(making) smallest 18650 xm-l light

36 posts / 0 new
Last post

Pages

UDO
Offline
Last seen: 8 months 4 days ago
Joined: 10/06/2010 - 14:10
Posts: 224
Location: Slovenia
(making) smallest 18650 xm-l light

The plan is to make as small as possible 18650 light with ability to run xm-l T6 led to their full potential. Because of the size limit there will be no driver, the light output will be controlled with a help of QTC material, so the XM-L will essentially be direct driven. Trustfire TR-801 will be chosen as the host (as is already small 18650 light). I removed the pill and the head, but kept the reflector and the ring that holds the reflector. XML led will be mounted on a 0,05 € cent copper coin (will screew in nicely when I will sharpen the edge of the coin) and a small hole will be drilled to connect a + from battery to the led (the back of the coin will be insulated).

I will post the future progress (I still dont have the XM-L) here. The idea is to have 18650 light as EDC (my EDC now is Skyray s-a1 and it looks like this 18650 light will be even smaller than Skyray). If you have some suggestions or questions please replay. What is the smallest known 18650 light?

jamesearljonesi...
jamesearljonesisascab's picture
Offline
Last seen: 2 weeks 3 days ago
Joined: 03/16/2011 - 00:02
Posts: 1039
Location: US

Nice project there. im curious how it will do being direct driven. i would probably polish the coin where it will contact the led die and do thermal paste/glue. where was the qtc going to go? on the positive side of the battery under the coin or on the negative spring side? keep us updated thanks!

03/04/16 

 

8 lives left

SashiX
SashiX's picture
Offline
Last seen: 7 years 9 months ago
Joined: 10/07/2010 - 15:46
Posts: 2045
Location: Spain

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

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

I knew youre going the DIY route sooner or later. Smile

Be sure to file down the coin completely. Don't know where you live but in my surroundings we have a small company named BAR-METAL that can get you a coin shaped chunk of copper for a coffee. Smile

Check also OBI or similar shops. The QTC will be insterted in the tailcap i guess?

Why did you remove the pill? Parhaps you can rather shorten the reflector if size is the issue.

You can get rid of the tailcap spring and redo the tailcap for the QTC and get some space back. double coin with some spring to tweak the desirted compression for the QTC to drive it properly might be the trick.

The only drawback is that it must be "calibrated" to the size of battery used.

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

HID45
HID45's picture
Offline
Last seen: 7 years 9 months ago
Joined: 04/13/2011 - 03:45
Posts: 291
Location: Finland

UDO wrote:
What is the smallest known 18650 light?

Smallest I know is Shiningbeam S-Mini.... But it seems to be 11,4cm long... So it's not the smallest one

Nice application for 5 cents. That's about only thing it is useful for... Smile 

καὶ τὸ φῶς ἐν τῇ σκοτίᾳ φαίνει καὶ ἡ σκοτία αὐτὸ οὐ κατέλαβεν

UDO
Offline
Last seen: 8 months 4 days ago
Joined: 10/06/2010 - 14:10
Posts: 224
Location: Slovenia

 where was the qtc going to go? on the positive side of the battery under the coin or on the negative spring side?

Under the coin (less wear), because the tailcap end will rotate.

Why did you remove the pill? Parhaps you can rather shorten the reflector if size is the issue.

Well the pill+led is just too big (20mm) + the pill fits nicely into another light that I have + I want a direct drive light, so the XM-L can get the amps it deserves. 

Smallest I know is Shiningbeam S-Mini.

So that is 114mm - about 17mm  more than this one will hopefully be.  If there was no need for switch (just twisty), it could be sub 90mm - but that is just too much work for me Smile

You can get rid of the tailcap spring and redo the tailcap for the QTC and get some space back. 

I have already done that... There will be no springs in this light (no space + QTC works better without springs).  It really looks like it will be a tight fit (maybe too tight)... Shortening the reflector might be a good idea if there will be a shortage of space.

arenat
Offline
Last seen: 2 years 6 months ago
Joined: 11/22/2010 - 01:00
Posts: 367
Location: Argentina

Very interesting but too extreme , 3.35 x4=13.4W in a minute if the emitter survive asbestos gloves are needed

Hrvoje
Offline
Last seen: 2 months 3 weeks ago
Joined: 02/09/2010 - 12:34
Posts: 347
Location: Croatia

Nice moddification, but 5 cent coins are coppered steel, not copper. The smallest 18650 flashlight is Xeno G95.

jamesearljonesi...
jamesearljonesisascab's picture
Offline
Last seen: 2 weeks 3 days ago
Joined: 03/16/2011 - 00:02
Posts: 1039
Location: US

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 

03/04/16 

 

8 lives left

rizky_p
rizky_p's picture
Offline
Last seen: 2 weeks 6 days ago
Joined: 03/01/2011 - 05:06
Posts: 1036
Location: Indonesia

i wish i had copper coin back here Smile Nice Mod btw.

Match
Match's picture
Offline
Last seen: 5 years 9 months ago
Joined: 11/14/2010 - 11:57
Posts: 1488
Location: South Carolina, USA

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!

jamesearljonesi...
jamesearljonesisascab's picture
Offline
Last seen: 2 weeks 3 days ago
Joined: 03/16/2011 - 00:02
Posts: 1039
Location: US

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

03/04/16 

 

8 lives left

fishinfool
fishinfool's picture
Offline
Last seen: 2 years 6 months ago
Joined: 03/09/2010 - 00:30
Posts: 4342
Location: Hilo, Hawaii

Match wrote:

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?

 

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

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. Smile

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.

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

fishinfool
fishinfool's picture
Offline
Last seen: 2 years 6 months ago
Joined: 03/09/2010 - 00:30
Posts: 4342
Location: Hilo, Hawaii

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion

arenat
Offline
Last seen: 2 years 6 months ago
Joined: 11/22/2010 - 01:00
Posts: 367
Location: Argentina

"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
Offline
Last seen: 11 months 4 days ago
Joined: 11/20/2010 - 08:50
Posts: 15

UDO wrote:

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... Laughing

arenat
Offline
Last seen: 2 years 6 months ago
Joined: 11/22/2010 - 01:00
Posts: 367
Location: Argentina

oldbobk wrote:

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 wrote:

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

 

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

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

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?

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

UDO
Offline
Last seen: 8 months 4 days ago
Joined: 10/06/2010 - 14:10
Posts: 224
Location: Slovenia

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 reflectorsSmile):

 

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
Offline
Last seen: 2 years 9 months ago
Joined: 01/18/2011 - 20:31
Posts: 896
Location: Bolton, UK

Looks good, nice job Smile

Davx
Davx's picture
Offline
Last seen: 5 years 11 months ago
Joined: 03/17/2011 - 20:29
Posts: 910
Location: Italy

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

"There are always new jobs, women, and apartments......there is only ONE BLF." - Chicago X (27/03/2012)

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

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.

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

UDO
Offline
Last seen: 8 months 4 days ago
Joined: 10/06/2010 - 14:10
Posts: 224
Location: Slovenia

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

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

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

No color tendency of the corona of any kind?

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

Foy
Foy's picture
Offline
Last seen: 6 years 9 months ago
Joined: 01/02/2011 - 17:56
Posts: 3009
Location: Las Vegas

There's actually a forum devoted to laser pointers?

Foy

No referral links and nothing embedded . . . ever.

                      &nbsp

Budgeteer
Budgeteer's picture
Offline
Last seen: 8 years 3 months ago
Joined: 08/24/2010 - 02:19
Posts: 3087
Location: Slovenia (EU)

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

kragmutt wrote:

They're gonna send you a green redcat with a black LED.

Foy
Foy's picture
Offline
Last seen: 6 years 9 months ago
Joined: 01/02/2011 - 17:56
Posts: 3009
Location: Las Vegas

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

mustgetoutmoreFoy

No referral links and nothing embedded . . . ever.

                      &nbsp

Nautic
Nautic's picture
Offline
Last seen: 2 years 7 months ago
Joined: 02/14/2010 - 14:01
Posts: 992
Location: Europe

UDO wrote:

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

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

 

You need a spacer at the led or a o-ring at the lense to do away the donut-hole

Cheap quality is good - Expensive crap isn´t

fishinfool
fishinfool's picture
Offline
Last seen: 2 years 6 months ago
Joined: 03/09/2010 - 00:30
Posts: 4342
Location: Hilo, Hawaii

 

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion

UDO
Offline
Last seen: 8 months 4 days ago
Joined: 10/06/2010 - 14:10
Posts: 224
Location: Slovenia

You need a spacer at the led or a o-ring at the lense to do away the donut-hole

Thanx. Didnt know that! I will fix it...

After receiving so many led emitters, I had to do another mod. This time the smallest 14500 light - and this one is really small at just 57mm (for comparison - well known one of the smallest AA/14500 lights tank007 e07 is 87mm long ). It has no reflector though. Reflector will be optional add-on/slide on (when I find a sutable one)... Powered by a 14500 and using QTC as current regulator, the osram led puts out more than 150 lumens (14500 in DD - a little overdriven Smile) . Its a twisty (no switch), actually the body is well known BLF delighft cut almost in half, copper coin in the end of tailcap. The 16mm led star is mounted direcly (very tight fit - I had to sand it down a litttle) in the tube. Works really nicely with QTC, those osrams are pretty bright. My craftmenship and finish arent really up to the  "Match" standard. That guy really knows what he is doing, he could easly sell his DIY lights for muchos dinaros to some CPF snobs Laughing

Pages