Build Log, interim name '30k deathray' more XM-Ls than you can shake a stick at.

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
is the dome made of one material, or is it a few layers of differing materials? I was thinking, why not carefully file down the dome and then use the epoxy you have to "wet" the sanded surface? You could do this with #1 or #2 after you have completed tests, to keep from using another new LED.

Cool project, can't wait to watch it mature =)


The dome is all silicone on the XM-Ls rather then glass or hard plastic/epoxy like on other LEDs, which presents the problem, since the only thing that likes to stick to silicone is more silicone. And I'm certainly not considering optical silicone at $800/kg with a 1kg minimum from dow-corning, lol.
For my 3rd test LED I'll have to let it cure 24 hours at room temp. The problem is that the dome on the LED will actually swell as it heats up, and shrink as it cools down, with the die at temperature, and heating everything else, the epoxy set with it at one size, and when it cooled it contracted and broke the bond between the silicone and epoxy. The only question then is, if I let it cure nice and hard, will the stresses from the CTE mismatch of the silicone dome and epoxy backfill cause any issues? Hopefully stress testing on #2 will give answers, and see if the dome stays bonded. That and I'm sure the glass-epoxy bond is on the weak side too, so any tension there could cause delamination, which adds reflections and losses, which gets me to where I was on #1.
 

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
Andddd FAIL. The epoxy backfill is getting nixed. Even with the heatsink siting on a desk fan, keeping it cold to the touch, and with the MCPCB bonded with arctic silver, and cured under a 2-ton press for a nice thin layer, the optical epoxy managed to pop the lens off from heating and expansion after just a few cycles. I ran it without the glass on, still on the fan, and felt the epoxy, quickly after shutting off the power supply, it was quite warm, not over 70C on the surface (IPA didnt hiss when I put a drop on) but probably > 50C given how it felt to touch it. So without moving air over it, and being on a cool MCPCB the epoxy very well could overheat :sick2:

In the design I was looking at, the window would be bonded to a holder with NOA which should hold the glass better then the epoxy, and keep it from popping free. But I cant see this having long-term longevity, and possibly adding 4 different chances for reflection/refraction, definitely will hurt matters. (dome-> gap -> epoxy ->gap-> UCL window) Though the dome did stay bonded though the testing. But who knows if the stress of not letting it expand as it wants to could hurt anything.

I might try and do something with this in a P-60 module with an XR-E or XP-E eventually, and see if anything good comes about, but I'm not risking 36 XM-Ls.

Oh well, time for shens with a short-arc style retroreflectors
 

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
More stuff in the mail today!
fe90bfa9.jpg


9732f466.jpg


Doesnt fit though :-/ any idea what I should put in it instead? ;) *hint* it'll still be related to this light, and its ordered and shipping right now.

I have a model of the part I'm having machined as the heatsink(in the works now) , but autocad is being a pain, and crashing on opening, so I'll re-install that later and post it up if anyones interested, though its not that much different then the initial renders, just with finalized dimensions.
 

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
Do'h for some reason I had 800px wide in the head, not 800x800. And Ahorton *almost* smashed it out of the park on the first guess.
 
Last edited:

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
More parts in the mail. A package that got next-day shipped from Hong Kong. I opened it and said
J6D7p.jpg


No pics of opening because I tore into it like it was christmas morning, but I did take some pics after it was open.


827b0880.jpg

2 batteries in 2 holders, next to a 1.25D mag

428e221a.jpg

put together the cells, flip the holders over so there is tabs on one side, sockets on the other, and you can put the cell pairs together after you press the cells in. Very nice, I wasnt looking forward to trying to fit 10 cells in all at once.

50e4d01d.jpg

all lined up

b48adfac.jpg

locked together. I had to trim the "feet" on the cell holders, they were too long for the pelican case, so I cut them shorter. They are there to keep conductive things from being able to reach the cell screws. This is going in a plastic case, so no problem.

81f1b0ee.jpg

in the pelican case.


Its gonna be wired into a 10S pack, making it 33v nominal, 36v charging, and the cells are 16AH each, or 528 Watt hour, about the same energy capacity as ~50 2900mAh 18650s (($950 in AW 2900's anyone? :duh2: )) I dont think its going on an airplane with that much lithium in it. (even though they just got shipped here on a plane. :sssh: )


Before I put together a pack fully, I'm going to be testing cells out, making sure they all are good, around the same capacity etc... putting 4 in series and discharging them with the 100W light emitting resistor that came with the thor, charging with either my cellpro multi4, or cellpro 10S and logging the data. And hopefully just enough room in the pelican case for connectors, a battery management circuit, and mounting hardware.
 
Last edited:

TOQ

Newly Enlightened
Joined
Apr 8, 2009
Messages
109
Location
No. California
:takeit::takeit::takeit: When this project is completed I ask you to pack it well in a nice hardcase, box it all up with lots of padding and ship it to me overnight express mail. Don't tell me the price as that means I can't afford it. Send me the bill snail mail via Australia, then reroute thru Nepal, on to Guam, and so on. Hopefully the invoice will eventually arrive yet give me time to cough up enough coin to cover it. If I can't I will send you an IOU with one very small drop of my own blood so you will know I won't cheat you, etc. If this works for you, you can just bet it works for me. GREAT PROJECT, wish I had the talent and knowhow to do something like this as I do have "the host" body just like yours but really don't care much for the light that it currently produces. All the best to you with it, hope to see some beamshots when the finished product makes its first venture out into the dark of night...............

Regards..........Terry
 
Last edited:

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
I see potential.
subtle battery joke? about 36v of potential?

:takeit::takeit::takeit: When this project is completed I ask you to pack it well in a nice hardcase, box it all up with lots of padding and ship it to me overnight express mail. Don't tell me the price as that means I can't afford it. Send me the bill snail mail via Australia, then reroute thru Nepal, on to Guam, and so on. Hopefully the invoice will eventually arrive yet give me time to cough up enough coin to cover it. If I can't I will send you an IOU with one very small drop of my own blood so you will know I won't cheat you, etc. If this works for you, you can just bet it works for me. GREAT PROJECT, wish I had the talent and knowhow to do something like this as I do have "the host" body just like yours but really don't care much for the light that it currently produces. All the best to you with it, hope to see some beamshots when the finished product makes its first venture out into the dark of night...............

Regards..........Terry

Sorry, only looking to trade at the moment, oceanfront property in arizona would be slick.


Charging/discharging 4 batteries at a time to see if they stay fairly even as they discharge etc... So I have a 4S pack hooked upto the original 100W halogen bulb to drain it. Thing just wont die! Been running for 1.2 hours and still at 12.8V!

EDIT: so 4 of those cells in series ran the Thor for ~2 hours and 10-15 minutes, quite a run time. If you get the smaller 10AH version of the cells and you relocated/removed the thor's electronics you could probably fit 4 of them internally on the light.
 
Last edited:

2100

Enlightened
Joined
Apr 4, 2006
Messages
897
Location
SINGAPORE, South East Asia
Also waiting patiently for beamshots. :D

It's cheating, but 10 XM-Ls budget lights can be had for usd140 shipped. 4000 lumens OTF only, so it runs real cool (10 mins makes it barely warm).
 

RCantor

Enlightened
Joined
Mar 11, 2011
Messages
598
Location
KC, MO
What a great project! While we're waiting for updates, 2100, would you PM me aa link to this 10 XM-L light? Thanks.
 

CKOD

Enlightened
Joined
Aug 3, 2010
Messages
708
Ive been busy moving and being without a lab to fiddle, but I'm finally getting PCB etching equipment in order so I can start playing around with stuff. Ive got a plan for everything overall, just working on the battery management before anything else, which is a bit dry and easy to get distracted from.


icH5J.jpg


I got ahold of a nice work bench on the cheap though so everything can be unpacked and there to remind me to play with it. Now I just need more test equipment for it.

Oh and RCantor, forget a 10 XM-L light, look at the kong 12 http://elektrolumens.com/Kong/Kong-12.html

Oh and since the internet loves pictures, I havent been completely idle. I did build a temp PID controller and lighting timer for a pet corn snake I got.

8a4268e7.jpg


But getting test equipment, and getting my PCB etching setup working, are whats coming up next so I can work on the BMS.
 
Last edited:
Top