The BLF GT70 "Giggle Monster" is here! 7,500lumens, 1,500m throw! Group buy Closed!

I got about half the output number as turbo at the top of the ramp and it ran like so. The sag may have been part heat, part cells to attirbute to the decline in output over the 10 minutes.

I left it untouched pointing at the ceiling in a 22Ā°C air conditioned room with a fan oscilating 2m away. I checked the temp 3 times and it never got hot to the point I was worried about it. I just wanted to go light some trees up from my balcony which are a few hundred metres away (~300m)


Turbo would have got much hotter, sagged much faster and definitely would not have got to 10 minutes in-hand-use in warmer climates like Australia most of the year as it would just be too hot to hold.

EDIT: I forgot to mention the jumps in output is another light source being picked up by the phone too if anyone is wondering why the light increased for a little while. That was when I came back into the room to check temp and stuff around. Iā€™m not sure why it started to climb after the last spike up until I stopped loggingā€¦

Good info nitebiker.

You are correct that the top of the ramp is about 50-60% of the output as turbo and it is set that way for various reasons. One of which is that at this level it can sustain the output for an extended time, where you are correct, turbo will indeed trigger thermal protection in a few minutes and have a much more drastic drop in lumens. That is why turbo is only for limited bursts.

I can confirm this.
I did another ceilingbounce test and
top of the ramp was: ~ 4000-4500lm
turbo was: ~ 8500-9000lm

having a long time sustainable top level is a good choice! :+1:

Thanks KJ for the lumen output testā€¦ blf gt70 can run 6000 lumen pretty long.

Got the Mail - Firefox does not work but IE worked .
Yesterday i ordered three times one CW conversion kit and two carriers .
Now its time to wait ā€¦ā€¦.
Thank You guys ā€¦ā€¦. M.

I ordered this today. (Lumintop GT70 Conversion Kit XHP70.2 LED NW+1*Centering Ring+1*TA Driver Giggle Monster)
I hope it has the right color. (NW)
Many thanks to the friendly users, in this flashlights forum. :+1:

Got a question about heat. Where is the threshold where the heat might damage the components? I know that when something is too hot to hold is above 50C. Does that temperature already represents a threat to the components? LEDs and drivers?
After seeing some videos about reflowing LEDs I can assume they can stand much higher temps than my hand is comfortable with.

No 50C presents no problem at all to components.

Hmm. At what temperature should I start worrying?

Hmmmā€¦ technically Iā€™m not sure. Let someone else answer that one who knows for sure.
I let a Convoy S2+ with an 8 chip driver go one time for about 45 minutes on High. When I discovered/remembered it the thing was so hot I could not touch it barehanded without getting burned (which I did) before I grabbed a towel & shut it off.

It cooled off and continued to work fine. I do not know how hot it wasā€¦. BUT IT WAS HOT :wink:

I tested this light with a fully charged set of 8 30Q cells and disabled thermal protection. It peaked at 90C in a very hot garage.

This is fine for the components, they are generally rated for 125c or more and are not usually damaged until at least 150c.

Now the cells are the bigger issue, most cells max temp is around ~75c+, although the cells will obviously not be as hot as the head, when I pulled them out they were only around 50-60c IIRC.

Small correction - each cell carrier is 4S. Running three carriers would be 3P.

Like Newlumen said, you will need a coupler. The good news is that because of the GTā€™s cell carrier design, the battery tube doesnā€™t need to be conductive, so your coupler could be 3D printed if necessary.

Worrying about what? Donā€™t worry at all. You can set your light to step down at 40Ā°C if you want. Or 35Ā°C.

The driver components can withstand 230Ā°C for a short time. This is when the solder becomes liquid.

Batteries can operate at 60Ā°C to 70Ā°C.

Itā€™s the led that tends to get the hottest. I think it needs to stay below 150Ā°C at itā€™s junction between the led and the mcpcb.

Woah thatā€™s impressive. Im glad to know that my hand will melt before any harm comes to my babiesā€¦ lol.

So let me get this straight. All these flashlights that have a thermal stepdown protection, they stepdown to protect my hands? Not the light itself?

I run blf gt70 turbo mode for 10 minutesā€¦ itā€™s get warm to medium hotā€¦ what a great heatsinkā€¦ no sign of step down according from my eyes.

IDK, maybe yes? If you get burned you might sue the company. They donā€™t want that or the bad reputation of burning people.

It all depends on the light as well. Small 16340 lights that do 900 lumen can probably burn up the led due to the lack of surface area to dissipate heat. The led is always hotter than the outer surface. Iā€™ve heard of lights getting so hot that the solder under the LED would get soft and then a sideways bump would knock the LED right off of the mcpcb.

So having a thermal stepdown is always good for high powered lights. Itā€™s still not mandatory, though. My L6 is over 130 watts (17.6A) and it doesnā€™t even have a thermal stepdown (old Narsil verion). I turn it down when I feel itā€™s hot enough, so no big deal.

For most of them, yes, that is correct.

Holy crap 130w. Maybe I will get close in mine. Just ordered a driver from Lexel,although heā€™s still playing catch-up with his orders. IDK when he will be able to ship it to me.

Ordered the NW conversion kit.