(making) smallest 18650 xm-l light

[jamesearljonesisasca (jamesearljonesisascab)]

the purpose of the driver is to limit current and i know the qtc pill does that, but up to a certain tightness/compression of the qtc isnt it possible that it can send too much current to the led thereby overloading it with too much amperage. it shows 3000ma max on crees website but we know that it handles over that(my MF dropin was @3.02A and others have gotten higher readings) depending on heatsinking. the qtc pill will pass up to 10A not really sure what amps different 18650s can push out.

http://www.cree.com/products/pdf/XLampXM-L.pdf

[rizky_p]

i wish i had copper coin back here :) Nice Mod btw.

[Match]

The smallest 18650 xm-l torch, Hmm...

I'm assuming that it's to be driven to full power (@3amps). In that case, the ideal design would entail a copper tube just barely larger than the 18650 cell, with a solid connection between the head, heatsink, and body. The idea here is to use all of the torch to help dissipate heat, so threaded connections would be a hinderance. Like you've planned, using a qtc would definately help to save space, along with a very small reflector or TIR lens to help keep OAL at a minimum. Using the coin, if it's pure copper, seems like a good idea, but I think you may want something thicker with better contact with the body (I'm not sure how snug the fit is now). Interesting mod so far, keep us posted!

[jamesearljonesisasca (jamesearljonesisascab)]

looking for a p60 laser module and stumbled upon there copper heatsinks/discs. might be worth looking at.

http://laserpointerforums.com/f64/custom-copper-heatsinks-made-order-42626.html

[fishinfool]

@Match

The smallest 18650 xm-l torch, Hmm...

I'm assuming that it's to be driven to full power (@3amps). In that case, the ideal design would entail a copper tube just barely larger than the 18650 cell, with a solid connection between the head, heatsink, and body. The idea here is to use all of the torch to help dissipate heat, so threaded connections would be a hinderance. Like you've planned, using a qtc would definately help to save space, along with a very small reflector or TIR lens to help keep OAL at a minimum. Using the coin, if it's pure copper, seems like a good idea, but I think you may want something thicker with better contact with the body (I'm not sure how snug the fit is now). Interesting mod so far, keep us posted!

Why do I get the feeling that you're probably already building one in your head. lol

WWMD?

[Budgeteer]

I wonder if someone had the idea of making a 1AA powered XM-L flashlight. Since eneloops can be stressed to around 8A draw a good booster circuit could easily deliver around 2A to the led. Don't see a point having a flashlight with runtimes like 5min but heck many things were done just for the fun factor. :)

Before someone try that i'm unaware of any drivers suitable for that operation. I also think it's the cheesiest idea of all. But might be fun. I bet Match does not mind doing one just for the fun factor. Making it QTC enabled might be worthwhile.

[fishinfool]

http://www.youtube.com/watch?v=_rAHnwWfsaY

[arenat]

"I wonder if someone had the idea of making a 1AA powered XM-L flashlight..."

I did an XM-L AA /14500 powered and it's not a circus's torch , is my current EDC despite the ugly beam due the emitter being undomed...

http://budgetlightforum.cz.cc/node/1600

[hansi22]

@UDO

Trustfire TR-801 will be chosen as the host (as is already small 18650 light).

And just when I thought there is no more light I need to purchase...

[arenat]

@oldbobk

It occurred to me that a really budget way to incorporate QTC, on a temporary basis, would be to sandwich it between two of the batteries in a multi-battery host.

Bob K

@SashiX

Hm, XML with QTC, smallest body, 18650... interesting, very interesting :p Want to see more projects with QTC.

agree , also it led to the next step, the qtc cell...

[Budgeteer]

I see many problems to make a QTC switch reliable in non twistie flashlights. Just switching battery might be a disaster (different battery length). I'm sure somone tought somethng to counter the effect... yes/no/Foy?

[UDO]

I finally got XM-L from lck-led so I finished modding TR-801. Works great, doesnt screew all the way, but that will be fixed in the future (with some switch modifications). I know my soldering skills are not so good, but hey it works and it works great - QTC even with spring in the tail is great for adjusting brightness (stiff spring), I also tried direct drive and it pulls just a little under 3A@4,1V. In the end I used alumunium coin - 20 haliers (old slovakian currency - 0,2 koruna) on which I mounted XM-L.

Pics (yea I really need to get some new reflectors):

You are right Budgeteer - we need to invent more reliable way to use QTC inside the flashlight... I am using foam rings around QTC, so far so good, but I know that isnt really reliable. Maybe sendwich betwen two plates would be better...

EDIT: I tested it for 15 minutes at about 2/3 brightness and the whole body does get quite hot - around 40-45 degrees C. So heat transfer seems ok.

[Piers]

Looks good, nice job :)

[Davx]

Really a good job. The only problems could be the heat transfer at full power.

[Budgeteer]

Bravo stari!

I knew you'll end up doing it nicely. How's the XM-L tint? I have not tried yet mine. Only the ones form LEDDNA... yellowish to green tint.

[UDO]

Tint is very nice white imho near 6000k - comparison:

first skyray s-a1, second modded tr-801, third c30 (with P4 led):

[Budgeteer]

No color tendency of the corona of any kind?

[Foy]

There's actually a forum devoted to laser pointers?

Foy

[Budgeteer]

???! Yep there is... http://laserpointerforums.com/

[Foy]

There's a lot of action over there. Over 4,000 active viewers? I would have imagined.

mustgetoutmoreFoy