Arc-AAA Led replace???

I want to replace my Arc-AAA Led with a new 26k LED. How do you take the old led out. I know someone mush had done this mod. Can someone point me into the right direction?

Thanks,
Cuong. /ubbthreads/images/graemlins/confused.gif

impossible dont think. Also i believe the Arc AAA is the newest Nichia LED. If you got old version, go get new one.
Also dont think those 26k LED from China get more light output.
P.S. I am Chinese,but i tested it.

From what I have heard of the 26k LEDs and the arc even if you figure out how to replace the LED I wouldn't use a 26k as the arc would probably overdrive it too much thus prematurely dimming may occur. Get one of the new nichias from grumpy's group buy instead as I think they are the same LEDs in the new arcs.

Replace it with Grumpy's Nichia CS LED.

I have seen a couple of threads on How to open A Arc AAA, I currently dont have links though /ubbthreads/images/graemlins/frown.gif

But, It does require some skill, Thermal Cycling and some "un-Crimping"

But Once Done, it will be as good as a Premium...

I have done a couple of these now for myself. I had a couple of PM requests on the process so here is a copy of what I sent:

The longest part of the operation is unpotting the head. It is a little risky as well because you have to heat the head (either hot water or direct heat) to soften the epoxy and then pick off the epoxy in little pieces with a sharp tool. The risky part is to the board components while using a tool like a dental pick to fleck off the epoxy. Depending on your luck/skill/patience there is a chance that the board could get damaged during this part.

1. Remove the foam ring.

2. Carefully uncrimp the head. I used a combination of tools (bull nose cutters, small flat tip screwdriver and a larger pin punch to roll the edge smooth when it was uncrimped enough). Ensure when you are done this part that there will be nothing in the way to prevent the board from coming out.

3. Heat the head and then use a dowel to push on the LED to slide the encapsulated pill out of the head.

4. Dip the pill in a pot of hot water to heat it up. Quickly and carefully pick off the epoxy while the pill is hot. Repeat the heating/picking until all/enough of the epoxy is gone. (This step takes a while because the pill is so small it loses its heat quickly.) You really have to resist the temptation to pick off huge chunks. Also be careful at the top as to not damage the small O-ring around the LED while unpotting.

5. Once the epoxy is gone, unsolder the LED. Be careful not to try not to bend the legs from their formed shape.

6. Bend the legs of the replacement LED to the shape of the one that has been removed and trim for length.

7. The output capacitor will either be soldered to the board or directly on the LED legs. If it is on the LED legs it will have to be resoldered to the new LED.

8. Solder in the new LED. Ensure it is centered. Re-install the LED O-ring.

9. Slide the assembly back in the head.

10. Re-crimp and install a foam battery ring.

I did not re-pot mine because you never know when an even brighter LED will come out and the unpotting stage really sucks. However, if left unpotted, the light will be more susceptible to mechanical shock damage because the potting helps support the components.

Paul

oh yeah someone did it lol ;p
nice work chimo
but yeah it request a LOTS of Skill to work it out /ubbthreads/images/graemlins/tongue.gif

ARC AAA with 26K mcd 5mm is about 2.5 to 3 times brighter. Most important - a pure white beam. The driving current is 30mA which is a bit over the spec. of 20mA. For the beam quality I 'm getting, I wouldn't mind to swap another 26K when it gets dimmed.

You can drive Nichia LED up to 100mA and it will not break. tested even 150mA. I break 4 of them when i am testing those(100~200mA).LOL $2 USD
If you compare T Ranking NSPW500CS vs 22k China made White LED.
then you wont see much difference.I think i will put beam shot later.<--Someone took my DC :/
well i dont think it can reach 2-3.5 times brighter than Nichia.
How many mcd you get with 26k?
Nice Work by the way.
Also do you have more pictures when you replace it?

Thanks

Thanks Thunder. I think that AW was probably comparing output against the original ArcAAA. I had first replaced the NichiaBS LED with a 26K and it was brighter (probably close to double). I since switched to the NichiaCS LED. Not as nice a beam colour but they should last much longer.

AW, I think the ArcAAA current is around 50-60mA. I also found the 26K to be a little dimmer than the NichiaCS.

Paul

chimo,

Yes. I was comparing the 26k against the original ARC AAA. The new NSPW500CS is indeed a little brighter than the 26k. Well, my mistake on the 30mA /ubbthreads/images/graemlins/grinser2.gif

AW

not all ARC AAA heads were potted. seems most of later ARC's were not potted at all.

I've got new uncrimped heads if you destroy the old one. also have dead loaded ARC AAA heads available.

please PM if you need some.

Very tempting....maybe I should try it.

I just did another one last night. That was my third one so my time is improving. /ubbthreads/images/graemlins/smile.gif This one took me about one hour and 15 minutes. I even polished the reflector (put tape around threads, put it in the drill press and used a cloth with some polishing compound).

Measurements (@ 1 meter w/ a new Lithium battery):
Before: 31.1 Lux
After: 54.8 Lux

Paul

cy, would a version 3.x be un-potted? Mine has the side engravging, but it was before the flickering problem ones. I really love my arc but would like it brighter, and not wait/pay 40 for a new premium one...

Chimo: My main concern with taking it apart is that the crip will break off when pushing it back down. Aluminum is brittle and doesn't like to be flexed. Also worry if it will make good electrical contact...

Chimo: How hard is unsoldering the led? I've done DorcyAAA's, and Xnovas, am I going to be ok? Doesn't look like there is much room to get a soldering pencil in there under the led case...

Mine is one with side lettering, but not the "flicker" ones. I'm hoping it's not potted. I'm going to go a head with this. I sure hope I don't destroy my precious and be without it!

Isaac

It's easier to heat the LED legs from the battery side (they protrude through the board but are cut flush with the surface). Heat one leg end while putting a little sideways pressure on the LED and the leg will start to come out. Do the same with the other leg and go back and forth between the two until the LED is free. (Clamp the board so you don't burn your fingers) A very fine tipped soldering iron is almost a must for this.

The unpotting process is the worst part of the operation.

Ah, ok. That should be easy then to unsolder it. Now I gotta get me a new Nichia.. <checks on gb> Thanks.

if removing something you won't use again.. cut the lead first.. than it makes it a whole lot easier to remove such as a resistor or LED not having to fight the 'other lead' when pulling.. no 'rocking back and forth.

-awr

chimo, thanks for the detailed procedure! and AW for the pics.
So the crimp doesn't break like in the Infinity lights? When I operated on my Infinity, I used a micro-thin screw driver, went very slow, and even then, the crimp broke off. Breaking the crimp doesn't really matter ('cuz of the way I set up my mod), but if I'm going to use the Arc board again, I may (?) need to secure the (NEG) contact on the board (right?).

Now, can someone direct me to a source for a brighter LED? I guess I'd go with a Nichia, 'cuz the 26k would die, and I don't really want to do this twice. Thanks!

andrewwynn said:

if removing something you won't use again.. cut the lead first.. than it makes it a whole lot easier to remove such as a resistor or LED not having to fight the 'other lead' when pulling.. no 'rocking back and forth.

-awr

Click to expand...

Good advice. I wanted to keep the BS LEDs (and one turquoise) for later comparison purposes.

Paul