BLF recoil über-thrower

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djozz
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My blue laser is this one from Banggood, bought it for no valid reason at all, and I’m pretty scared switching it on, even with green glasses that absorb almost all of it. It is actually even 2.5W.

Still not sure about doing the experiment Sad

http://www.banggood.com/445nm-2_5W-2500mW-Blue-Laser-Module-With-Heatsin...

Enderman
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djozz wrote:
My blue laser is this one from Banggood, bought it for no valid reason at all, and I'm pretty scared switching it on, even with green glasses that absorb almost all of it. It is actually even 2.5W. Still not sure about doing the experiment Sad

Bah, it's 2.5 chinese watts, so probably more like 1-2W Silly

Just shine it at some old LED you don't care about burning and see if it makes more, similar, or less light than the LED driven regularly.

This isn't going to damage your eyesight as long as you don't shine the laser onto your eye or on a reflective piece of metal, I wouldn't be that worried.

 

EDIT- actually I did more research and found this: http://jss.ecsdl.org/content/5/10/R172.full#ref-15

4000lm+ with a single crystal phosphor, which doesn't get damaged by laser light, can withstand up to 300 degrees C, and has a high thermal conductivity for cooling.

Problem is that the laser needs to be over 14W to get that much output.

This definitely seems like a possibility for a flashlight, I will keep looking and maybe buy a YAG:Ce crystal if I can find one, and then maybe a high power laser.

I think 4000lm+ in a few mm size would be decent intensity for a spotlight, I can definitely see this replacing short arc lamps in the future Smile

Anyway, enough derailing the thread, let's see what OP can do with a regular LED and that mirascope reflector Big Smile

Lexel
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There are 4.5W diodes availiable
Its probably driven by multiple 2W laser diodes

Jerommel
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Enderman wrote:

EDIT- actually I did more research and found this: http://jss.ecsdl.org/content/5/10/R172.full#ref-15


4000lm+ with a single crystal phosphor, which doesn’t get damaged by laser light, can withstand up to 300 degrees C, and has a high thermal conductivity for cooling.


Problem is that the laser needs to be over 14W to get that much output.

Wow! 4000lm from 14 Watts power is better then any LED ?!
(edit) Ah, that’s 14 Watts laser light output power…

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

luminarium iaculator
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I needed to repair friends Ultrafire UF-007 recently(burned emitter swap) and I can say that even swapping old burned XRE EZ1000 to new XRE (old and unused) was a pain. And as you know XRE has nice bottom +- contacts so It can be handled easier than most emitters. Modding with XP-G2 or similar will require more thinking and tinkering (so to reflow to miniature pcb and epoxy it or reflow same configuration to minature brass shim or even direct reflow of bare emitter to miniature brass shim)

My opinion about estimated performance even before you finish it in comparison with 50mm aspheric:

UF-007 is 25kcd light if you manage to get 1.8A to stock XRE.
Good 50 mm aspheric with same XRE emitter will roughly have 70kcd at same drive current.

Modding: Swapp old XRE with de domed XP G2 de domed and better components in 50 mm aspheric and you are roughly at 220kcd which is around 200% kcd performance increase over old XRE so it is right to estimate that with same modding of UF-007 light you’ll also get 200% increase and that means that even modded UF-007 will not pass 100 kcd.
More likely around 80kcd.

It will be nice experiment… Good luck Thumbs Up

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luminarium iaculator wrote:
I needed to repair friends Ultrafire UF-007 recently(burned emitter swap) and I can say that even swapping old burned XRE EZ1000 to new XRE (old and unused) was a pain.
Yeah, it’s soldered to the tiny copper core of the centre piece of the boom. I used a tiny butane torch to heat it up and pulled the XR-E off by the wires.
Quote:
And as you know XRE has nice bottom +- contacts so It can be handled easier than most emitters. Modding with XP-G2 or similar will require more thinking and tinkering (so to reflow to miniature pcb and epoxy it or reflow same configuration to minature brass shim or even direct reflow of bare emitter to miniature brass shim)
Does it need a shim for the correct focal distance?
Quote:

My opinion about estimated performance even before you finish it in comparison with 50mm aspheric:

UF-007 is 25kcd light if you manage to get 1.8A to stock XRE.
Good 50 mm aspheric with same XRE emitter will roughly have 70kcd at same drive current.

Modding: Swapp old XRE with de domed XP G2 de domed and better components in 50 mm aspheric and you are roughly at 220kcd which is around 200% kcd performance increase over old XRE so it is right to estimate that with same modding of UF-007 light you’ll also get 200% increase and that means that even modded UF-007 will not pass 100 kcd.
More likely around 80kcd.

It will be nice experiment… Good luck Thumbs Up

I took my UF-008 (same set up as 007) apart, removed the XR-E and will (try to) give it a new slim copper boom and planning to use a de-domed XP-E2, run it on 5× 7135 if possible (heat dissipation).
I expect it to be comparable with a 35mm aspheric lens.
It will have a tighter beam than one with an XP-G2.

For the 6” recoil light i’ll use a XP-L HI initially.
I’m thinking about a way to make it zoomable by moving the LED towards the reflector, but this will obviously complicate things..

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

Jerommel
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Dang, i just measured the UF 007 (or 008) and it approximately reflects about 90° of the light, which is more than i expected.
With the mirascope reflector the light will only reflect an additional 30° (120°) which is only 33% more… Sad
That’s not so über i.m.o…

Maybe use a tiny primary lens…

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

djozz
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Using extra optics will not increase the throw, even decrease it a bit. It may increase the output and hotspot size.

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djozz wrote:
Using extra optics will not increase the throw, even decrease it a bit. It may increase the output and hotspot size.

Yeah, i know, but since it’s such a big reflector, maybe a good compromise can be achieved with a little bit of pre-collimation…

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

leaftye
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Nicolaas wrote:
Even if you guys could find a suitable host and reflector, won’t the placement of the led with big limitations on heat transfer limit the Amps the led will be able to endure?

I would think so. If I ever try this, I want to use liquid cooling to help get heat out of that pillar.

The low mode should be lower.

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luminarium iaculator
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Does it need a shim for the correct focal distance?

Well I think that maybe it is not necessary… How? Once you put those tiny copper bolt out and re-flow emitter directly to it
(this will be tricky and pain since you’ll need to trim those tiny bolt before pre-tining and soldering directly to bare led).

If properly done you can manually adjust height to desired level (probably around 0,7mm higher from copper bolt base) and mark an outline on that copper(brass) piece when you find correct distance.

After that put it back in a empty bolt hole glued with thermal glue like artic alumina.

About long tiny wires… Anything larger than 24 awg will be to much and you could braid it and epoxy once when done.

Choice of XP-E2? Well I am not sure… That will be to tiny but good thing is maximum performance at very low current draw. I think it reaches full performance around 2.2 but Djozz knows that better.

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Jerommel
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leaftye wrote:
Nicolaas wrote:
Even if you guys could find a suitable host and reflector, won’t the placement of the led with big limitations on heat transfer limit the Amps the led will be able to endure?

I would think so. If I ever try this, I want to use liquid cooling to help get heat out of that pillar.

I’m considering it too actually.
Just hope 2 heat pipes will be enough, otherwise you need a waterpump too…
We’ll see. Smile

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

Enderman
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Jerommel wrote:
Wow! 4000lm from 14 Watts power is better then any LED ?! (edit) Ah, that's 14 Watts laser light output power...

Haha yeah, lasers that powerful are like $500 USD, even I can't afford that just for a potential experiment.

Maybe if I can find someone at my university with one...

 

 

Jerommel wrote:
Dang, i just measured the UF 007 (or 008) and it approximately reflects about 90° of the light, which is more than i expected. With the mirascope reflector the light will only reflect an additional 30° (120°) which is only 33% more... Sad That's not so über i.m.o... Maybe use a tiny primary lens...

Yes but the reflector is very small, which means the LED is a short distance from the reflector.

The closer the LED is to the reflector, the more beam divergence you will get due to the LED size.

If you made that reflector twice the size, the focal length would double, the LED would be twice as far away from the lens, and the beam divergence would be reduced even more.

This would be a similar effect as using an LED that is half as large (die area)

 

So yeah, the mirascope reflector should still be a huge improvement. Smile

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If you’re going to use heat pipes I’d suggest using a perpendicular head (think zebralight) for ease of manufacture. The laser design seems very effective but kinda dumb. Who wants to put on protective glasses every time he wants to use a flashlight? High power lasers can cause permanent severe damage to eyesight in a fraction of a second. To me that’s a big “Fuck No” as far as using them when not absolutely necessary goes.

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bikedude wrote:
If you're going to use heat pipes I'd suggest using a perpendicular head (think zebralight) for ease of manufacture. The laser design seems very effective but kinda dumb. Who wants to put on protective glasses every time he wants to use a flashlight? High power lasers can cause permanent severe damage to eyesight in a fraction of a second. To me that's a big "Fuck No" as far as using them when not absolutely necessary goes.

 

The laser idea was just a concept for future stuff I might do, OP isn't actually going to do that for this light.

The point of laser+phosphor crystal is to get something similar to a HID searchlight but without needing several-kilovolt power supplies and thousands of watts of power.

HID lamps are also dangerous because they emit UV, can explode, contain toxic gases, require thousands of volts to run, etc... but people still use them because it is the only way of getting light powerful enough to reach many kilometres.

There will always be some risk when dealing with lights like this, which people are willing to take to make the brightest light possible, or in this case use a new technology such as laser+crystal.

This is not meant to be a typical flashlight that you just use to light up a path or anything like that. It isn't even called a flashlight at this point.

Image result for 5000w sky searchlight

Jerommel
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bikedude wrote:
If you’re going to use heat pipes I’d suggest using a perpendicular head (think zebralight) for ease of manufacture.
I need a 6 inch alu tube section, maybe a 19” alu strip bent around in a circle.
On it i will have to somehow fix the heat pipes which will be the boom that holds the LED.
Is that what you meant?
Quote:
The laser design seems very effective but kinda dumb.
I thought it was a very nice idea actually, but unaffordable and as you say:
Quote:
Who wants to put on protective glasses every time he wants to use a flashlight? High power lasers can cause permanent severe damage to eyesight in a fraction of a second. To me that’s a big “Fu*n*k No” as far as using them when not absolutely necessary goes.

It’s not gonna be a laser exited phosphor. Smile

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

Jerommel
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Enderman wrote:

Jerommel wrote:
Wow! 4000lm from 14 Watts power is better then any LED ?! (edit) Ah, that’s 14 Watts laser light output power…

Haha yeah, lasers that powerful are like $500 USD, even I can’t afford that just for a potential experiment.


Maybe if I can find someone at my university with one…


 


 


Jerommel wrote:
Dang, i just measured the UF 007 (or 008) and it approximately reflects about 90° of the light, which is more than i expected. With the mirascope reflector the light will only reflect an additional 30° (120°) which is only 33% more… Sad That’s not so über i.m.o… Maybe use a tiny primary lens…

Yes but the reflector is very small, which means the LED is a short distance from the reflector.


The closer the LED is to the reflector, the more beam divergence you will get due to the LED size.


If you made that reflector twice the size, the focal length would double, the LED would be twice as far away from the lens, and the beam divergence would be reduced even more.


This would be a similar effect as using an LED that is half as large (die area)


 


So yeah, the mirascope reflector should still be a huge improvement. Smile

Of course, but my initial goal was to reflect as much light as possible and out throwing everything else with the same ‘light engine’ and hotspot size.
Now i’m not so sure if this will be better than a multi lens set up (with which i have gotten some impressive (at least to me) results)..
We’ll see.
Soon the mirascope will arrive, then i can get an idea.

..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

Enderman
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Jerommel wrote:
Of course, but my initial goal was to reflect as much light as possible and out throwing everything else with the same 'light engine' and hotspot size. Now i'm not so sure if this will be better than a multi lens set up (with which i have gotten some impressive (at least to me) results).. We'll see. Soon the mirascope will arrive, then i can get an idea.

 

Recoil is definitely the best way to get almost all the light, I have a flashlight using a 100mm aspheric which has awesome throw and 1M lux, but there is over 50% light wasted even with a Wavien collar, so it's about 500lm or less actually coming out the front.

I'm not a fan of multi-lens setups due to the inefficiency at each lens, and imperfections/error gets multiplied every time making the collimation worse. 1 or 2 lenses is the optimal configuration. or a single reflector.

Currently I'm doing some tests with an aspheric+spherical lens, I got about 1 960 000 lux on the last test (no collar) which is pretty impressive, although the thing is as big as a garbage can and weighs like 5kg xD

 

I'm looking forward to seeing your reflector results, if you can get at least 500k lux I will also buy one Big Smile

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If heat is a concern, what if the arm was (at least in part) a heatpipe as opposed to solid metal?

leaftye
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It could be drilled. I’m talking about pumped fluid, not a liquid salt. Other options are good, I’m thinking aloud about how to use these fancy mills.

The low mode should be lower.

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Cythras wrote:
If heat is a concern, what if the arm was (at least in part) a heatpipe as opposed to solid metal?

leaftye wrote:
It could be drilled. I'm talking about pumped fluid, not a liquid salt. Other options are good, I'm thinking aloud about how to use these fancy mills.

Guys, he already bought a heat pipe to do the initial testing, he knows its better than solid copper Silly I think it was discussed on page 2 or 3 or something.

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More than one of us can make things.

The low mode should be lower.

Reviews: Efan IMR18350 700mAh 10.5A, <a href="http://

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leaftye wrote:
More than one of us can make things.

Yes? And how is that relevant to the fact that heatpipes instead of solid copper was already suggested back in page two?

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Jerommel wrote:
bikedude wrote:
If you’re going to use heat pipes I’d suggest using a perpendicular head (think zebralight) for ease of manufacture.
I need a 6 inch alu tube section, maybe a 19” alu strip bent around in a circle. On it i will have to somehow fix the heat pipes which will be the boom that holds the LED. Is that what you meant?
Quote:
The laser design seems very effective but kinda dumb.
I thought it was a very nice idea actually, but unaffordable and as you say:
Quote:
Who wants to put on protective glasses every time he wants to use a flashlight? High power lasers can cause permanent severe damage to eyesight in a fraction of a second. To me that’s a big “Fu*n*k No” as far as using them when not absolutely necessary goes.
It’s not gonna be a laser exited phosphor. Smile

Bending heat pipes is difficult (wick must not be crimped, probably can’t bend multiple times due work hardening/embrittlement) and so is ensuring a tight fit to a heat sink. Fitting an U shaped pipe would require very precise bending while probably resulting in a larger head/more complicated heat sink design due to the required radius in the bend, an L piece would be slightly easier to mount but still tricky for the same reason and I guess centering of the mounted LED.
With an angled design there would be no radius to take into consideration and fit would basically be limited to lining up the contact surface of the HS to the rim of the reflector:

Imagine a cover over the heat pipe/heat sink contact area. My vector drawing skills aren’t too great Silly

Zebralight head lamp: https://eu.nkon.nl/magento17/media/catalog/product/cache/7/image/9df78ea... obviously much smaller light, it’s about the general idea.

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..waiting for parts..

Still looking for 5” parabolic reflector (for recoil light)

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No bending if used with a copper bezel, the heat pipe could be soldered/brazed to it, give the bezel a few fins and there is your cooling, also by using three pipes (merc symbol) it would not matter how it was orientated and give it the ability to hold the led at the focal point during rough use.
As far as using a large reflector the pipes would block less light % than using a smaller one Wink

Cheers David

Nothing to see here folks, move along...

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bikedude wrote:
Bending heat pipes is difficult (wick must not be crimped, probably can't bend multiple times due work hardening/embrittlement) and so is ensuring a tight fit to a heat sink. Fitting an U shaped pipe would require very precise bending while probably resulting in a larger head/more complicated heat sink design due to the required radius in the bend, an L piece would be slightly easier to mount but still tricky for the same reason and I guess centering of the mounted LED. With an angled design there would be no radius to take into consideration and fit would basically be limited to lining up the contact surface of the HS to the rim of the reflector: !http://i.imgur.com/TIOClEb.png! Imagine a cover over the heat pipe/heat sink contact area. My vector drawing skills aren't too great Silly Zebralight head lamp:  obviously much smaller light, it's about the general idea.

 

I think it's not hard to bend heat pipes, I have seen people just wrap them around a solid metal cylinder to get nice 90 degree angles.

With flat heat pipes it's even easier than round, all you need to do is check the minimum bend radius (usually mentioned by the manufacturer) based on the width and thickness, and then bend it a bit bigger than that.

There is always the risk of kinking it if not bent correctly, but doing a 90 degree large radius bend should require minimal skill.

I really like the idea of using an aluminum/metal cylinder as the body and just binding the heatpipe to that using thermal adhesive, makes it a lot sleeker on the outside while still having good cooling Smile

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Whether a ‘bezel with a few fins’ would be sufficient depends on the power consumption of the LED. Remember that the heat pipe itself does not provide substantial cooling, it just transfers heat from A to B.
Soldering is possible afaik although you can see how easy that is by trying to solder something to bare copper and then multiplying by ~10. Brazing will probably cause the pipe to burst. Thermal epoxy is viable and common but you still need a tight fit between HP and HS, arctic silver epoxy has a thermal conductivity of about 8W/mK, even small (<1.5 mm thickness) heat pipes have conductivities in the range of 700W/mK and higher.
Another reason why a decent heat sink is important: If you’re using something like an MTG2 the LED itself can stomach junction temps well over 100C. The heatpipe can’t, because water is a gas at 100C (assuming the whole HP/HS circuit reaches 100C or close enough).

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A page from the link I posted on page two, note they contain H2O.

Soldering is not only possible with a finished pipe but also gives optimal results Wink

I should of said brazing can be done during manufacturing while it is still just a pipe not a heat-pipe.

Water boils at 100c at sea level pressure, contain it and the pressure rises as does the boiling point, think of a steam engine the fire produces enough heat to instantly melt lead yet the water is held just below boiling point, at the other extreme water will both boil and freeze at the same time in space Big Smile

Cheers David

Nothing to see here folks, move along...

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I did a series of throw tests last evening on the cheapo plastic optical illusion reflector (mine is even unbranded chinese, I read above that there's quality differences even in these toys). I used a dedomed XP-E2 on 10mA current as light source and found that with the full size reflector there is not one focus, the middle part of the reflector does something completely different than the edge. Which is of course not good for throw. I wonder if this is inherent about a parabolic reflector used at these steep angles or that these optical illusion reflectors are particularly bad?

But this is the reflector I'm going to make a light out of, so I checked the hotspot brightness while varying which part of the reflector is used, from full size down to just 50mm diameter. I did this by laying the reflector upwards on the table and pointing the beam to the ceiling, and by placing pieces of cardboard with varying holes on top of the reflector I varied the reflector size. The led was positioned in the optimal focus point (that gave the highest spot brightness) using my XYZ-table. The highest luxreading in the hotspot was measured each time with a luxmeter.

Here are the luxvalues that I found, the numbers themselves have no exact meaning but they are a measure of spot brightness:

Full size (139mm) 946
90mm 898
80mm 881
70mm 865
60mm 858
50mm 663

As you can see, in this reflector it is quite pointless to go larger than 60mm (huge size increases with hardly any throw gain), the focal distance being 48mm this is about a 60 degrees cone of the led-beam. I was a bit surprised a this and I wonder if this is a general thing with recoil throwers, or that it is just a sign of using a bad reflector.

 

Fact is that 1) the (dedomed!) led has the highest brightness straight forward and clearly less close to 90 degrees to the side (it is in the led datasheets but I illustrated it a bit more visually below by positioning the used dedomed XP-E2 in the middle point of a piece of paper bended in a circle), and 2) that the imaging quality of the reflector is decreasing when going from the middle to the edge (I checked that by blocking defined parts of the reflector and watching the effect on the hotspot). In other words, it is a challenge to get enough light that is reflected by the edge of the reflector in the direction of the hotspot.

Extrapolating these results to the bigger 9-inch Mirascope reflector, a 90mm diameter section of that one should make the best size if a recoil thrower would be made with it.

I'm still overthinking what the influence has been of using the very small die dedomed XP-E2 (which was at hand) compared to leds with bigger dies.

 

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