No… I don’t think so.

Just put INR 30Q inside for testing purposes.

At really high powers I get worse performance than others on my led tests too, and I’m thinking that one possible reason is a slightly thicker solder layer than others. I use no solder stencil, and when after melting of the solder I push on the led a slight bit of solder (by no means thick blobs) can be squeezed out so I do not use the absolute minimum.

I don’t know what to say? I always used a little bit more solder paste on XP-G2 S4 2B put I pushed excess off so it got those solder blobs on the side like in pics… Performance of last XP-G2 series of emitters I got from Hank is very consistent too. But since XP-G2 gets naturally sucked in it is really no problem to push excess solder off.

About reflow… I do slightly modified Old Lumens method.
Hakko 936, Largest round flat Hakko tip, and 320 celzius temperature on soldering iron.
Tip is dry(I am not using any solder on it) and I just put it below mcpcb which is held by vise (that small Proxxon vise which has that rubber protection for vise clamps so heat can’t be transferred from XP board to metal clamps of vise, all heat is concentrated in XP board for fast reflow…
Cheap mechanic solder paste but the model with needle application and thin hollow needle( in fact it is very hard to squeeze it through needle, bodybuilder skills needed for that lol :slight_smile: )
5-10 second and it is done.

For white flat I really use thin application. When it reflows I gently move White Flat with toothpick (spreading solder, and centering).

Stencil would be nice… I saw it here:

But this is also not bad although I got to admit that stencil above looks thinner and more pro:

I use slightly more solder on the center pad but nothing excessive IMO.

Thanks. Will do. Been waiting for clear atmospheric conditions. I just read your post about tuning to highest readings at longer distances. That makes alot of sense. Will have to try that.

Did I told you that with L4P boards I have greater gain with FET driver than with Noctigon or Maxtoch board?

I will give you true figures. You know that I use XPG2S42BDD exclusively so following are real figures I was getting before I got L4P board, and I will admit that after I received new L4P boards I contacted L4P and told him that his L4P board looks like crab when I compare it to Noctigon(you know thickness, gold plated etc.), and that I am bit disappointed and then when I tested his L4P DTP I just felt ashamed cause it killed noc and maxtoch in performance. :person_facepalming:

MaxtochDTP - the fattest one used for SupwildfireMitko model :slight_smile: DTP= 4.2A (well sometimes 4.3)
Noctigon DTP= 4.4A current draw
L4P DTP = 4.7A current draw

So here is one more reason why we may getting different results.

L4P even explained why such differences among DTP may occur but I can’t find that post.

You guys have way too many variables to get any useful information.
A constant current buck regulated power supply is necessary for a proper comparison.

Of course you are correct but I can’t really help the variables because I was not testing a led but making a flashlight. :slight_smile:

We will see how this led works out for other hosts and other people. I have not done my last mod with it for sure. :partying_face:

Hmm… That will not be 100% reliable method. Why?

You can still mess something up. So I would say your test is ok but there will variables too…

Proper test should include 3 emitters with 3 different re flow methods:

- solder paste(thin or thick appliance),

- lead less solder,

  • stencil thin solder paste appliance,

And then there are more like reflowing time and temperature (shorter re flow time means better in my diy book cause emitter can loose properties if you are cooking it to long).

And then when you mentioned buck regulated power supply. Is there budget or pro versions of this and possible differences between them which could influence on final test results?

Freaking variables :slight_smile:

djozz, are you going to do an output test of the 2mm^2 white flat? I bought 4 from mouser and can do an estimated output vs current measurement, though luminarium’s numbers give a rough idea of where the peak is. I will also put it in an EE X6 head and measure the throw while powered by a constant current supply.

For me the real advantage is the very low Vf. I plan to put 4 of these in my C8 quad. A single cell will drive them pretty nicely I think.

Exactly, making a flashlight is completely different from trying to make accurate and repeatable scientific tests.
Totally possible that in your scenario some other LED performs better in that case.

D1S or Jaxman Z1 for this led ?
all look good;

Thanks for offering doing the test but I wanted to find out myself too now.

Reflowed a new led on a 16mm L4P DTP board, using enough but sparse solder paste, clamped it well and flat onto the test mount with bit of AS5 in between, and this is what I got:

So in my emitter test set-up I find the led peaking lower at 7.5A, and not at 10A as l.i. found. It may be my reflow, it may be the amount or type of my solder paste (same chinese 63/37 solder paste that many use), I don’t know.

Regardless, even in my test this led puts more light out than the XP-G2 S4 2B (the led from the test is not even dedomed, substract 10% output for after dedome), with a maximum output of over 1500 djozzlumen (probably about 1400 real lumen), which because of the low voltage can actually be reached in a single li-ion flashlight (unlike the XP-G2 S4 2B, that you will not get over 4.5-5A).

I do not know why I did not get better performance in my mini-GT, even though I thought that I had done the mod well, but as said before: so many variables…

(I always treat my emitters very well)

I think Vinh announce his newest mod and pick 3.4v for 1mm2 and 3.3v for 2mm2, your graph match that perfectly.

EDIT looks like Vinh might have got the numbers from led4power because they are totally same.

You said and the graph says KW CSLNM1.TG but that has perfect squaare die. But on the led image it is not square. Is something mixed up?

His graph has both the CSLNM1.TG and the CSLPM1.TG.
One is square die and the other is not.
The most recent test he is talking about right now is the CSLPM1.TG which has a rectangular die.

It is too early morning for me! Need a coffee!


Thanks for the test!
That’s a somewhat dissapointing result in terms of brightness! The low Vf is great. It might just be that you tested a low performing sample.
The Q8WP that koef3 tested a while ago got up to 9.6A (although his cooling setup might be slightly better).

Yes, I get consistent lower thermal performance than other led-testers, if it is the reflow and/or the amount of cooling from my copper mount I do not exactly know. I could order a mounted led from l4p (he uses a different solder) and see if that tests different but I was planning a sort of half test-retirement anyway in which I mainly test for my own builds (and post the test for others to get at least an impression), and the results that I get are certainly relevant for myself.