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

[RollerBoySE]

@The Miller

@RollerBoySE

Looks aren’t everything.

When looking at the renders I realize, even more than before, that this light, not even sporting a handle, will be VERY diffucult to handle (as opposed to a box design with a handle).

So I’m out, please scratch me from the interest list.

Don’t agree with you, it is all about balance, just tested it out with my 10kg axe, 5kg axe and crate for bottles that has a central handle with 4 and 9 glass bottles filled with water.
The axes hold easier because the arms hangs straighter down the body.
The weight distribution of the 5kg axe (the 10kg is top heavy since their handles are a meter long) make it balance, I can hold it for a long long time en if needed carry it over shoulder, a box is much much harder to keep at eye level.
But we have had this discussion before so no point in repeating it over and over, OP updated and you are replaced on the list.

Balancing definitely helps, but keeping it compact helps even more.
Just imagine controlling a 30cm (1 foot) long pole weiging 1kg (2 pounds) versus a 2 meter long pole of the same weight. The longer pole requires a lot more force and energy to control when swinging around.

Let’s just agree to disagree; no hard feelings from my side, but this project (the way it’s turning out) just isn’t for me.

[Jerommel]

@mdeni

@Jerommel

Here are some cold hard reflector facts illustrated:

Based on what i go by in my images, maybe it should be a little deeper still, because as you can see the actual amount of light that is focussed by the reflector is quite small.
But that’s the case with all regular reflector lights…
The best bit is just spilled…

Lets put a 23mm-35mm floating lens in front of the led. So it will focus the die to infinity. If we can find a lens that has the required focal distance and diameter we can even attach it to the front glass.

You read my mind !
Been thinking about a set up like that for some time.

It will be a form of large TIR optic that forwards most of the light strait forward.

All of it basically

We can calculate which part of the led light is wasted in spill and project that forward. And how big of a diameter lens we can put on a given focal length.

This is very interesting.

[Jerommel]

@RollerBoySE

@The Miller

@RollerBoySE

Looks aren’t everything.

When looking at the renders I realize, even more than before, that this light, not even sporting a handle, will be VERY diffucult to handle (as opposed to a box design with a handle).

So I’m out, please scratch me from the interest list.

Don’t agree with you, it is all about balance, just tested it out with my 10kg axe, 5kg axe and crate for bottles that has a central handle with 4 and 9 glass bottles filled with water.
The axes hold easier because the arms hangs straighter down the body.
The weight distribution of the 5kg axe (the 10kg is top heavy since their handles are a meter long) make it balance, I can hold it for a long long time en if needed carry it over shoulder, a box is much much harder to keep at eye level.
But we have had this discussion before so no point in repeating it over and over, OP updated and you are replaced on the list.

Balancing definitely helps, but keeping it compact helps even more.
Just imagine controlling a 30cm (1 foot) long pole weiging 1kg (2 pounds) versus a 2 meter long pole of the same weight. The longer pole requires a lot more force and energy to control when swinging around.

Let’s just agree to disagree; no hard feelings from my side, but this project (the way it’s turning out) just isn’t for me.

Meh, it’s only 30cm long.
It’s a one footer.

[Nicolaas]

@RollerBoySE

@The Miller

@RollerBoySE

Looks aren’t everything.

When looking at the renders I realize, even more than before, that this light, not even sporting a handle, will be VERY diffucult to handle (as opposed to a box design with a handle).

So I’m out, please scratch me from the interest list.

Don’t agree with you, it is all about balance, just tested it out with my 10kg axe, 5kg axe and crate for bottles that has a central handle with 4 and 9 glass bottles filled with water.
The axes hold easier because the arms hangs straighter down the body.
The weight distribution of the 5kg axe (the 10kg is top heavy since their handles are a meter long) make it balance, I can hold it for a long long time en if needed carry it over shoulder, a box is much much harder to keep at eye level.
But we have had this discussion before so no point in repeating it over and over, OP updated and you are replaced on the list.

Balancing definitely helps, but keeping it compact helps even more.
*Just imagine controlling a 30cm (1 foot) long pole weiging 1kg (2 pounds) versus a 2 meter long pole of the same weight. The longer pole requires a lot more force and energy to control when swinging around.
*
Let’s just agree to disagree; no hard feelings from my side, but this project (the way it’s turning out) just isn’t for me.

Sooo, basically you want a 1Mcd+ thrower, to illuminate objects at very large distances, and you also want to be able to flick it around in an instant? Really? Why?

Grtz
Nico

[Nicolaas]

@Jerommel

@mdeni

@Jerommel

Here are some cold hard reflector facts illustrated:

Based on what i go by in my images, maybe it should be a little deeper still, because as you can see the actual amount of light that is focussed by the reflector is quite small.
But that’s the case with all regular reflector lights…
The best bit is just spilled…

Lets put a 23mm-35mm floating lens in front of the led. So it will focus the die to infinity. If we can find a lens that has the required focal distance and diameter we can even attach it to the front glass.

You read my mind !
Been thinking about a set up like that for some time.

It will be a form of large TIR optic that forwards most of the light strait forward.

All of it basically

We can calculate which part of the led light is wasted in spill and project that forward. And how big of a diameter lens we can put on a given focal length.

This is very interesting.

.
.
.
Really guys, I mean really?

We have decided to gor for a 120 mm reflector hundreds of posts ago, and now we opt for a pre-collimating lens and a aespheric lens or a hughe TIR optic?
Don’t you think this will make the flashlight “a litte bit” more expensive and, with a TIR lens that big, quite a bit more heavy or (if plastic) more prone to lens-scratches?

It does sound very interesting, but please keep the basics of this project in scope: low cost, easy to manufacture etc………in other words doable.,

But hey, maybe next BLF thrower project can be a massive pre-collimating + aespheric torch? 2Mcd perhaps?

Grtz
Nico

[Jerommel]

@Jerommel

@thijsco19

@Jerommel

This explains a lot:

The blue parabola is the accurate shape, it starts at the bottom with a 45° angle.
But this explains the difference in basic shape of our designs.
I use the blue one. It’s also a little deeper and has a brim on the big end.

That’s why he said:
“I do not know which version is better but there is no need at this point to think about it because while I do not know the dimensions and shape of the reflector can not tell whether this look to stay because everything depends on the reflector. Small changes in the details affect the overall look, will be smarter when we know the details of the reflector.”

A parabolic reflector has a given shape and proportions.
The one he uses to design a light around is way off.
The LED is not in the focal point, he’s using an incan light reflector model.
Iḿ sorry, but just look at the picture.
Do you think i should not have pointed this out?
And as i said, it does explain the different basic shapes between his and my designs.

So the good thing this implies is that we would likely meet with our ideas in the end.
So there.

[thijsco19]

@Jerommel

A reflector has a given shape and proportions.
The one he uses to design alight around way off.
The LED is not in the focal point, he’s using an incan light reflector model.
Sorry, but just look at the picture.
Do you think i should not have pointed this out?

No, you’ve made a good point.
But he already knew it, and so he put a disclaimer in his post saying exactly what you mean.
Though, if he would tweak his design to suit the reflector it would only be some minor tweaks. So not a big deal imo at this point (which is all about outside design)

Alright, I’ve redraw my design so I could run a thermal simulation. Here is the result:

As I said, I’m not sure how accurate it is since this is the first time I did this. However i think this give us a good representation about how it will perform.
This is with a 40watt load distributed along the led shelf. Imaging that the MCPCB will evenly distribute the entire 40 watt load on the shelf.
Thermal convection coefficient is 20W/ (m^2.k), I really dont know what that means but its a good number for natural air convection. (like walking around outside I guess)
Ambient temperature is 300 kelvin around 30 degrees celcius.
I’ve run another simulation with a convection coefficient of 50W/ (m^2.k) and that gives a 20 degrees celcius difference (cooler).

[Jerommel]

@Nicolaas

Really guys, I mean really?

Yes, really.
But not for this project.
Could be a great mod though.

[RollerBoySE]

@Nicolaas

Sooo, basically you want a 1Mcd+ thrower, to illuminate objects at very large distances, and you also want to be able to flick it around in an instant? Really? Why?

Grtz
Nico

It was just an example to help with realizing that size matters.
Small adjustments of something well balanced won’t be too hard, but keeping the length down helps quite a bit over time.

[Jerommel]

@thijsco19

@Jerommel

A reflector has a given shape and proportions.
The one he uses to design alight around way off.
The LED is not in the focal point, he’s using an incan light reflector model.
Sorry, but just look at the picture.
Do you think i should not have pointed this out?

No, you’ve made a good point.

I’m glad we agree.

But

Forget the buts.

[TheOnlyDocc]

@thijsco19

And this simulation confirms what i was saying a few sites before.

Building PC heatsinks and watercooler for more than 10 years (as an hobby) is helping a lot when you try to figure out if a thermal design will work.

[mdeni]

@Nicolaas

@Jerommel

@mdeni

@Jerommel

Here are some cold hard reflector facts illustrated:

Based on what i go by in my images, maybe it should be a little deeper still, because as you can see the actual amount of light that is focussed by the reflector is quite small.
But that’s the case with all regular reflector lights…
The best bit is just spilled…

Lets put a 23mm-35mm floating lens in front of the led. So it will focus the die to infinity. If we can find a lens that has the required focal distance and diameter we can even attach it to the front glass.

You read my mind !
Been thinking about a set up like that for some time.

It will be a form of large TIR optic that forwards most of the light strait forward.

All of it basically

We can calculate which part of the led light is wasted in spill and project that forward. And how big of a diameter lens we can put on a given focal length.

This is very interesting.

.
.
.
Really guys, I mean really?

We have decided to gor for a 120 mm reflector hundreds of posts ago, and now we opt for a pre-collimating lens and a aespheric lens or a hughe TIR optic?
Don’t you think this will make the flashlight “a litte bit” more expensive and, with a TIR lens that big, quite a bit more heavy or (if plastic) more prone to lens-scratches?

It does sound very interesting, but please keep the basics of this project in scope: low cost, easy to manufacture etc………in other words doable.,

But hey, maybe next BLF thrower project can be a massive pre-collimating + aespheric torch? 2Mcd perhaps?

Grtz
Nico

We are still going with the 120mm reflector. No precolimations.

In this 120mm light we can add a small lens, to focus the spill forward, and gain a significant percent of the light towards the corona.

Just throwing some relevant performance ideas out there. Instead of discussing 20 pages for 3 fins or a notch.

[Jerommel]

@mdeni

Just throwing some relevant performance ideas out there. Instead of discussing 20 pages for 3 fins or a notch.

If you want performance i would say recoil reflector set up.
Problem though, is finding a decent and affordable 5 inch reflector that can take at least 120° from the LED.

[The_Miller]

No lenses, but if you show us how to make it float I am sure we are all very impressed and Penn and Teller might want to know it too

Just kidding, lenses are for another project not the GT.

[Nicolaas]

@The Miller

No lenses, but if you show us how to make it float I am sure we are all very impressed and Penn and Teller might want to know it too

Just kidding, lenses are for another project not the GT.

.
.
.
Penn and Teller.

[mrheosuper]

K.I.S.S (keep it simple stupid)
especially when we are making a BUDGET flashlight, i don’t want a cheap Chinese len, the quality is very poor

[teacher]

When popcorn alone just won’t cut it… add a soft drink of your choice. :+1:

[thijsco19]

- YouTube

- YouTube

[teacher]

Thanks thijsco19, that is informative not to mention just downright cool. :+1:

[Texas_Ace]

So basically it looks like from the thermal simulations that the current design is just enough to keep an XHP35 cool enough to not burn you. Anything more and it will get too hot and need to step down. So we for sure need to keep cooling in mind as night time temps here in Texas can be easily 90f+ which would allow it to get even hotter.

Good info!

As far as the reflector goes, 5AR has not had a design to work with since we do not know what we will be using yet. That said I really like the shape he has come up with anyways, the strong taper to the head just doesn’t do it for me, looks a bit silly IMO.

There will naturally be some redesigns once we find a reflector.