[Review] Folomov 18650s

On my 18650s, on turbo on a fully-charged cell (even the cell that came with the light), the output would turn blue and dim down to maybe 100 lumens in less than 5 seconds. After further testing I determined that this only happened with some cells. Some older higher resistance ICR cells did not have this problem. I emitter swapped mine to XPL HI and the problem went away. Now it works on any cell with zero tint shift.

Bottom line: yes, the emitter they chose just doesn’t tolerate the current. They should have used a different emitter.

That said, apart from this easily fixed LED issue, I quite like the light. It’s extremely short for a light with a tailcap button and has an unusual tail-cap mounted driver. The UI is ok, but could be better. I don’t like the long-press for off in illumination mode.

This light would be a “must buy” winner if Folomov made a couple simple changes:

  • change the emitter to something that can take the current. XPL or XPL HI work fine.
  • change the UI in non-tactical mode to something like Olight with single-click on-off and shortcuts to moon and max.

Overall I’m impressed with Folomov’s efforts. They’re a relatively new manufacturer, but they’ve come out with a number of innovative original designs recently. The 18650s is an excellent improvement over some of their prior lights, but isn’t quite where it needs to be yet.

I have to say the tint colors are all over the place. As others have said, turbo turns a whitish blue. Every tint below turbo seems ok. Also this thing gets hot fast. I do like the light. I will like it better with an xpl of some sort, just have not decided which emmiter to use yet. May even try an SST-40, once I figure out how to change the LED on this mcpcb.

Changing the emitter isn’t too hard, but is a bit tougher than a standard star.

The bezel is unglued and the star is screwed on. There is just one leadwire to desolder when removing the star.

The star itself contains:

  • The emitter (XP footprint)
  • Two resistors
  • A post on the back of the star that serves as positive contact to the battery.

You can’t just put the star on a hotplate and heat it up. Doing so would cause the post on the back to fall off.

  • I used a small table vise rotated so the jaws were parallel to the table. I used the vice to grip the post, not the star. The star itself sat on the upper edges of the vise’s jaws.
  • I heated up the LED with a hot air reflow station. A soldering iron touched to the edge of the copper star would also work, but would be more difficult as the star would be more likely to move around when the solder melts.
  • Once the solder melted, I used tweezers to remove the old LED and insert a new one.
  • The entire star was loose at this point since the solder holding the post to the LED had also melted. I gently pushed the star back into the correct position using toothpicks and tweezers.
  • Let it cool enough for the solder to solidify and you’re done.
  • SST-40 uses an XML footprint I think. As such, it wouldn’t fit on the stock star. Since the star has resistors on it, modifying an XML star to work in this light would be quite difficult and probably not worth the effort.

If you wanna use a luminus led it’ll have to be an SST-20 (nothing wrong with that choice at all though) as it’s their only XP footprint led.

Personally, unless you need that bit extra throw I like the LH351D > SST-20 but I think most people who have used both would say the opposite (I mentioned it cause it’s another XP footprint option what would fit on the stock mcpcb)

Where can I get a heated air flow station for a reasonable price and do you direct the heat on the top of the LED?

I use this one . I purchased from Amazon.

For the reflow I use the smallest hot air nozzle that came with the unit and have it blowing directly at the LED from close range. Works great.

Would glueing the post in place for the time of soldering make it easier?

Mine failed after 5 months. Contacted Folmov and they are unable to help with replacement parts. Even attempting to send it in for warranty which they did not offer would cost too much. I really like this light for EDC but it will not be replaced because of the unique assembly of this light. In other words if the driver fails like mine did it is not replaceable because it is a part of the tail switch. Guess I can put a regular tail switch in it and just run it at 100% with just an off and on. Something to think about when purchasing this light. Purchase date was 11-27-2018.

There is a group buy in TLF for the Folomov 18650S in a special version:

- military grey body

- Nichia 219D with 5000K

- slightly higher output

- battery with higher capacity (3400mAh) and powerbank-function

  • price: 22,90 including shipping

https://www.taschenlampen-forum.de/threads/groupbuy-folomov-18650s-mit-5000k-nichia-military-grey-3400-akku-powerbank.69699/#post-986309

How did they increase output?

they used a cooler led?

Yes, 5000K instead of 3000K.
Perhaps some more lumens because of cw.

My unit luckily still works, I use it as my bike light (with LH351D 4000K 90CRI) and I really like it like that. So I hope that my driver keeps working :neutral_face:

I love the sound and look of this light, but just not the UI :confused: damn.

(Still looking for ideas for sw45k…)

That’s a bummer. I signed up on their site but, it says I don’t have permission to view that thread. Oh well. I’ll try again tomorrow.

Ah o.k.
Explanation: new members with less than 50 postings don’t have permission for the underforum market place.

I see. Well I will see if I can find one someplace else. I have a few of the original ones. One has a LH351D in it and the other has a SST-20 in it. Mine have been rock solid so far. Would love to have one of the 219D 5000K versions.

I sent you the informations :wink:

Thank you very much.

A convoy deep carry clip fits the 18650S reversed for head up carry, an excellent upgrade because the e-tailswitch activates with light pressure and with the stock (head down only) clip position it was constantly getting bumped on in my pocket, (for me anyway) this has totally resolved the issue.