PD68 Review: Thorfire S70 - XHP70 Monster

Basen at 4.18V does 4.12A tail current, Efest 4200mAh at 4.18V does 4.12A. Fresh charged Efest 4200mAh at 4.22V do 4.68A but the same output in the light box at ~3657 lumens, dropping a mere 21 lumens in 30 seconds.

Whereas many of my lights are not practical at all, just more for showing off and making people giggle, I consider this light very practical mainly because of the beam pattern and brightness and battery indicator (with my clear button :zipper_mouth_face: ). It doesn’t get too hot maxed out, but I think somewhere around 7amps would be a better balance of crazy lumens and better battery life. There are diminishing returns at the very high amp levels.

Thanks for “illuminating” the discussion! :wink:

So the hunt is on for the right resistor that fits the bill.

And I envy you for your clear button, mine came with the opaque gray button. :confounded:

I pulled mine back down to 5A for a 4264 lumens start value and 4154 at 30 seconds, balancing the total output with the maintenance of same. :wink:

With 2 R091 resistors on board, I placed an 1ohm on the extra pad, then stacked 3 more 1ohm resistors for a total resistance value of .038494. Stock value was .0455.

I must way, the S70 is used a lot.
We have our chickens and quails under attack.
two dead quails bitten in the neck by a very thin digging predator
(probably something in this family Mustelidae - Wikipedia

last sumer in broad daylight 2 of our chickens were eaten by a fox (we know because we spotted it digging to get into the quail pen later.

So now i check the pens from the house, click clikc and BAM all is lit and I can inspect the whole yard.
Very nice, I do not even have to go outside.

Not surprising, but tailcap amp measurements are all over the place: Thorfire S70 _Tail Amps and Output - Google Sheets

Generalizing the limited information: tailcap amps (stock) run around 4-1/2 amps and OTF lumens (stock) approximately 4K lumens.

My first readings at 3567 with Efest and Basen cells was stock, right out of the box moments after delivery.

I did get it up over 9A and right at 6000 lumens, fall out was horrible, so I backed it down to the 5A setting you have listed second.

I put a 0.2 Ohm on the extra pad and got 6A, it looked like a steady 6A. (using the Basen 4500mAh)
Didn’t test long and when I wanted to test it for a second time I released some magic smoke from the driver… :rage:
Here you can see the 0.2Ohm resistor in place, didn’t know it was a smaller size. (bought it from james @3tronics)

Here you can see that component that released his magic smoke, anyone has an idea what it was?

The rest of the driver seems fine. Could it be from a short at the led? I think the reflector makes contact with the wires, I had some tape on the reflector but it didn’t stay in place.

I didn’t receive my Basen 26650’s yet. I only have 18650’s, MJ1 and standard NCR18650B protected. Which one should I use?

I would use the MJ1”s due to their higher amp rating.
The protected panny”s are very long so not 100% sure they would fit & the protection kicks in not much above the stock S70”s draw 6.70A iirc, would also imagine you would get more voltage sag with them.
I am also awaiting the arrival of a pair of Basen 26650”s to see what tail cap readings they will give with my stock S70 compared to my unprotected 5200 mah Keeppower 26650”s (5.24A) & 5000 mah Thorfire 26650”s (5.01A iirc).
Basen 26650”s have given around 5.5A tail cap readings for some members.

FYI my S70 is totally stock :slight_smile:

HELP!!! new here, not sure how to ask a question. Need help from you tech’s. Got my S70 and it will not come on . Checked in DIY forum and read the info from Don, used paper clip from batteries to body and light comes on and changes modes. So I guess the problem is the tail cap?? THANKS for any help

Mine would not turn on with the ring on. I popped it off and it turned on just fine.

Two things I can think of. First remove the four pedal cigar ring and try again. If it works the cigar ring was not turned all the way down or the retaining ring in the switch was over tightened and not giving you enough clearance. If the second slightly loosen the retaining ring until the light works.

If the cigar ring was not the issue the try tightening down the switches retaining ring.

Just did a tail cap reading with my new Basen 26650”s which I bought after the good reports on here about them & am disappointed.
4.20A compared to 5.24A with my KP”s, 4.94A with my Thorfires & 5.01A with my 18650 Efest 3100 mah IMR”s.
Post about the Basens”s, post 34 & 35 Basen 26650 4500mAh Issue ?

Tail cap readings does say a lot but not everything!
It all depends on the type of driver used.
With a good buck driver, if the cells maintain a higher voltage the amp draw will be less. And the other way around, if the voltage sag is bigger (thus the cells have a lower voltage) the amp draw will be higher.

Let say the the driver regulates the current to 4.5A to the led.
4.5A x 6.5V = 29.5W.
With some driver losses (10%) that is 32.76W from the batteries, or 4.20A with a voltage of 7.8V (3.9V per battery)
The driver wants to maintain that 4.5A to the led, so the batteries has to deliver 32.76W.
I my above calculations I took your reading of the Basen’s, the voltage is a guess but that’s ok since this is just an example.
We know the batteries has to deliver 32.76W to the driver to maintain 4.5A to the led.
Lets take your other reading, 5.24A.
32.76W / 5.24A = 6.25 / 2 = 3.125V (per battery)
So your KP’s voltage does sag a lot more under load so the driver has to pull more amps to compensate that and maintain 4.5A to the led.
(assuming the Amps to the led are all the same)

If the above is true, it means that the Basen’s are very good batteries, even better then the Efest 3100 mah IMR’s

Pls correct me where i’m wrong, this is how I understand the workings of a buck driver.
I could be wrong, but then I wouldn’t know :laughing: .

Could you make a comparison of luxes, with this different batteries? if you do not have a lux meter, you can use your Smartphone with an App of luxometer. It’s not about getting accurate lux values. It is to see the difference between the batteries.

the Driver in the SD75 i reviewed lately does the same…
(8,4 V input vs. 6v LED)

review: Lumintop SD75 - YouTube <- this Link jumps to the driver test

i think you can understand how a buck driver works

What I am disappointed about isn”t the performance of the Basen”s compared to my other 26650 cells but their performance compared to the earlier Basen 26650 cells.
I know that they have less sag compared to say the KP”s but mine are lower resting voltage, lower capacity & give lower tail cap amps than the earlier Basen”s.
Or am I getting this wrong & the fact that these new Basen”s give lower amp readings than the earlier version actually means they are better ?

Could you make a comparison of luxes, with this different batteries? if you do not have a lux meter, you can use your Smartphone with an App of luxometer. It’s not about getting accurate lux values. It is to see the difference between the batteries.