The lens needs to be a bit further away from rge led when zoomed in, perhaps an extra spacer of some kind where the o-ring under the lens is? You can start with loosening the lens a bit, or with a piece of cardboard to test how thick it should be, and for a permanent solution there might be a rubber washer of the right size in a plumbing store?
Strange. When you get it focused better, I wonder if the darkened parts will still be there. It looks like the emitter might have been damaged on one side, perhaps, or maybe part of the dome is still there on one side.
You could also examine it by putting it on moon mode, pulling the lens most of the way out to focus, and aiming a camera down inside to get a close-up picture of the emitter. You may also need to shine another light down inside, depending on how the camera behaves. I don’t have any zoomies with moon mode, but here’s a pic I got from that method with the light off:
(click to get even closer)
To me it looks like part of the dome is there, its effect could easily be causing those irregularities in the beam pattern (not the ring). Maybe you needed to soak for longer than one hour?
I sometimes take pictures of emitting leds through a cd (also good for looking at the sun during an eclips :-) )
Well, i'm focussed now :).
I have used an extra 'O-ring' of solid copper installation wire to adjust the lens a bit.
The projected picture of the die is not as sharp as my sk68 zoomy.
As you can see in the picture, the beam has a purple imperfection in one corner. Maybe the die is damaged, or its a little bit of the dome left on the die.
Well yes, maybe there’s a little part of the dome left. I don’t think soaking the PCB for a longer period would help, as the dome completely fell off and was kind of ‘crushed’, not dissolved. As the naked die is very vulnerable I didn’t brush the surface.
Well done! The blue in the corner is typical of a chip of phosfor broken off in the corner of the die during the dedome (you should be able to see it in a close up of the led), exposing the blue led underneath.
The image suggests that the led is not exactly centered under the lens.
Cheap glass lenses used in flashlights tend to do worse imaging than plastic ones. I still like them better because they do not scratch over time, and I do not want the ugly die imaged sharp anyway.
I think this is collatoral damage of dedoming then?
:) I'm fine with the picture. Ans the beam is small enough for me now.
or maybe cellulose based thinner is a bit harsh, I mean, full dedome in just an hour or less, that’s pretty fast chemical reaction.
Anyways, all those discolorations and unwanted rings are reason I don’t buy zoom light.
depends remains of silicone or around your LED?
I dedome with thiner and it works very well.
after the ball fell off is just lash out, blowing hard / blow / blow and back for an hour or two in it!
then back hard blow / blow BLOW … and you have a clean dedome.
the harder you drive up the Amp (4 or higher) clearer and more how you obtain whiter light.
furthermore, you can gently with a black marker around the silver plate LED colors around the LED itself to reflection.
The only thing I want with this flashlight is a spill from afar 100m + which is the same as the hub you have to + –10 meters.
if someone trick or another glass knows please replace. please let me know
and of course … of course even more light! :bigsmile:
another beam shot,
this time the modded Uniquefire uf-t20 VS a modded Trustfire X7, emitter : XP G2 R5 2B (with dome) at 5A current .
left: uniquefire , right trustfire
The Trustfire X7 should be at ~225 Klux.
What do you think guys? The uniquefire spot looks more intense, isn`t it ?
Solder paste? In the video it he uses ‘solder paste’ in the pill… I am not sure what this is, can someone send a link to where I buy… Maybe from the ebay?
This is only one of many places
clicky link
Go onto Ebay.au and search for “solder paste -flux”
be careful as there will be a lot of flux under all kinds of names mixed in the results :~
Cheers David
Question, could you scoop a glob of it, put it in a syringe with say a 14ga blunt tip needle (I use rotary tool and diamond wheel to grind sharp tips flat [I use it to put e-juice in my vapor systems thru small screw holes) and use that to place small bits of solder paste on the pads for reflow?
I used the full syringe tube that I got from amazon to dab globs of this on the pads when I made my 32*7135 SRK and 20mm TexasPyro Nanjg driver
A stencil from OSHStencils would DEFINITELY be a good idea if you plan to make more than one at a time (and they do VERY good work, I got both my stencils for the above, haven’t used them yet, but got the plastic mask and stencils for very cheap!
Here is rosin solder flux
https://www.fasttech.com/products/0/10001213/1101900-high-intensity-soldering-flux-paste
But definitely like that FT solder paste! NICE!
I have been using a toothpick, but stencils would be much faster and more precise for quantity work.
Hi,
first thank you to the thread starter for this nice mod and detailed review, I really like this stuff 
Now my UF-T20 have arrived and i really like it. Still waiting for drivers and leds, seem there is no luck there for me…
Borg, liked very much your work too, and I am for xpe mood too. Still one question in my mind, how its possible u have spend all this in torch and leds and so on and still are missing a lux meter? I strongly advise you to get one, it will help you and us a lot.
With my bad luck with mail I have, got a lux meter and still waiting for led and drivers to arrive lol.
ah one more thing I am measuring stock UF-T20 and is giving me around ~ 22Klux, but my batteries are cheap TrustFire. Look that reading ok ?
22klux sounds plausable, that is what you can expect of a xml in a good zoomie.
(thanks for the thanks, I would have never thought that this thread would attract new posts even after a year :-) )
Well I believe this thread will go strong for a lot more than one year
Personally i like throwers, and really like pocketabile ones with just 1x18650. My dream one will be one that is small like an M2 for excample or even a little bit smaller and throw 100Klux and up 
(pretty much impossible by today standards I know)
This T20 is in the upper limit of the size to my tastes, so I will try to experiment a little bit with it with the hope to up the lux numbers as much as i can.