Potting helps with robustness, but not just in the way mentioned here. Small components will probably never break off. If mixed with suitable materials it can help keep the driver components cool. This is not important at these low power levels though.
The most important thing to fixate would be the wires going to the LED. They are usually the first thing that rips off on impact.I would also contact the battery with springs on both sides. That increases robustness and the light doesnāt turn off momentarily when it falls down. The design of the Thrunite Ti (I own the v2) is very bad in this regard. The didnāt use a real spring in the head, the contact piece they use can break after little useage.
I disagree, I think size is very important, it is one of the key features of the E01 that it is that small. And apparantly a light this small can be very robust without having those thick walls.
That said, I fear that I sound very dismissive in my recent posts and I may have too strong ideas about how this light should be.
On these small lights with no lens the LED is exposed to the elements, my fenix EO1 worst torture test for it is, the potting may help with waterpoofing becausr it has suvived 3 trips through our clothes washer.
Also I want to say thanks djozz for your effort in making this closer to being a finished product.
I can help with the list, as well. Maybe there should be a team account so a single list can be maintained?
Iām very happy to hear theyāre confident they can achieve similar performance to the E01 driver.
I mentioned the possibility of a 30 mA drive current as a suggestion to discuss, but Iām reluctant to push Sofirn to make design decisions theyāre not confident in, especially since weāre only talking about going from ~8 lumens to ~11 lumens. Others also had a good point that the goal here is a bulletproof light, so we want to be certain over-driving does not compromise that.
To clarify something, Yuji specifies the output of the 5600K version as 6.6 to 8 lumens, and the 3200K version as 6.1 to 7.5 lumens at 20 mA. The output curve in their datasheet indicates 30mA should produce just over 1.4 times the standard rated output.
Just my opinion . Maybe I should put it differently. It will not be a dealbreaker for me if itās a bit bigger than the E01. But I for instance still like the old kd buckle v6, so maybe I am not the best reference.
ReyLights are custom orders from Lumintop, I think they use a 500 minimum order quantity.
Massdrop also does custom orders from Lumintop, and I also contacted them to ask about doing a Fenix E01 w Yuji. I have had no reply from Massdrop.
The Massdrop formula is like Kickstarter, first they get a bunch of people to pledge, then they get the money, then they pay the manufacturer, so no risk for Massdrop. If not enough people sign up, no money changes hands.
Good job @djozz for finding Sofirn is willing to do the Yuji cockroach idea. There should be no worry about PWM, as it is not used in single mode lights. How much money does Sofirn want to start production, what is their minimum order quantity, and who is going to pay for that?
as far as momentary on, all twisty lights have that feature/bug, due to slop in the threads, so if you only barely twist off, the light will turn on in pocket from side pressureā¦ I do not care for the āfeatureā, so I turn off half a turn.
Sofirn already was wanting to make an AAA twisty, though perhaps not one with a 5mm straw led, so our request was welcomed and they ask no money for development. In fact they are happy with our input.
fantastic!
as far as potting, though I agree it may not be necessary, it is important to be able to say Yes, this light is fully potted, just like an HDS (or a Fenix)ā¦!
I donāt know how useful this information will be, but yes I have some experience.
A Sunwayman R01A I had swapped a Yuji into died after a couple ~5 foot drops.
I opened it up again to troubleshoot. Everything is so small it was hard to tell for certain what went wrong, but I spotted a diode that appeared not to have been soldered well, and lifted slightly off its solder pad. I presume it was due to the circuit board flexing when the battery hammered against it. Aside from inertial protection, good potting could potentially also help minimize this flexing, but I believe even more important is a good assembly technique to ensure the solder joints are good to begin with.
I added a little more solder, and it worked again after re-assembling, although it still has occasional issues.
Hereās a macro photo I took of it. Thatās a 0.7mm pencil lead in the upper corner for scale.
The inductor is still intact, although I donāt think this was a particularly hard hit. Iām not free of concern that in a harder hit, it might experience high enough Gās to pull loose.
I am in favor of recommending a potted driver based on the known ruggedness of the E01, but the way it see, if Sofirn is producing this light at their own risk instead of collaborating with BLF on a known quantity, itās ultimately their call. Iāll buy several either way.
By the way, the Sunwayman drove the Yuji at 23mA, and the output was very appropriate to this size light.
No, it really is not. He says he wants āexperiences from small flashlight usersā and is completely ignoring all of that experience. There have been lots of destruction tests of inexpensive 1xAAA keychain lights. Skepticism in the face of evidence is not rational.
I agree the issue is the battery hammering against the board, causing broken solder joints
another light that is notorious for failing when dropped is the AA Illumination Supply L11c, and its twisty sibling L10. There is also an AAA version, the L08, though I could not find any reports of people dropping it, I suspect it has similar vulnerability
another possible advantage of potting, is it stops water from coming into the E01 around the 5mm LED, since there is no lens
other AAA lights known for durability, and they are potted, is the Arc AAA and the Peak Eiger
imo, when cloning an E01, it is very important to also clone the potting
note the lack of potting is one of the frequent objections to the Vinh E01, it may be just psychological, but it matters to buyers
btw, I think it is essential for the tail to have a keyring attachment point, I like it on the side of the tail, so the light can still tailstand.
It really canāt cost that much to stuff some glue in the head, and it certainly wonāt do any harm (as long as the correct compound is used). Since the goal of this project is to make the most bomb proof light possible, thereās no real argument to not pot the light.
If Sofirn is unwilling or unable to pot the light and still wants to product it thatās their call, but I donāt see the point of arguing over whether or not added reinforcement is a good thing, regardless of whether you think it necessary. I know, for myself, if Sofirn is making the light and not potting it, I will probably opt to hold off on any orders until I can see some abuse testing.
If Sofirn can make a sampe, potted or unpotted, it would be great to see it run through a stress test side by side with the E01 this project was originally looking for - if the Sofirn light lasts longer or as long, case closed.
I was just ignoring strong language without reference, like āsolder is weakā and ā1000G is rather a lotā , ālegendaryā and āmany testsā . And since I did not know examples myself I asked BLF for actual events happening, and now all sorts of detailed stories are seeping in and now my skepticism is being replaced by evidence in my face . Sounds rational to me.
. Maybe I should put it differently. It will not be a dealbreaker for me if itās a bit bigger than the E01. But I for instance still like the old kd buckle v6, so maybe I am not the best reference.
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