[GB-Feedback] Supbeam K40-l2

LED Flashlights – General Info 18650 Flashlights
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Hey guys!

The K40s are starting to arrive to the members, so please post a mini review here, or links to your review, pics, or just thoughts.

Please just one post per member. You can edit your post as much as you like, or link to another thread.

Enjoy!

Also, please remember to use Alice for all your Supbeam needs! She was very helpful during this group buy, and earned little to nothing for it

alice@supbeam.com

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Video Overview: (might still be processing)

Here’s a TL;DR version:
Came in a snugly fitting box inside a bag of bubble wrap.
Light quality is good, except I’m not impressed with the dings it came with on mine. A little bit of dust and lint was visible as well. There’s also a sharpie mark on the dial arrow. I think it can be cleaned with a dab of alcohol, but I’m not sure why it’s there in the first place.
The head is NOT glued, so anyone can easily access the emitter. It’s lubed, actually. :stuck_out_tongue:
Access to the driver is easy as well, and has two resistors R100 and R082 in parallel.
The dial ring is very smooth with slight friction, and feels better than the TN30/TN31, which has almost no resistance.

I’ll add more to this mini review as I mod the light.

  • The screws that hold down the driver ring has stripped threads. It was slightly difficult to access the driver.
  • I can’t seem to get the driver out. Any ideas?
  • The LED current is 3.445-3.450A. Do not short the driver’s output directly to your DMM, it will deliver >5A (my power supply had a constant current protection, and the K40 was drawing >6A from the input) and you can possibly burn something up.

Woohoo, modding success!

  • Dedomed successfully using Vinh’s hotplate + razor blade method
  • Increased the current to 6.5A. I used the following resistors in parallel: 0.050, 0.050, and 0.082 Ohms. Shorting the the resistor pads gave a ridiculously high (>8A) current.
  • Lapped the PCB to a mirror (sorta) finish.
  • Changed the thermal paste to MX-4. (Overkill)

Now the mini review/first impressions:

The package arrived relatively quickly, considering that they shipped August third (not the promised first), as shown in the postage stamp:

Otherwise, the package arrived in great condition:

Here’s the weight:

The case arrived in a bag of bubble wrap. Although it was thin, I thought it was adequate because the box was a tight fit over the case. However, it wouldn’t have absorbed drops very effectively:

Nice box with the funny logo:

Unboxing:

Contents:

A couple things I was disappointed about:

  • Black sharpie mark on the dial pointer:

    After I removed it with alcohol, I noticed that the printing wasn’t very clear:

    I thought it was funny how they were trying to hide it. Two effort points!
  • There were also two small dings around the fins… can you spot them?

On the bright side, the head wasn’t glued at all. It was actually lubed!

Here’s the XM-L2 emitter on the copper PCB:

Photo of the lubed threads:

Here’s the contact plate. Notice how one of the screws was badly stripped.

But when unscrewed, I could access the driver:

There were two sense resistors in parallel: 0.100 and 0.082 Ohms.
The measured emitter current was 3.445-3.450A.

The beam was pretty nice, I’d say on par with the TN31. It did have some flowers around it, but it wasn’t very noticeable and was expected of from SMO reflectors.

Now that I’ve modded the current to 6.5A and dedomed the LED, I’ll take a few beamshots along the riverside when it gets dark.

Thanks Pulsar for organizing the GB and Alice from Supbeam as well!

@Sirius9: Will do. I haven’t taken many photos during the mod, but I’ll post them here in a few minutes. :slight_smile:

Edit: Here’s the K40 modding thread: Supbeam K40 Mod thread

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:stuck_out_tongue: <- it’s just me, drooling :bigsmile:
more pics of modification pretty please :slight_smile:

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Now I wish I had gotten in on that GB! That’s one sweet light!

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i think it worked out great - my light arrives tomorrow

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This is unreal,
7/31 or 8/01 they posted packages,
8/03 - CN post office registered my package as “Collection”
8/07 - “Departure from outward office of exchange”
8/09 - package accepted at local customs office
now, wish me luck :slight_smile:

7/20 - I ordered JM26, shipped via HK post office
7/28 - package left Hong Kong
and it still didn’t arrive in my country!!!

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after had id several days, i’m about to make beam shot and my k40 behave badly !!

It always blinking like low voltage pulse on every level except lowest and highest setting. It is not the battery, because my battery is fully charged !!

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Rotation of ring is heavily, particularly one hand.
I let in some drops of thin oil, but didn’t help. How to dismount this and lubricate it?

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Hi guy

Happy weekend. :slight_smile: This is Alice from supbeam flashlight. Any interest or questions about our flashlights, please kindly reply me.
Thanks
Alice

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Great review!!!
Thank You for all your time and effort :slight_smile:
Should have mine Monday but no one will be able to sign for it so it looks like Tuesday for me :frowning:

Thanks Alice for the your work on making this happen.
Very happy to have this light very soon.

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:slight_smile: It is my great honor to help everyone.

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Found out only one screw was in place to hold down the PCMCB - just some epoxy used to fill the other hole. Did they run out of screws??

Also, I'm having trouble unscrewing the threaded connection by the mag adjustment ring. On the TN31, this was glued with LockTite. I've been trying the same method of using two BOA strap wrench's and it's not budging - wonder what's going on. Anyone else have trouble opening up that threaded connection?

The bezel came loose pretty easy, so can get access to the emitter/PCMCB but a whole lot easier if I can open up the other threaded connection, and check/lube/oil the mag dial -- it's really stiff, as Kris2 found as well.

Alice: any help on this? Thanx!

Update: Posted a new thread on the tear down here: https://budgetlightforum.com/t/-/20905

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You'll find the answer here: https://budgetlightforum.com/t/-/20905, but basically, it's not easy on mine. I needed the heat gun and strap wrench's, but this was after removing all parts so no risk to the LED or driver.