[PART 1] Official BLF GT Group Buy thread. Group buy officially closed! Lights shipping.

Not a suggestion, but merely stating that the TR-J20 has extremely thick battery tube walls, and still houses 32650’s. It’s a beefy light, for sure, and I’m sure they were leaning towards heavier, not lighter, in all discussion when designing it.

When I did the extension for Richard, he sent the battery tube and tail cap for me to work with. I saw this tube and knew I had to have the light, promptly ordered my own based purely on how solidly the battery tube was made. lol

Okay then! Ditch the 26650 idea! Even lower cost and problems.

2х2 18650 8mm thinner tube. Plastic insert, cheap aluminium tube. No problems with carriers and connections.

But remember, 4x18650 is already very thin tube for the 13cm head. We do not want to make it like this:

There is just way too much fuss about the cells and battery tube. Texas_Ace and The Miller are not Tony Stark with unlimited resources. We should focus on making it simple. Otherwise it will kill the project. I suggest everyone be happy that you can be a part of this awesome project, but unless you come up with a revolutionary groundbreaking idea, please let the team enjoy this unpaid work and make it easier, not harder for them.

I think that was the point of the latest suggestions.

Didn’t know that, dont have a SRK like flashlight here to know how it feels.
So what about the little smaller side by side setup?
The only problem that I see is that the balance might not be optimal.

+1

Didn’t know that, dont have a SRK like flashlight here to know how it feels.
So what about the little smaller side by side setup?
The only problem that I see is that the balance might not be optimal.

How would you make the connection?
If you have one cell with the anode to the driver and the other with the cathode to the driver you’ll need separate contact areas on the driver contact side. (and maybe a spring?)
But if you turn the tailcap on the tube there is a possibility that they dont line up anymore, also increasing the possibility of making a short. Which you dont want with a 4s setup.
By using a carrier, which could be made out of plastic, with an contact board on one end that has 2 contact rings you dont have that problem.
Or am I missing something?

(weird, was editing my post but apparently I made a new one…)

I totally agree, a light such as this has zero appeal to me visually.
I know it is not supposed to be about looks, but I just can’t help it; lights like this just looks goofy to me. :blush: . :person_facepalming:
But hey, that is just my opinion…. (pretty shallow & petty one at that > :person_facepalming: < ) ; but it is what it is. :smiley:

Tony Stark works at Wuben right :wink:
Nothing wrong with brainstorming IMHO when something is decided it should be a real group thing.
This is what makes this GT so early already (and the Q8 as well) so cool of a project!

Indeed the last few ideas have actually been things that could be used, if it was deemed necessary.

Although before we try to change things, I am still at a loss for what is wrong with the 4/8x 18650 tube? What doesn’t it do that these other ideas would?

Basically, what is better about the latest round of ideas? All I see is the inability to use 8X cells if someone so desired. Why not simply only run 4 cells in the 8 cell tube?

acutally I Like this idea, 2s2p should be using, so that we can have either using 18650 or 26550, or both
2s 18650 is able to drive xhp 35

To me the 4/8x 18650 tube makes the most sense, period.
In addition, as far as I am concerned; it would be ridiculous to “change things” or even think about “changing things” unless the questions Texas_Ace asked above are answered in a ‘reasonable’ way that would appeal to the masses.

2S will not drive a XHP35 without a boost driver. We need 4S, this is non-negotiable since we can not afford a boost driver for the goal budget.

+1 :+1:

Cheers David

All the ideas are meant to reduce cost of the light, and keep it simpler. If it can be made with the carriers for a low price than that is fine of course. They seem pricey and complicated to the casual observer.

Well, 4/8x 18650 design compared to new 4x18650 design.

4/8x tube:
Advantage: more runtime with 8 cells.
Disadvantage: more total weight (if used with 8cells), thicker.

4x tube:
Advantage: smaller, less total weight (compared to 8 cell setup)
Disadvantage: not being able to run it with 8 cells thus having less runtime (compared to 8 cell setup).

What doesn’t change:
Runtime when 8 cell tube is used with only 4 cells.
Weight when 8 cell tube is used with only 4 cells. (oke, weight is reduced slightly)

Personally, I dont care, just throwing out ideas. :smiling_imp: :beer:

How can I get into this buy?

Why not?!
This is a nice “Bimmelglocke”: Der Bimmelglocken-Thread | Taschenlampen Forum

Two 4 series carriers makes the most sense.

For me, personally, I don’t see why we don’t just have a dedicated 8 cells. It’s a search light, it’s gonna need run time to be used as it’s designed. There are perfectly adequate cells available for very cheap monies, no more than $40 for 8 really good high capacity cells can be found easily. This would have the absolute maximum effects, delivering BRP without a hiccup. (Balance, Runtime, Power). I bought the extension set for the TK61, ran 8 cells, didn’t have a problem with it. That was a much higher current light and it worked out fine.

As a comparison factor, the battery tube with proprietary cells for the TN42 is about $70, for the proprietary battery pack alone (4 cells)

While I do like the IDEA of everyone contributing on the making of a light from the ground up, I’ve seen repeatedly where it’s not sound business practice. A team should get together, decide the parameters, have the light made, then offer it for sale. To me that ensures optimization, without long delays in argument while ideas get tossed around like a beach volleyball. I’ve seen the open thread idea hold up multiple lights and even kill off a couple entirely. Seems funny that people are willing to get upset because they didn’t get what they wanted, but Nitecore, Fenix, Surefire, MagLite, Thrunite, Solarforce, EagTac, ArmyTek, SupFire, Olight, 4Sevens…. they build what they want and offer the lights for sale, they don’t take stinking polls! And most of us here have those brands, never had a single bit of input on how they built the light.

Diversity can build strength and character, it can also break the core, polluting the purity of the concept. Field of Dreams said it , “if you build it, they will come…”

If you build it right, they will come in droves!

Absorbing a lot of heat is right but only until the material is thermaly saturated then only the surface will help dissipating the heat.

Making the finns smaler (~1,8-2,2mm thick and a bit higher ~10mm) would help. The distance between the finns should be ~2,5-3mm.
Making them even smaler would help with the heat but they would be to fragile. Not something you would want on your high quality flashlight.

And the further you get away from the led less heat will be dissipating. So the finns can get smaller and smaller. So that the head will not get bigger.

To abandon the finns on the GT is not wise (or to use the 5-6mm thick only 5-6mm high finns that you can see on the prototype picture). They look good but will not help much with the heat.
Here a small example:

on the left i have a 10*10cm alu plate. Put a LED on one side and use the back for heat dissipating. You get a surface amount of 100cm². On the right side i put only 5 10mm high finns on the plate. Now you got 200cm² of heat dissipating surface. If you increase the amount of finns to 10 the surface area increase to 300cm².
Now do that on your flashlight base where most of the heat is generated. And you will increase the surface amount by 100-300% and you will be prepared for new more powerfull LED´s.