Nitecore EA8 tear down - Modding will be later and in a different thread.

Flashlight Modding and DIY Parts
16

bad1

I could see it, if the lip inside the body, below the "heat sink" had been thicker, where the "heat sink" actually sat on the shelf. I could also see making the "heat sink" big enough to "really touch" the body at the heat sink's OD, but they didn't score on either one. What their style suggests is that either:

  1. We know nothing about led technology or electricity and there is no real heat produced, so no heat sinking is really needed.
  2. They are counting on the fact that the majority of people using the light will not be using it on Turbo or even High, but they will use it on low or medium and not for any sustained periods of time.
  3. Nitecore does not have a clue.

I would thing that "B" is the real reason for it. I bet that most manufacturers figure on most people using the lower modes and only on shorter times. I can see that to a certain point, but I think it would be better to opt with a thicker heat sink and get it out to the wall of the head/body by making it a tight fit.

They made a thin head with lots of good fins. They also made a thin body. Why? So heat could get out to the open air and also to a person's hand quickly. This alone tells me that they thought it through, but I just don't feel they hit the mark where the "heat sink" comes up to the body, to transfer heat.

No matter what, I just don't think it's a very good method in the EA8.

17

djozz
One thing I noticed in your mods is that you usually use a lot of heat sink mass. Although that buys you time until that mass is 'filled up' with heat, what matters in the end (I think) is a good thermal connection to the shell of the flashlight (which this Nitecore clearly does not have, shame on Nitecore!). So why not leave most of that mass out but just make sure that there is a good metal 'guidance' for the heat to the outside?

The heat sink will probably be thinner than what is shown and it will be tight (press fit) inside the body. It's just like a Maglite D, there is no room to put a heat sink in the head, it has to go in the body tube.

Rufusbduck
Nice pics. I’m curious about the driver switch combination you will use.

So am I.Laughing If it's an XM-L2, then a DrJones driver. If it's an MT-G2, then whatever the gurus tell me will work, as I have no clue. I just know it has to be able to work with the current switch that is in the light (maybe, for now, possibly). LOL

whokilledJR
It actually seems considering how they’ve isolated the heat sink from the body they are trying to stop heat from transferring to the body.

That does sound like a possibility, doesn't it? Wouldn't that be terrible if it was the reason?

MRsDNF
By using the heat sink like they have I assume they can use a thin walled tube instead off solid to make the body. Less machining and waste.

I will show photos of the body. It was a solid tube and mill work was done, just like the SRK is done.

ergotelis
Quick question, is the bezel easily removable?If you remove it, can you have then access to the led only for mod?

The bezel comes off easily and you can remove lens, O-ring and reflector from the top. Changing the led is possible, but it would be hard to solder down in there.

dthrckt
PLASTIC?!

Yep, isn't that a hoot?! I just could not believe why they would not have used an Aluminum one, (other than weight, which was probably why).

18

Wow, so I guess all those cuts and fins in the heads are aesthetics…

Can’t wait to see what comes of this build!

19

Thanks for the tear down, cant wait for the re-build!

Would it be possible to re-flash the 16f616 chip to create a driver with the ramping ui that you prefer?

20

I would enjoy seeing lumens or lux plotted against time on high and turbo for this light (obviously Justin’s is no longer intact)
I wonder what the risk is for LED overheating damage, since the chip is not supposed to get over 150ºC

21

Thank you for the teardown.

This light was on my "buy" list, and now seeing what you show... I will be passing on it.

It's a real disappointment that for all the aesthetics, and marketing, inside the light has such a glaring flaw.

22

Here's a photo of the body tube. I can see why they do not have a shelf in it for the "heat sink". The body was bored for the AA batteries and there wasn't enough meat left to make a shelf. Also, when the final ID was cut for the pill, it was done off center and might have been better if it had been centered.

body1a

23

Seems more hidden flaws are coming out. I was really considering getting one too.

24

If you go to the other forum selfbuilt has done some graphs and the lux/lumens seem to regulate, so it seems the current setup works. The only time there appears to be a reduction in light due to heat is at the very start before the turbo steps down. If it was properly heatsinked there would probably be no need for a step down on turbo mode.

25

Man, that really sucks in a huge way! This might be the first light to have worse heat sinking than a P60. Thanks for being so determined in tearing your new light apart to expose nitecores dirty little secrets so the rest of us can avoid them. Im sure you’ll perform your usual magic and come up with something truly amazing. At least they didnt use blue locktite. In practice, Ive found that red seems to release with less heat/torque.

26

Maybe this will serve until the mod plan comes together . . .

27

It certainly does look like very poorly thought out heatsinking… One thing I can think of to put a good spin on it is that perhaps it is actually well thought out heatsinking and that they have done computer modelling/testing to ensure that that contact area is in fact enough to get heat out. It’s quite a wide circumference so may appear smaller overall than it is.

This is selfbuilt’s runtime graph, and it looks like that there isn’t any output loss over the long period after the heatsink would be saturated. So maybe heatsinking is adequate afterall.

28

That's why I included the suggestion that maybe we just get too worked up over cooling on these lights. I, for one have no means of testing how well a light gets rid of heat, so the way I do them may very well be total overkill. Maybe Nitecore did a bunch of engineering on it, maybe not. Possibly it ended up being the only way they could do it and make the light the way they wanted as far as size and weight, so they accepted what they could do with the design they had. I don't know, I'm not an engineer, just an old guy playing around with lights. It's up to y'all to figure out what is right and wrong and draw your own conclusions from it, as many of you have already and it's good to see the opinions of others.

29

Whatever the engineering intent was behind the light, its still very bold of you to be the one to crack it open. IMO, you took some great risks to your wallet in doing so. Again, THANK YOU for sharing! :bigsmile:

30

I never liked that light because it uses stack of AA batteries but THIS, this is just sad and disappointing and all that from company that was giving as crap here about prices, Nitecore shame on you, I was eyeballing TM26 but after this I wouldn't give a 100 bucks for it...

Thanks for this revealing Old-Lumens, I hope you will repost this on CPF also, people have a right to know what are the paying for...

31

perhaps you can talk pilot into doing a thermal analysis on it, but i would assume even if its adequate as is the lumen sag would be huge, or the circuitry just adds more power to compensate for the poor design

32

why do you think nitecore put all that lock tite on there - they didnt want us to see this!

33

I briefly considered that, but then of course the circuit can’t measure light output itself but only current to the emitter, so it would be practically impossible.

Remember that all the heat from the LED has to get out from the tiny center pad on its base at the first thermal junction, I’m quite sure that the contact area between the heatsink and body is at least as large overall as that… I agree that the design is certainly less than optimal and imo disappointing too, but I really think the only possibility is that heat dissipation is adequate enough to prevent lumen sag at the post-stepdown levels.

I guess it just means that they could’ve driven it harder if they’d made a better job of it.

34

not so impossible, the voltage goes down as the chip gets hotter, and that can be measured and compensated for, also they may have calculated the lumen drop over time and have pre-programmed the driver to ramp up the juice
However both seem to be an over elaborate solution to this problem

35

Thanks Old-Lumens for doing this teardown for us.

I have the EA4 NW and I love it, but I haven't used it yet in anger for any sustained runtime. Now I'm kind of afraid to.

The UI was actually OK for me and I was considering getting the EA8.

No way in hell I'd buy it now!

Regardless of speculation about thermal engineering tests that may or may not have been done by Nitecore, I think your first impression "Simpy put, it sucks" is a pretty good gut reaction from someone who knows a bit about the subject. No need to second guess yourself here.

Otherwise, why on earth would so many manufacturers and modders have put so much work into designing and improving thermal paths over the years. Simply to raise the prices and trick us into thinking we are getting something we need? I don't think so!

This is not what most people would regard as a cheap clone light. I really cannot imagine what is going on with the engineering / marketing / sales team at Nitecore that they would let this "almost great" light go out in a state like that. It's very hard not to conclude that the fact that it was so very difficult to get apart is that they really don't want us seeing what is inside.

My very uneducated guess would be that perhaps the driver has a thermal stepdown protection to compensate for the crappy build in case anyone actually does decide to run it on high for an extended period with decent NiMH cells. But I know nothing of drivers so others may be better equipped to comment based on your detailed photos.

I'm going to reference this thread in another post soon. Hope that's OK