*BLF LT1 Lantern Project) (updated Nov,17,2020)

Interested depending on final price, will be watching this thread.

XP-L 7A3 80 CRI is a nice led for a lantern, I have one of those in my brass CQG 18650 especially for camping.

The 7A3 is my favorite natural warm white tint for lantern use because of its near incandescent light. Its the least glarey of tints i have tested, and gives a candle-like glow on moonlight mode. (there are warmer tints available, but they seem to go to yellow)
my other favorite tint for Lantern use is the XM-L-V3 5D. its a 4000K neutral white with a very slight redish hue, much more pleasing to the eyes than the other 4K tints that have a greening hue.

Other honorable mentions for lantern tints go the 7A4, 8B4, 4C, & 3D (3D being the coolest tint i would ever put in a lantern)

More progress updates on the BLF Lantern project in the lower part of the OP on the first page! now with first Beamshot test photos indoors! / April,3,2016

- and still running on maximum mode. (6.5 hours and counting) I will have to shut it off soon as i can’t stay awake all night to monitor its run time progress. (then restart it tomorrow evening)

I am discovering however the constant running temperature of the XP-L 7A3 on the head at maximum mode has been holding at a constant 44.3 degrees Celsius for the last 6 hours. (running at a constant average of 1.1 amps measured with the three-7135 QLite driver.) ( See IMAGE below:)

- This temperature to an adult hand feels very wrm, ( borderline hot) but if a child touches it may feel to hot) this confirms that with the XP-L it is at its peak running amps versus efficiency for this application, ( remember the head of the lantern is a heavy solid block of aluminum, much bigger than most single 18650 flashlights could ever have) so if a modded driver of higher amperage is used an additional heatsink may be required.
But in this prototype lantern its a good balance of output vs. amps draw vs. heat dissipation for lantern use.

Got to love a GB!

Count me in!

Im getting excited about this project. I love that you will be doing real world testing. I like the faux mantle diffuser.

This is shaping up to be the best led lantern.

really like this idea. IMHO the driver will be interesting - needs firefly/moonlight and multiple other low modes, for long life, and one longish bright mode and something(s) in between. Might be a good candidate for an electronic switch with ramping up and down……

depending on price, I’m in for at least a couple……

I am using a driver already with Moonlight/firefly mode. (the Q-lite Rev. of the Nanjq 105c has those modes with 4th star jumped) though in a lantern for moon light it could be a bit lower. ( maybe a custom firmware reprogrammed. I avoided any electronic switches because of several reasons, it reduces modability for the lantern with other drivers, and will add a parasitic drain. ( bad idea for long term storage with cells in it unless the body is unscrewed every time to lock it out. ramping up & down is not ideal either, as its near impossible to determine run times like stepped-mode drivers. any lanterns i have that had ramping i got rid of the ramping modes with new driver swaps.

You make a good point about parasitic drain. Less sure about your run-time argument against ramping, as it’s likely to be used over a few nights and many wouldn’t remember how long it had previously been used for, so run times will be somewhat unknown anyway.

I guess my point was that having a lot of flexibility at the low end is critical for this sort of application, whereas at the high output end, there’s less need for such a range of options. Very low is critical, very high less so. Simple to use is also important, as it’s likely to be a ‘family’ lantern….

Have you considered adding some deep cooling fins in the top piece? This would have two benefits. It would remove weight from the top making it more stable when its set down, and it would increase the passive cooling when left on high for long periods.

good point, the fins could be machined in top edge. i will add that to the drawing blueprint design.

I’m certainly interested. I have a few lanterns but they pretty much all suck.

Good idea.
I am interested.

I am interested too.
Thanks for sharing us!

In a good momentary button driver the standby current can be a few uA, way below self discharge. 10 uA would theoretically take 100 years to deplete 4*2200 mAh.

Also you could try applying d-c-fix diffuser film.

Also some kind of battery indicator would be nice.

Maybe consider XM-L2 for its lower voltage, it’ll stay in regulation longer.

Very true, 10uA is almost nearly an open circuit compared to some momentary-on factory flashlights. You would be the good candidate to program or design a driver design for this that incorporates a battery-level function, which would be a great feature.
Right now it has a XP-L 7A3, but do have a XM-L 7A2 3200K that will go in the lantern soon for more tests & photos.

It would be nice to have a lantern that wasn’t terrible. I’m interested.

How would this compare to the Fenix CL30R? Uses 3 18650s, 5hrs+ at 600 lumens.

Is there a rough estimate of the output/runtime of this lantern?

I am in.