed to be for 3X AAAs, so from whatever post i might have seen the 18650 alteration from, the endcap is already messed with. that would be quite a switch but im willing to take that chance ^.^ thanks for all the help!

should be able to fit the cr123a's in if it is the one Jayrob does, I'm pretty sure it has some extra space in there lol.
I figure, if a cop/fish and wildlife officer tries to take my laser away I have a very valid argument about signaling and use in an emergency situation ^_^
The low power as a start is a great thing too, should be below lasing threshold so I don't know if it will work for focusing but medium will give you a pointer/burner without chewing batteries too bad or having the same short duty cycles lol (90 seconds isn't that short I guess).
I'm looking forward to a "police strobe" 445 beam

The MXDL host won't fit 2XCR123s unless you do the "18650 mod" to it. This thread explains how to mod the tail cap to accept an 18650. Once that is done, it should fit 2XCR123s

Good luck!!

auto- because a 1W really needs to be more dangerous lol. maybe a grenade launcher is in order after that police strobe! J/K. about that low power start though... a great idea. once i get this made, i might try to drill a hole in the side of the MXDL to put a small pot on there, connected up to the final output. that way i can can mess with the focus and tune it down quickly if a teacher sees it at school or something... lol. i already had my backpack searched last year because a teacher saw my 50mW greenie... high schools too strict. i have a slight feeling they wont allow one of these.
tuning down for a normal blue pointer though? YES. <-good idea

kevlar- thanks for the heads up. so the DX driver can accept 8.4V and tune it down to the 4.5ish it needs? i see a diode on there so thats good.

Best not to bring to school unless you bring enough goggles for everyone..... That might get pricey.

thats where a pot to tune down the power is applicable.

So is there any driver we can use for 445nm with 18650 besides the drivers people sell on here? (drlava, etc)

Theres always the DDL driver (DIY)...

Yeah, you can use the DDL but it has it's own problems and isn't as efficient as it could be
I still haven't tried the 7135 chips but I'm sure you could scavenge chips off of the DX ones and make your own driver on a piece of stripboard (add diodes and capacitors for safety even)
Might even be able to make it small enough to fit into an aixiz module lol.
@the bucketmouse:
That is what we are discussing.... 4 7135 chips will give you 1.4amps, good power for a casio diode.
I'm still not sure about the driver's stability though, LEDs are a lot more robust than even the casio diodes so I don't know if they will toss voltage spikes at it or not.
A 16v 47F electrolytic cap to take the big spikes and a 1F ceremic plate cap to smooth the little stuff might increase the diode's longevity by a lot if the drivers on DX are too "messy".
Just solder them onto/near the diode (parallel)
I am not an expert/have not tried any of this stuff/not responsible for you killing your diode.
This is all speculation and I don't have the components yet nor the oscilloscope to confirm/disprove these ideas ^_^
@Horhay: Turning down the pot won't work because there would be too much current flowing through it, you would need about a 3 watt rheostat to handle what it needs for resistance and they can be spendy. The lasing threshold of the 445s is about 200-250mA, below that and it is very dim, above it and it is still VERY dangerous. IE: Wear safety goggles around it because it can still do a pile of damage!

auto, didnt you mention before that the voltage drop on the 7135 drivers is too much for a single 18650? 4 chips would make a helluva laser, but IMHO, 3 would be safer unless there is a huge heatsink on that sucker. 1050mA is reasonable for a small heatsink.

lucky me, i happen to have a 3 watt 25 ohm rheostat lying around from a DDL driver from a dead PHR...^_^ too bad those things are obnoxiously ginormous...

Ugh, I hear that. Why can't "they" just make a small magical 3 watt rheostat and call it a day eh? lol
The 140s can handle a ton of current, I heard of one guy on the site driving his labby to 2.8 amps I'm pretty sure it was TEC cooled though lol
Yeah, the voltage drop isn't really the problem though, the 18650 will only give you 4.2v max and that is only the instant you pull it out of a good charger and apply a load XD
2 cr123a's are giving you 8.2 which isn't ideal either because the driver will turn the extra juice into heat. an 18650 would work well for a red or an 808nm (3.2v and 2v respectively I think) but that doesn't really work in this application
Hate to admit it but I think the flex 5 and microboost are the most efficient options for these diode/battery combinations.
I'm going to play with the amc7135 drivers for a while though because I am a tightwad and think 23 bucks is too much for something that I could stick up my nose.....

^amen to that^ post how well it works! i havent dont too much with the 7135s so id be really interested to know how they would work in this situation.