3x 3200
Interested in 1 X 3200k please.
If they pot them I’ll be in for at least 2 3200K and 1 5600K. Maybe more (5-10 3200K & 2-3 5600K) depending on my EDC find at the time.
Thanks iamlucky13 for doing the list. We are waiting for slowtechstef and sb to allow you to edit the first post, but sofar an update in the thread itself will do a good job as well!
In the meantime Barry has answered my latest questions/request. I must say that I’m amazed by the speed of communication among BLF, me, Barry, and the Sofirn engineers. With the Q8 project it could take months before a question or request was answered, if at all, now it is a few hours. :+1: for Sofirn and Barry for communication!
The answers:
*based on the discussion here and my Yuji led tests yesterday (to be posted perhaps tonight) I suggested 25mA as the sweetspot for good output together with eternal survival of the led, and the Sofirn engineers had already the same opinion.
*About body colour: Sofirn already “tried Black, Silver, Light Gold. We try making prototype of Red, Purple”. Perhaps a poll after we see the prototypes? (purple :heart_eyes: )
*they are sure the quality of the soldering will be very good.
*they will add springs on both sides of the battery if they can make it short enough.
*about potting the driver: it is something new for Sofirn but they will do it, the engineers need to “discuss about which hardening compound to use, time of hardening, leaking etc.” But they “believe we can handle it”. So if anyone on BLF is really knowledgable about this, perhaps we can help Sofirn with suggestions, or else they need to find out themselves what will do the job best.
*I suggested a tail like the Lumintop Ant (tailstand+lanyard hole+trit hole) and Sofirn will do that tail if we want it.
*I predicted Barry that at some point a discussion would start about a clip, his answer was that no clip was calculated in the costs of the design, just like the E01 it will not have one and it is meant as a keychain light, and “we will clone from Fenix E01 by making some changes”
Sofar the update!
Interested in 1x 3200K.
djozz, many thanks for the update and also a big thanks to iamlucky13 for compiling the names of interested people!
I will only refer here to the things I have an opinion/interest: a) Colour = that’s fine, no blue, but…black, silver and purple may do the trick :sunglasses: ; b) tail = nice, that will be cool to have all those things in 1!
I’m glad that communication is working well on this 
Sofirn has grown in my consideration and is still going up
Thanks again mates 
Interested in 1 x 3200K and 1 x 5600K
That is a nice project :sunglasses:
Many Thanks
Very interesting developments in this thread.
I'm in for at least one of each CCT.
For potting the stuff of choice should be "DOWSIL TC-6011 Thermally Conductive Encapsulant" from Dow Chemical. This stuff is specifically designed for LED Drivers and it is also the stuff that Zebralight uses in their lights (see this thread on CPF).
Would love brass colored anodizing.
Interested in 1x 3.200K. Thanks!
Interested in 1 × 3200K and 1 × 5600K
Thank you
Interested in 2 x 3200K and 2 x 5600K.
Thanks!
Thanks for the information and link.
I understand that what you linked is a silicone based elastic compound, which may well be good for this but it is not what is used in the E01. From what I read on CPF from someone who managed to remove the driver it is a hard epoxy-type stuff.
I can imagine that the hard epoxy stuff is better at resisting mechanical abuse of the flashlight which is what we are after (combined with waterproofness), while thermal conductance is not relevant at this power level.
Can you imagine how funny it is after this project is launched and became a great success? Then Fenix jumps on the bandwagon. They probably think… damn, we had our chance…
Perhaps they can’t :innocent: . Later more about that.
Interested in 1 x 3200k and 1 x 5600k
Interested in 1 × 3200K and 1 × 5600K please.
Sofirn has given (gifted?) us a much better target price than we imagined getting from Fenix.
So forget my initial interest in post #5.
I’m now interested in 1 copy of every body color Sofirn is willing to make. All in 5600K (old eyes).
I agree that thermal conductance is probably not really relevant (although it might, at least in theory, help to increase expected lifetime of the LED if it is driven above spec).
From what I gather a hard epoxy makes everything completely rigid (and potentially brittle), while a firm (yet not hard) potting material allows a minimal amount of flex and absorbs shocks (but admittedly my knowledge about potting material is limited).
The reason why I suggested this stuff is that Zebralight uses it, and I completely trust them in this regard. Sometime back over on CPF somebody asked Zebralight what components they use in their lights and they answered with a list from which it became obvious that they know what they are doing and always choose the best possible components and materials (e.g. Corning Gorilla Glass, MOSFETs from Vishay etc.).
But it is, if we are being honest, not all that relevant which potting material is being used (after all it is a very small light with few components). Any potting is better than no potting.
I don't know which driver IC the E01 uses, but I think it is worth looking into the Prema PR4401 and PR4402. These are tiny LED driver ICs for single battery (0,7-1,9 V) input with an output of 6,5-40 mA (depending on configuration). They only need a single external component, an inductance (although for higher efficiency it is better to add a few components more).
After a quick look at the datasheet I would recommend the PR4402 together with an 10 µH inductance plus extra components (two capacitors and a Schottky diode). According to the datasheet this configuration should give a LED current of about 23 mA.