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

This is more or less what the design was inspired by actually. We didn’t want to copy it anymore since convoy is not making it and it would suck to flat out rip off the design.

Plus adding fins only adds weight to an already very heavy head.

Good…… because personally, I think the design looks great!
I hope it does remain basically unchanged…… :+1:

wowowow, it is too much L6 for me as it is :wink:
the L6, blocks at the top and tail, completely different blocks on tube, the anti roll cut outs have nothing to do with any other part. I use it in the dark and am happy I only see the light it produces, the rest I do not really care about.
But that is me, “over smaak valt niet te twisten” or “no point in arguing over preferences” function on the other hand, yes, that is objective (or well should be :wink: ) thus seeing the current render, from top downwards, there is a straight line that goes on where the anti roll fins are. I think that this could and should be done smoother, so less deep fins there, maybe 3 less deep fins with little wider cut outs for anti roll.

crude sketch

We could eliminate the fins in the anti-roll cutouts as well since they are just cosmetic. The anti-roll couts could also be widened and spread out a bit further IMHO. So instead of 8 cutouts, reduce it to say 6.

that “tactical ring” at the tail, would that not suffice as roll prevention?

Is the “tactical ring” going to be removable?

If it was installed it migh, although I figured it would be removable like the S70 / L6.

the issue is that with that much weight and size in the head it could easily overpower the tactical ring if the surface is not perfectly flat.

But then if they are not “lined up” it may not matter and it could roll anyways, so maybe the tactical ring is the best idea.

That would allow the head to follow the contoures of the reflector close by, less material, less weight, and elegant looks right?
maybe just screwing in one of those nuts for thick lanyards in the tripod mount would prevent rolling too.

Same as this preliminary design…
Yet it looks… O well, the L6 is not exactly beautiful design either…

So let’s just stick with the first idea then?
I find that rather strange.

I don’t know about you,but when iḿ looking to buy a light, the exterior matters.
In fact, it’s the only thing you see when browsing, and a light either appeals to you or it doesn’t.
This decides the purchase, except when there’s no other choice and you really need it.

It doesn’t get any prettier with more thinner and deeper fins…
And considering the surface area of the GT, it’s not necessary either.

But hey, we have this decided (correct me if i’m wrong):

8 x 18650
XPH35
120mm reflector.

About anti roll:
I put lights on their heads on a table, not on the side.
None the less, it is better when it can not roll off the table for sure.
But i don’t like the sharp points resting on the table, it should be flatter i.m.o.
Also, every sharp edge will result in anodizing wear.

Look, i just say it would be good to have a couple of designs to choose from rather than stick with the first preliminary ideas.
I don’t know about you guys, but apart from being a portable light source, a flashlight is also a pretty piece of metal that can look really nice, which makes them desirable objects.
But apparently you and TA don’t care too much about the looks, so why not leave this more open for discussion for those who do care.
I mean, i fail to see the reason to stick with this design.
And i’m not gonna push my design (several pages back), but rather i would like to share thoughts about it here and have 5ar look at the options too.

One more thing:
Battery carriers.
WHY??
I can tell you why not though…

Alright, i’ll go see what i can do with my image editer, but things like fins and knurling are hardly possible…

Later,
J.

If they end up doing direct drive (which I don’t think will work very well due to the voltage being too high) it will draw way more than 3A, I haven’t seen any tests done over 3A for the XHP35 so idk what happens.
If they use some current regulation and limit it to 3A, then it will be drawing slightly over 15V

So that’s at least 45W total, and 15% efficiency is a good estimate, so about 35-40W into heat considering 45W is an underestimate.
Also, the hotter the LED gets the lower the efficiency, so without proper cooling the LED could be running at 85C or even more which means less light and more heat.

If somehow they manage to do DD without the LED burning up then it will be using almost 17V and probably like 5+ amps, so a LOT more heat than just the little 3A test from above.

YES!! Thinner and more fins looks awsome!! …and it will cool things down, it’s the way fins work…

I liked that render to the left in post#1212 MUCH MORE than the original…
IMHO :wink:

interested

And I do think that if designated design is cooling things down MORE than it really needs to do, it will be a far better way to go.

If your dragster car cools better in it’s engine…and if you want to change to a bigger turbo, it’s just to do it! And only that….it will be a big advantage it think.
If you “catch my drift” :slight_smile:

More cooling is better for sure but with a light this massive weight is a large factor that has to be considered. You also have to factor in things that normal lights don’t have a big issue with like the likeliness of it rolling off a table ect.

Adding more fins adds more weight, this is something to be carefully balanced.

I personally like fins and the aggressive look. I think the L6 is one of the best looking lights out right now. Others firmly disagree.

Since this is a cosmetic issue it truly is personal preference and comes down to what each person likes.

I can live with a more basic design as long as it doesn’t give up any performance.

That said I truly like the basic layout of the current renders. It looks big and powerful, which is exactly what it is. The fining change and some adjustments to the anti-roll cutouts I have wanted for awhile but it was not worth messing with till we sorted some other things out first.

Being that this is a cosmetic issue, as long as the layout is unchanged, I can really go with whatever is the most popular look for pure aesthetics. Changing to a 26650 or a different tube on the other hand is a performance issue and that is something that needs to be backed up with logical reasons, which I have not seen.

Ok guys so I have done some calculations trying to figure out exactly how the dimensions of the reflector would work.
This isn’t a ray trace and it will not show how one reflector might perform better than another (based on size of LED and distance from LED to reflector curface)
But what it can do is show you how tall or wide you might want your reflector, and the distance from the LED to the closest point on the reflector (making this bigger will reduce corona around the hotspot for a more collimated beam)

Here are the equations you can input to desmos calculator (you can copy paste these right in, one box each):

y=s\cdot x^2-\frac{.25}{s}
y=x\frac{.5}{s}
y=x-\frac{.5}{s}
s=0.03 (for this one you will want to click the number at the end of the slider and set it to 0 <= s <= 0.2 step=0.005)
y=0
–60 < x < 60 (diameter that you want your reflector to be, in this case 120mm) (you can also just do lines like in the image if you want to see better)

Now what you can do is move the S slider back and forth to change the size of the reflector.
You will see that the reflector is sitting slightly below y=0, this is because the LED will be centered at (0,0) and anything below y=0 will not be used at all by the LED, since the LED cannot project light behind it.
Changing S will adjust the shape to be deeper or shallower, and you can see the height of the reflector is from y=0 to the point where the parabola intersects the vertical X lines we put in.


In the screenshot I took, the reflector is 100mm deep, 120mm diameter, and it has almost 34mm opening at the bottom. Green and blue lines are unnecessary but they show that the 45 degree tangent is always on the line y=0, so no matter how big or small your make your reflector it will always be focused at the LED at 0,0. Getting the height is really easy then, since you start at y=0 and measure upwards.


Another way you can use this set of equations is by setting y=the height you want your reflector to be, and adjust S to see the diameter (where the parabola intersects the y line) and that will show you the shpae of the reflector, how much of it is being used, etc. Remember the part of the parabola below y=0 will never be used for reflecting light, so it is just dead space.
Hopefully this helps someone design their own reflector or something :slight_smile:

I must admit, I kinda agree with some on the design. I did wonder why everyone ‘raved’ about it so much, yes the renders quality is very impressive - he/she is very talented, but it’s it basically is an L6, if we add more fins it will be an L6! (or the daddy of, nothing wrong with the L6 design - but this is a bit too similar for me)
I think we got a bit carried away with that ‘quality of render’, rather than discuss what design/features etc are wanted/needed, then making some preliminary sketches (simple line drawings, not renders) - after that , maybe voting on a ‘design’ by one of the guys who are up for it/are good at this sort of thing :) Not go over the top btw, it’s not a competition maybe just choose 3 people to do the ‘design’ challenge, all to the same specs/sizes obviously.
Just an idea.

Oh, and btw I must just re suggest an idea from an earlier post - could we please try to work in another tripod mount hole at the back somewhere? it’s not for a tripod…. it will allow that little cheap adapter (from my post earlier) to screw in an enable many thousands of different shoulder straps (from cameras etc), which would also be very strong.

Most of the issues early on were the design changes were not just cosmetic but functional (such as changing the cell layout). So we could not actually focus on the cosmetic design. I always knew that some revisions would be needed but a lot of them can’t be finalized until we pick a manufacture and reflector so it was no hurry to worry about them before other issues.

I’m to much of a noon…at this point…but is it so hard to find a reflector or a reflector manufacturer how can make wath we need?
I bet Simon at Convoy know…but do we know simon. Maybe he can guide us in the right direction? And if some of you laughing at this post…consider that first sentence one more time. Lol :wink:

And if fins are not needed in the way I thought…the first design is a killer anyway!!
GREAT JOB by 5ar!!! Thumbs up :smiley:

I would like to be added to the list to buy this light. It’s gonna be awesome.