ONLINE! Haikelite HK4S groupbuy - Quad SST20/40 26650/21700 flashlight

I have no connection or profit in this company. But these are the guys I got the 26800 batteries from for only $4.75 each. This section is probably 99% of what we here would be interested in. Some prices are much better than others some not so. I’ve ordered twice from them, once on a Tuesday and shipped the next day. One order on a Saturday shipped the next Monday.
https://alofthobbies.com/power/batteries/lithium-ion-individual-cells.html Their out now.

Great prices, looks like, across the board. 35E's for $4.07? Nice! Just gotta check shipping.

Shame no stock in the big ones though. I'm surprised - don't think I heard of these guys before.

Just checked shipping: real odd. 2 cells is ~$6 (ok) while 4 cells is about $15 (yikes!). Might still be worth it for qty 2 26800's, we'll see. Plus they are shipped from US.

Got the light today after sitting in warehouse jail.

December 21, 2020, 1:44 pm
Departed USPS Regional Facility
LOS ANGELES CA INTERNATIONAL DISTRIBUTION CENTER

December 14, 2020
In Transit to Next Facility

December 10, 2020, 11:51 am
Arrived at USPS Regional Origin Facility
LOS ANGELES CA INTERNATIONAL DISTRIBUTION CENTER

It does take the 26800 battery. Very bright runs off Anduril UI. Fully tightened it will dent the 26800 batteries positive post. Having a raised post it’s a cosmetic dent. Tail must be fully tightened to complete the circuit but the tube to head junction can be left loose with 1-2 turns left to go. Weight is probably perfect, however I tend to like them a little heavier for heat sinking.

Good to hear. Mine was ordered Nov 29th, still no sign of it in the states. The QB26800 is still out of stock at Aloft Hobbies as well.

Got both my Haikelite HK4S 6500k and Astrolux FT02S 6500k 50.2 today, they seams good supplement to Astrolux MF01 Mini and Astrolux FT03. The HK’s hotspot (relative to the Mini) are narrower but the rest are nicely distributed. Not any experience so can’t be more specific. The silver coating seams much better. The sand are of FT02S are also nice.

Got mine today, ordered Nov 29th. Once it hit FedEx on the west coast, it moved fast. It looks great: in brown with SST-40 5000K's, the anodizing matches up well with my brown HK90, maybe slightly darker.

Out of desperation, I ordered one QB26800 battery from the Ali store here, $12 but came to $21 shipped w/taxes. For some reason it's showing $208 in shipping now. They really don't want to sell these things...

The QB26800 should be arriving in a couple days - it's close.

Did some rev engineering and looks like a small FET acts as about 350 mA, so you can run FET+1 firmware. I loaded Anduril 2. Also upgraded the LED wires up to 18 AWG, added a 20 AWG tail spring bypass.. Can pull ~22 amps from a 40T, 6210 lumens @start (TomE lumens), 5480 (maukka cal'd). Measured 51 kcd at 5 meters.

The QB26800 is back w/cheaper shipping to US now at the Ali store, under $4 shipping, qty 1. But Aloft Hobbies still has no stock.

Reduce the height on the brass + contact or it will dent the top of your 26800 cell. The top post on my 26800 got pressed in a few mm’s, just cosmetic.

K, thanks! Will do.

Does this have regulated driver?

No, unfortunately. Just instead of using the old classic 7135 0.35 amp regulator for low modes, it uses a circuit that I think emulates a 7135. Anything above 0.35 amps is PWM'ing a full open FET.

Would you mind to share the compiled .hex?

I've upgraded the Anduril 2 version since, not yet downloaded to my HK4S. I should do that first, make sure it works, then post it to my google drive share. Hope this weekend I can get to it.

I would love to get more into tinkering with anduril (coding-wise). Which cfg did you use to get started for the HK4S?

edit: I think I’m slowly getting the hang of it :smiley: Used the Emisar D4 and added the button-LED. Thanks

Appreciate posting this test results.

I also got the HK4S (4x SST40), and noted it has somewhat low brightness (I don’t have a light integrating device, but I record ceiling bounce lux measurements — I understand this is not accurate, but usually can get a ‘ballpark’ lumens based on comparing my other ceiling bounce lux measurements of similar beam type flashlight), at first my lux measurement would indicate a “guesstimate” lumens of only around 4000 or less lumens on Turbo (this is quite far from the manufacturer “7000” lumens), tailcap current measured was just around 14 Amps. (I didn’t notice ‘flickering’ on Turbo mode though, which may indicate poor contact but…)

I then checked the retaining ring on the head portion of my HK4S — and it appears it is not that tight, so I tightened the retaining ring a bit more. After doing this, I checked tailcap current, and it imporoved — it’s now at around 18+ Amps on Turbo mode, and my ‘guesstimate’ lumens (via ceiling bounce) would be in the ballpark of 5000 lumens or so. (I used a “somewhat-used, but nearly full charged” Samsung 40T and used the longer tailspring option when I did the ceiling bounce lux (guesstimate lumens) measurement.)

Reading that you get 22 Amps tail current (with the improved wires), my guess is that the default installed wire would be limiting the current being used by the HK4S (unfortunately, I’m not skilled in modding/soldering so if it’s not broken, I generally don’t touch it because I may worsen it further…)…

Sorry, been bizy. I started charging the QB26800 in the light but it was going at 0.5 amps starting at about 3.55V, rather slow, so I rigged up some wiring in one of my SkyRC MC3000's, yes - I got two, best charger out there. I soldered up 2 magnets on 18 AWG, kapton taped up a 20350 battery, and added some cut copper sheet to the end of the 18 AWG wires so I could sandwich in the wires at the ends of the 20350 cell. It worked charging at 2.8 amps, but was seeing some strange behavior. The QB26800 acts like a weak or old cell in the MC3000. Not sure if it's the cell or the way I had it wired in the charger. Haven't tried it yet - should do so tonight.

Too much work. Olight magnetic charger charges at 0.75 amps. Bought 3 chargers with 5 batteries and usually just play top off.

Replaced the brass batt+ contact, as recommended:

Original on left, new one sanded down to ~1.7 mm:

It's an excellent fit now.

Really was kind of simple, but I think I got too much resistance somewhere. With the MC3000 set to 4.22V, it only hits 4.20V then drops to 4.19V when removed.

On the triple SST-40 5000K HK4S on the QB26800 at 4.19V (w/20 AWG spring bypass):

  • 20.1 amps (clamp meter at tail)
  • 4560 lumens at start, 4410 at 30 secs
  • 46.8 kcd taken at 5 meters

Measured earlier on a 40T at 4.21V (w/20 AWG spring bypass):

  • 22.3 amps (clamp meter at tail)
  • 5480 lumens at start, 4590 at 30 secs
  • 51 kcd taken at 5 meters

As you can see, the 40T has a huge drop, mostly in the first 15 secs. The big cell has lower readings but much more steadier over the first 30 secs. Pretty much as expected.