I’m eagerly waiting for your teardown, especially the USB charging section is of particular interest to me since mine failed yesterday.
thanks for doing this
I see. And it can sustain 9K lumen with fan on. So what power off buck driver 
? I’ll say about 100W at max. And another DD channel for turbo? Someone mentioned wants to build 500W driver! I want to see fans for 500W system 
Hi!
Thanks for the post. It got me really interested.
As I searched everywhere, I didn’t see either the official store or any dealer carrying the GT-FC40 option, nor is it listed in any official spec sheet. May I ask where you see that piece of info?
I love High-CRI lights and whether its available in FC40 decides whether I’m gonna buy it or not.
Thank you!
I think loneoceans talk about Acebeam X50 which have Hi Cri version with GT-FC40 LEDs.
Yes, it is particuarly tough on the cells, and most likely any higher power output will yield diminishing gains. But it could be a fun project to try to improve the driver even if it is an impractical endeavour. For example, a multiphase GaN converter would be fun. As for the LEDs, Manker calls it a 'searchlight', though I would definitely not consider the MK38 as a thrower; it's more similar to say the general-purpose SC700d, just a lot brighter.
I'm interested in the USB Charging section as well, and how the 'battery pack' is assembled. Having removable batteries in the 21700-only version seems like a tricky option since the flashlight will be drawing >100W per cell at peak draw, making interconnects and such potentially difficult to implement reliabily.
icpart is correct. At the moment, the Acebeam X50 comes in a high CRI variant. I asked Acebeam directly and they told me that it will be using GT-FC40 LEDs. They're not very efficient, but they do produce a really nice tint as I found in my Lume-X1 KR1 build. On the other hand, the Manker MK38 comes in a throwier variant using Luminous SFT40 LEDs, which supposedly halves the luminous output but doubles the intensity.
Photography Fill Light|AceBeam® Official Store | Flashlights, Tactical Lights
Mankerlight MK38 Satellite (Power by 3x 21700 Batteries) - Mankerlight Official
I have no interest in buying the light itself, but great interest in the engineering and assembly/design aspects of all lights, especially ones like this that aren’t the ordinary basics. Looking forward to following this thread! Thanks for putting in all the time to do this.
I would consider myself lucky, if I was ever able to see or handle one of these lights in person.
Thanks for the thread and future updates.
I look forward to the review! Your photography is beautiful as well!
Can you perhaps give more details on the “Micro-Arc” finish? How is it applied, and what makes it special? According to the site, the black version of the light is HAIII, it would be nice to know what (if any) difference that makes besides the color.
I have the SFT40/3*21700 version of the light coming soon for review, I assume it uses a buck driver as well, I’m very interested to see how the two versions actually compare in terms of specs/runtimes.
oooh I want one of these…
I am excited for updates!
Thanks for your comments. I'm not a metallurgical engineer so I can't comment definitively on the subject, but my general understanding is as follows (w.r.t. the treatment of aluminium / aluminum):
- Untreated - raw aluminium is a reactive element, and quickly forms a natural, hard, and inert oxide layer on the surface in a process known as passivation. This layer is hard but quite thin (several nm thick only) and easily scratched off - in those cases, the oxide layer quickly reforms.
- Anodized - Similar to the natural aluminium oxide layer which forms when AL is exposed to air (containing oxygen), but the layer of oxide is grown using an electric current while immersed in some acidic electrolyte such as sulphuric acid. For Type III anodizations, the layer needs to be thicker than 1mil (25um) (+ a few other specs I won't get into). This thicker oxide layer is harder than the raw aluminium and provides slightly improved wear resistance and desirable aesthetic qualities.
- Micro-Arc Oxidation - takes anodization one step further; the process is similar, but a higher voltage is used compared to anodization. This causes an electrical breakdown through the oxide layer, and causing micro discharges / arcs to form. These arcs (which are plasma) increase the temperature locally, causing a change in the way the oxide grows. If done correctly, the oxide is converted morphologically from regular aluminium oxide to corundum (same compound but crystalline), and therefore has a significant increase in hardness, resistance and durability.
Anyway that's my general understanding of the process and I am definitely not the subject matter expert and I can't comment on how well the MAO process is done.
As to how it results in the actual product, I'm not exactly sure just yet (in terms of durability or toughness); all I can say is that it looks really nice in person and has a very pleasant, smooth but matte finish. I also like the colour (a very light grey) very much.
it also feels a bit different than anodized aluminium. Maybe it is just my mind playing tricks on me, but I had the impression it feels slighter thicker, making sharp edges less sharp. Sure, this could also be done mechanically before anodizing, but I attribute this to the treatment for now.
@loneoceans
do you have a rough ETA for the next step in your teardown?
I’m really interested in the charging circuit.
Definitely one of the coolest and most inspiring designs in recent years. Low CRI 70.2s might be the worst part about it. It begs for a good tint + high cri combo. B35AM anybody?
Still super cool 
I’m an absolute tint-snob for lights which are used close up. So EDC and Headlamp must have a nice tint and high CRI.
For very high output or throw I can live with low CRI, because the main task of these lights is to either reach very far or just be ridiculously bright, which requires the most potent emitters.
Well said and totally agree :+1:
Personally, I would have to agree with Pobel and Glenn7. It's true that the specs definitely sells the flashlight so I don't fault Manker for going with the XHP70.2 LED here. That said, I think it would be nice to see this flashlight with a XHP70.2 4000K CRI90 variant.
I updated the post with more details about the charger and powerbank circuitry; enjoy!
Thank you for digging into this more. I appreciated the battery pack and charging implementation information most specifically.
I’m not surprised there’s a premium on the in built pack, based on the tear down.
I passed during the sale because I wanted to fully understand the light. I regret missing the deal now, but not waiting to be informed before purchase.
Now that I have details, it’s on my want list.
4000K CRI90 sounds nniiccee. I’d definitely get one more if they ever launch it.
However given its Manker, not Emisar or Convoy, I doubt they’d ever do that…
Thanks for the review. I was wondering how the battery pack was constructed to see if it would be possible to build a replacement pack without sending it back to manker, and it looks like it can be.
Thank you!
Was there a o-ring/seal between the end cap and the main body? I could not spot it in your pics, but I am sure it was there.
I’m happy to see the charging board seems to look reasonably well done. I also like that they used a water-protected USB-C slot and a additional flap for dust/debris proofing - I honestly expected they just rely on the flap, happy to see I was wrong.
My MK38 died during it’s 4th charge (something must have shorted on the charger circuit) , the light got very hot (from the bottom up) and the smell of magic smoke was present.
As I sent the light back to be replaced under warranty I did not open the back to have a look inside, although I would very much have liked to find out what exactly failed, and especially why it failed. I really hope it just died because one component failed instead of indefinitely charging the cells to oblivion, because that would not have gone well had I not pulled the cable.
I’m also happy to see that they did not just completely pot everything. While this offers the benefit of mechanical protection it makes a future replacement of the cells impossible. I agree that they could have done some mechanical protection for the bigger elements on the PCB though.
We shall see whether they used a BMS for balancing on the cells. I really hope they did. Even if the cells were well matched to begin with, the chance of drift becomes real in high-drain applications. I really would not like them relying on matched cells in the long run.
Overall I’m still happy with what I am seeing so far. I really appreciate your teardown and the pictures a lot!
Manker is afterall trying to sell flashlights. If there are enough people interested, I'm sure Manker would create such a version. I'd have preferred that over my 5000K version too.
It looks like Manker is trying to do the right things here - yes there is a nice oring seal on the back. One improvement they could make would be adding some o-ring grease. So far all other entry points, ports, screw holes etc all have o-ring seals.
I'm sorry to hear that and I'd be curious to find out what was the cause of the problem. Did you use the included USB-C charger? As I suggested in my post, I'd like to have seen an in-line fuse to the charger section, which I plan to implement on my flashlight.
So far from what I see, it looks fairly reparable. Manker offers a 5 year warranty if the product fails within normal operation, so it would be useful to Maker to design the product to be repairable. Again, I'd like to repeat that Manker states: "DO NOT disassemble or modify this product which can cause damage and will void the warranty.", so I wouldn't recommend anyone disassemble their MK38. In addition, due to the cells inside, any mistake during disassembly could also lead to a short and cause a fire and safety hazard. Proceed at your own understanding of the consequences.
Agreed with that line of thinking; I hope there is some sort of BMS too but I'm not holding out for it. Thanks for your comments Pobel. I'm glad they are at least slightly useful.