# Fenix L0P Seoul Conversion Tutorial (w/ Pictures)



## datiLED (Aug 2, 2007)

This pictorial shows how to open a Fenix L0P (L0P SE or L0D Luxeon) flashlight and upgrade it with a Seoul P4 LED. Do not attempt this mod if you are not comfortable with your modding skills, or do not have the proper tools. I will not be held responsible for any damages to your light if you choose to do this modification based upon the information contained herein. Proceed at your own risk. ---This will void your warranty---

The tools and materials necessary for this mod are:

Strap wrenches (I got these from Lowe's)
Large rubber band, cut into two or three pieces
coffee mug warmer (or other method of heating the head of the light)
Fine tipped pliers
Soldering station or iron
Solder
Fenix L0P, L0P SE or L0D (Luxeon) flashlight
Seoul LED (I chose USXOH for this mod)
Thin copper shim 0.015"-0.030"
Arctic Alumina thermal adhesive (AA)


Fenix L0P on left, LiteFlux LF2 Seoul on right.






Remove the head, and heat with the method of your choice. I chose to use a mug warmer. 





Hot! Hot! Hot! Thread the head back onto the body. This is for safety, as we do not want to crush the thin walls of the head. It also makes it easier to hold onto.





Wrap a thick rubber band around the base of the head, in the direction that you will be twisting to remove it. Use a strap wrench over the rubber band, and tighten.





Do the same for the top of the head. Wrap it tightly!





Affix the other strap wrench, and use some muscle.





It is moving... If at any time the head will not yield, put it back apply heat for a few more minutes.





Success. The head is off.





Clean away the epoxy. This light had less than most L0P's.





Remove the reflector. If needed, heat the head first. This L0P did not have any adhesive on the reflector.





Unsolder the leads of the Luxeon LED, and remove it. Dental tools are stainless steel, and solder does not stick. They were feebies from my dentist just for asking.





Gone. Clean the area well, and wipe with alcohol.





Clean as a whistle! Now it is time to work on the reflector.





Measure the reflector depth, and remove 0.015" - 0.030" from the back of the reflector, depending on the thickness of the shim that you use. For this mod, I removed a total of 0.025". Use firm pressure on a fine flat file. Rotate the reflector after each pass. Keep your fingers out of the reflector cup. When it is the correct height, run hot water through the reflector, and blow the water out. Do not wipe the reflector, it will leave streaks.





Prepare the head for the shim. Clean the head and the copper shim with alcohol. Mix AA thermal adhesive and add a small dot in the recess for the led.





Center the copper shim in the recess, and press it into the AA thermal adhesive. Not too hard, though. It must not make contact with the aluminum. 





Test the copper shim for continuity. 





Install the reflector into the head at this point (for centering the Seoul). Cut the lower portion of the leads from the Seoul LED. Use the Luxeon LED as an example.





Mix up some more AA, and center the LED on the shim. Watch for the correct LED polarity!!! The notch in the tab of the LED is the negative. Make sure that the LED is well seated on the copper shim, and that the AA is in a thin layer.





Thread the reflector portion of the head onto the base and check the centering. After a few adjustments, it is perfectly centered. Allow the AA to dry _completely. _





Bend the leads of the LED to touch the copper traces.





Solder the LED to the traces. I like very fine solder for this step. I am using 0.015" Kester solder. The fine solder helps to avoid solder blobs.





Put everything back together.





Modded Fenix L0P on left, LiteFlux LF2 Seoul on right.
Notice the well centered LED in the light on the left. 





Modded Fenix L0P on left, LiteFlux LF2 Seoul on right.





Modded Fenix L0P on left, LiteFlux LF2 Seoul on right. Both lights are using alkaline cells.
LF2 is on high. Not too shabby, huh?





Modded Fenix L0P on left, LiteFlux LF2 Seoul on right. Both lights are using alkaline cells.
LF2 is on high. The L0P has a bit tighter hotspot due to the smooth reflector.





OK, you have seen the pictures, now go for it!

Most of all, have fun.

datiLED


----------



## datiLED (Aug 8, 2007)

The CPF'er that received the light had this to say about it. 



fluke said:


> Hi Derek.
> Arrived today, very impressed big improvement on the Luxeon, very nice tint, nearly as bright as my L0DCE but not as floody :thumbsup: :thumbsup:.
> Thank you very much, this now becomes my EDC on a lanyard with phone and Inka Pen.
> 
> ...


 
So dig that neglected L0P out of the night stand, or drawer in the kitchen and give it a new lease on life. The mod procedure is identical for the L0-Ti, L0P SE and L0D.


----------



## Pumaman (Aug 8, 2007)

just like your other tutorials, great work!


----------



## fluke (Aug 8, 2007)

datiLED said:


> The CPF'er that received the light had this to say about it.
> 
> 
> 
> ...




Yep I am very impressed with it, don't like the PWM flicker of the L0DCE or L0P SE.
So this mod hits the spot, great service, superb communication keeping me informed all the way, and a very good price.

And at the end of it a truly great little light.
Highly recommended.


----------



## datiLED (Sep 8, 2007)

*Fenix L0D-CE Q5 Upgrade*

So you have an L0D CE, and feel the need for a Q5? No problem. Follow the opening procedure of the L0P as outlined above. For this mod, I am using a CREE Q5, WG tint from Endeavour's group buy.

Do not attempt this mod if you are not comfortable with your modding skills, or do not have the proper tools. I will not be held responsible for any damages to your light if you choose to do this modification based upon the information contained herein. Proceed at your own risk. ---This will void your warranty---

After opening the head per the L0P instructions, use a sharp tool to remove the epoxy over the leads of the CREE, and then pry the LED from the heatsink.





Use a suitable tool (needle nose pliers in this cae) to remove as much epoxy from the CREE as possible. It will smoke less when you unsolder the leads.





_Very carefully_ remove the epoxy from the leads themselves. If you snap the lead off inside the head, you are in for a rough ride. I won't even go there, as I am sure that you will be cautious.





LED removed, and the head is ready for a thorough cleaning.





Fine tipped soldering iron, and fine solder. Not pictured is the paste flux to aid with soldering the leads to the edges of the CREE. Note the spotless pedestal for the LED.





Solder the positive lead on first, attaching it to the very edge of the CREE. Watch the polarity of the LED. The CREE is marked with a distinct "+" in the center of the positive side. A small dab of flux will help the solder flow easier. Note: some people find it easier to solder the leads onto the CREE _after _the _LED_ is epoxied into place. I like that procedure for the P2D and the P3D, but not for the L0D CE. Do what you feel comfortable with.





Before using Arctic Alumina or other thermal epoxy to secure the LED in place, test the LED with your continuity meter to be sure that you do not have any solder bridges. If so, correct them now.





OK, I do not have any more pictures, as my wife took the camera out for the evening and I was too impatient to wait. But, it is really straightforward from here.

*Mix a small batch of Arctic Alumina, and wipe a generous amount under the LED, on the seat of the heatsink. Press the LED into place, and seat it well into the AA.

*Thread the reflector onto the head to check the centering of the LED. Make any minor adjustments, if needed. Let the AA cure completely.

*Get out the DMM one more time to check for any short issues. If you are certain that the LED is soldered correctly, drop a battery into the tube, and fire it up for a few seconds. Wipe that big smile off of your face and get back to work. 

*Mix up another batch of AA, and carefully apply it around the base of the LED, and over the exposed leads. Let the AA dry overnight before testing the light again.

*Thread the head back onto the light, tighten securely and enjoy.

The overall gains for the light were 25% on low, 28% on primary, and only 11% on high. 

OK, you have seen the pictures, now go for it!

Most of all, have fun.

datiLED


----------



## fluke (Sep 8, 2007)

*Re: Fenix L0D-CE Q5 Upgrade*



datiLED said:


> OK, you have seen the pictures, now go for it!
> 
> Most of all, have fun.
> 
> datiLED



I Will 

My P3D will be in the post on it's way to you on Monday :thumbsup: :thumbsup:


----------



## gunga (Nov 19, 2007)

Figured I'd bump this thread with a question.

How do you guys all like your modded LOP's *without* adding the shim/filing the reflector.

I'd asked one fellow CPFer about it and would like some more input. How do you like the un-shimmed beam?


----------



## datiLED (Nov 19, 2007)

gunga said:


> Figured I'd bump this thread with a question.
> 
> How do you guys all like your modded LOP's *without* adding the shim/filing the reflector.
> 
> I'd asked one fellow CPFer about it and would like some more input. How do you like the un-shimmed beam?


 
It is very floody, without a defined hotspot. This may be desireable to some people. 

The L0P has such a small reflector, the beam is already floody. I prefer to focus the reflector and raise the emitter.


----------



## fluke (Nov 19, 2007)

I love my L0P.
Perfect for reading my Map Book when the TomTom craps out and decides I need to take a route that is not accessible at 4am.

A powerful hotspot would just be to bright on the page.

I have my Q5ed (Derek -datiLED- Modded) P2DCE that has a hotspot to die for.
That light is better than my Q5ed P3DCE (Derek -datLED- Modded) :twothumbs :twothumbs


----------



## gunga (Aug 26, 2008)

Hi Derek. Just bumping an old (and great thread). I've done quite a few L0P SEs now, love that mod!

Just wanted to ask, did you have to do any clipping or isolation of the cree led? I've heard there is connectivity below the led and the ring perhaps?

Also, why put AA all over the leads after soldering? Also would it work with just thermal paste below the emitter to make future upgrades easier?

I'm going to have to source out some warm white Crees. BTW, did you find it harder to open up the cree Fenixes? My L0P's came open fairly easily without heat but the crees are well glued together. I killed a few strap wrenches opening up a Ti before too...


----------



## kaichu dento (Oct 22, 2008)

Hmmm, I've been wanting to upgrade a couple L0D's and this has me wondering if I dare tackle the task myself.

I don't want to mess up my favorite EDC, plus I'm actually hoping to find someone who can customize the UI, and it would be so nice to be capable of confidently changing out emitters even if I couldn't do the UI myself.


----------



## datiLED (Oct 22, 2008)

kaichu dento said:


> Hmmm, I've been wanting to upgrade a couple L0D's and this has me wondering if I dare tackle the task myself.
> 
> I don't want to mess up my favorite EDC, plus I'm actually hoping to find someone who can customize the UI, and it would be so nice to be capable of confidently changing out emitters even if I couldn't do the UI myself.


 
You will have a very hard time modifying the UI in the L0D. First, the driver board is completely potted in the head, and you will probably destroy it when you try to remove it. Then, you would have to figure out how to access the programming in the IC, and how to alter it. It is not a simple task under the best of circumstances.

Changing the emitter is not that complicated if you follow the tutorial. Be certain that you take a lot of measurements when you are cutting the reflector, and check for continuity on the copper shim and/or LED before the Arctic Alumina dries. Also, pay careful attention to the centering of the LED in the reflector opening. You won't regret it. It is a very worthwhile mod, and the beam is excellent.


----------



## kaichu dento (Oct 22, 2008)

Does "a very hard time" mean that it would be best left to a pro or that it's best left alone? If you're capable of doing it I'd like to talk price about both the UI and/or emitter changes.

Right now I'm carrying a Rebel 80 but also have at least one Q4 I'd be interested in changing out with a Q3 5A, or whatever other led seemed to be the best tint/output wise.


----------



## datiLED (Oct 22, 2008)

kaichu dento said:


> Does "a very hard time" mean that it would be best left to a pro or that it's best left alone? If you're capable of doing it I'd like to talk price about both the UI and/or emitter changes.
> 
> Right now I'm carrying a Rebel 80 but also have at least one Q4 I'd be interested in changing out with a Q3 5A, or whatever other led seemed to be the best tint/output wise.


 
You will want to leave the driver board and UI alone. There may be someone out there who could get the board out and mod it, but it would not be worth it IMO.

I'll PM you about your other questions.

If you have any modding skills at all, you can probably do it yourself. It is very rewarding, and saves some $, too.


----------



## datiLED (Feb 9, 2010)

Restored the pictures by updating my PhotoBucket account.


----------



## paulr (Feb 11, 2010)

Wow, I don't remember this old thread. I still have one of those modded L0P's I bought from you way back. I haven't used it recently but maybe I'll carry it tomorrow. There are times when I just want the simplicity of a small, single level light that's pretty bright, and the Seoul led is still very functional even though newer leds squeeze out a few more lumens. What a great mod! :thumbsup:


----------

