Some of you might remember the original Aurora flashlight project. That was a modding challenge I undertook starting in the winter of 2003. It was strictly an exercise in determining the limits of what was possible in terms of jamming the most power and lumens into a tube torch body the size of a standard 3D. The original teaser thread is here and the release thread is here. The end result was a 100W light in the body of a stock-appearing, lime green Mag3D that pumped out as much as 4,000 bulb lumens.
Since then, the original Aurora prototype has mostly been sitting on my dresser although it did make a trip to Photon Fest 3 hosted by Milkyspit. Also, several folks have endeavored to produce a commercial run of lights based on the original concept. Out of all of these, only Bill Waites' USL project has seen the light of day. There are numerous threads related to the USL so I won't link to them, but I will say that he has raised the phenomenon of a flashlight build to a new level. The USL'ers have developed into a bona fide mini-community which seems to have more fun than any other bunch of guys on the board.
The Aurora prototype was a rough unit and I've always longed for a more evolved version even though I knew I could never support a build. And so I contacted a few of my fellow hot wire modders and solicited their support to make just one more Aurora. The Aurora2 would not exist were it not for the following folks.
bwaites: One of the most enterprising and friendly individuals I've met in my time here. We first met when he contacted me to inquire about collaborating on an Aurora production run. Although I just didn't have the resources to support one, our numerous conversations regarding the design led me to the conclusion that Bill was a genuine star, honest, perceptive and humble. Bill supplied the Mule prototype body used in the Aurora2.
js: Jim has already earned his fame and respect by blazing the trail with his family of TigerLight mods and the innovative M6-R power pack. And this is just his latest, most popular work. If there's a more rigorous, intelligently critical flashlight modder working today, I haven't met him. Jim shared with me his thoughts, ideas and concerns on all aspects of high powered incandescents from the bulb to power systems to testing. Jim supplied the custom-modified reflector for the 2" head.
fivemega: Varooj has become one of the most intelligent, productive and astute production modders around. His work is amazing and sets the standard in craftsmanship and design. Just check out his AA-D battery carriers, fat-body heads and lights and lithium ion adapter systems. He is generous and honest and shares freely his ideas as well as his questions. Varooj supplied the FM3-V head.
all the fans of high-powered incandescent lights: My humble thanks to all of you for sharing your energy, ideas and love of the hot wire. I put in the time and effort that I do for you guys as much as for my own satisfaction. Thanks for demonstrating to me again and again that incandescent lights are not an obsolete technology but still vital and dare I say, sexy.
I'm known for my long posts but I'll try to keep it short this time. Here are the vitals:
Body: The body came to me as a bare aluminum "Mule" prototype. It accommodates a triangular triple stack of 4/5A cell, four long in each string. So, up to 12 cells of this size can fit inside the body. Designed from scratch to accommodate this potent cell, the walls are thick and strong. The head end is a perfect replica of the threads and O-ring groove of the Mag. This makes it capable of accepting any stock or custom Mag head. The tailcap, unlike in the Mag, is an externally threaded unit which allows the body wall to continue at full thickness to the very end. The switch opening is specially designed to accept the snap-in, industrial mini-rocker switch. These tiny units are capable of handling 10A with no reliability issues.
The original finish was heavy on the knurling and raw as-machined from the mill. I filed down the knurling so that the high points were completely flush with the body surface. The subsurface knurling remained. I then smoothed down the surface using a progression of wet sanding terminating in 2000 grit. I topped this off with a buffing to mirror polish. The end result is something I call "holographic knurling." The effect is totally unlike traditional knurling such as you would find on SureFire lights. When held lightly, the surface feels smooth yet rippley, almost like a liquid leather. But if you grip the tube with force, the knurling locks up with your fingers providing a secure grip.
3" Turbo Head: The head started out as a complete hard anodized FM3-V unit. I stripped the anodizing, revealing the massive chunk of aluminum. Those of you who own FM3 heads will know what I'm talking about...this is one massive hunk of metal. I took a hand file to the fins to change the profile as I wanted something even more distinctive. The end result is a two-step profile with a more traditional main head "cup" with a slimmer transition section. The front bezel ring and head were then treated to the same sanding sequence as the body. All sharp edges were given just the slightest chamfer to clean things up. The reflector was designed to provide cam action focusing but since this was not required for the Aurora design, I cut the cam stub off.
2" Compact Head: This started out as a stock Mag D unit. I stripped the anodizing and then filed away the knurled grip ring around the head section eventually undercutting it to give a totally different effect from the original. The writing on the front bezel ring was obliterated. Everything was sanded and buffed. The reflector is a medium orange peel (MOP) unit custom worked by js to function optimally with the Aurora2 bulb mount system.
All the body and head parts were then sent out for electroless nickel plating. This finish is durable, smooth and provides a warmer, more elegant color cast than either bare aluminum or bright chrome. It's my favorite.
Here are some pictures of the body and head parts both before and after electroless nickel plating.
Power System: The Aurora2 uses a pack that is an upgrade from the original Aurora pack in several ways. First, instead of the occasionally problematic KAN1800 4/5A, I switched to GoldPeak GP2000 4/5A. GP's high current cells are the standard in the field of radio control modeling and with good reason. They are bulletproof and perform at amazing levels. Second, the Aurora2 pack uses 12 cells instead of 11. Here's the snapshot of performance: 10.5+ amps peak delivery, 9.25 amps sustained at MPV, 1.174V MPV. MPV is the "midpoint voltage" or the point of delivery of 50% of capacity. This means each one of these cells which is the same diameter as a CR123 and only 15mm longer is putting out nearly 11 watts of power or over three times what a cell driving the WA01185 superbulb is called upon to deliver. And it's doing it after half the usable capacity has been delivered. All joints are soldered as before and turn-around connections are made with solid copper strips. The pack is doubly shrink-wrapped and reinforced with Kapton tape and protective copper/silicone sandwich endcaps.
For the frequently used connectors, I switched from fully insulated blade connectors to Dean's Ultra plugs. The battery side connector was additionally potted in epoxy to provide extra protection and durability. The pack can now be charged simply by unscrewing the tailcap, disconnecting the pack from the switch circuit and plugging in a mating Dean's Ultra charging harness. Here are some power delivery curves for the new power pack. You'll see that this pack will push a 100W bulb to an average of 127W and 130W at MPV. Note the flatness of the voltage discharge curve even at an average of 9.25 amps or 4.6C rate. These are simply amazing cells.
Light Engine: Now that the power pack is a 12-cell unit, it is no longer possible to use short-life bulbs in the Aurora2. Bulbs such as the Osram 62138HLX axial and 64625HLX will blow due to the extreme level of overdrive. To survive the initial 16.5V, 10.5A inrush, the bulb must have a rated life of 2,000 hours or better. The bulb of choice is now the Osram 64623HLX. Funny how things sometimes come full circle. This was one of the very first bulbs used in the original Aurora. Pumping 2,800 lumens at spec, this is the brightest 100W long life bulb available. The fact that it has a horizontal filament is hardly an issue since driven by the Aurora2 power pack, this bulb will produce 4,900 lumens at MPV and that's after 5 minutes of constant on time. In your first 30 second squirt, expect to see nearly 6,000 bulb lumens. In a word, it's very bright. Here is how the bulb puts out.
I also calculated the luminous efficiency based on the power measurements. So, for those who keep knocking incandescents for their inefficiency, you'll see that this bulb operates at better than 35 lumens/watt for most of its run. Not bad at all for a tiny piece of glowing metal.
Here's a beamshot. The target is a 13-story apartment complex on the next block. I normally do not shine my lights at other people's houses but there are very few good ranges near our new house and I was in the city for a visit. "Quick on - snap - quick off" to try to minimize any disruption or disturbance. Net on-time of about 2 seconds.
And just one or two more indulgent photos to leave off with.
And one picture with the only other electroless nickel plated light I've made, the U-binned Smooth Operator based on McG's Aleph 2.
Well, that's it folks. Here is Aurora2 packed in its own Pelican 1500 case, ready to go to my friend PaulW to play with. This light is the culmination of my hot wire aspirations and is my "statement" piece. There will not be another one like it. Still, someday, it may leave my hands and find a home with another who would cherish it as much as I.
Finally, like all good things, this journey must also come to an end. After I've completed the Polaris build (and possibly the 1/2D GB) I'll be taking an indefinite leave from CPF. I have realized almost every flashlight dream I've had and now seems like the right time to step away and refresh. They say that when you run out of dreams, "go get some sleep and make some new ones."
Well, I hope you've enjoyed the final chapter in the Aurora saga. It's been a total blast! Thanks to all my friends, colleagues and supporters. And my best wishes to all who worship the hot wire...keep the tungsten boiling and run time be damned!
Fond Regards,
Wilkey
Since then, the original Aurora prototype has mostly been sitting on my dresser although it did make a trip to Photon Fest 3 hosted by Milkyspit. Also, several folks have endeavored to produce a commercial run of lights based on the original concept. Out of all of these, only Bill Waites' USL project has seen the light of day. There are numerous threads related to the USL so I won't link to them, but I will say that he has raised the phenomenon of a flashlight build to a new level. The USL'ers have developed into a bona fide mini-community which seems to have more fun than any other bunch of guys on the board.
The Aurora prototype was a rough unit and I've always longed for a more evolved version even though I knew I could never support a build. And so I contacted a few of my fellow hot wire modders and solicited their support to make just one more Aurora. The Aurora2 would not exist were it not for the following folks.
bwaites: One of the most enterprising and friendly individuals I've met in my time here. We first met when he contacted me to inquire about collaborating on an Aurora production run. Although I just didn't have the resources to support one, our numerous conversations regarding the design led me to the conclusion that Bill was a genuine star, honest, perceptive and humble. Bill supplied the Mule prototype body used in the Aurora2.
js: Jim has already earned his fame and respect by blazing the trail with his family of TigerLight mods and the innovative M6-R power pack. And this is just his latest, most popular work. If there's a more rigorous, intelligently critical flashlight modder working today, I haven't met him. Jim shared with me his thoughts, ideas and concerns on all aspects of high powered incandescents from the bulb to power systems to testing. Jim supplied the custom-modified reflector for the 2" head.
fivemega: Varooj has become one of the most intelligent, productive and astute production modders around. His work is amazing and sets the standard in craftsmanship and design. Just check out his AA-D battery carriers, fat-body heads and lights and lithium ion adapter systems. He is generous and honest and shares freely his ideas as well as his questions. Varooj supplied the FM3-V head.
all the fans of high-powered incandescent lights: My humble thanks to all of you for sharing your energy, ideas and love of the hot wire. I put in the time and effort that I do for you guys as much as for my own satisfaction. Thanks for demonstrating to me again and again that incandescent lights are not an obsolete technology but still vital and dare I say, sexy.
I'm known for my long posts but I'll try to keep it short this time. Here are the vitals:
Body: The body came to me as a bare aluminum "Mule" prototype. It accommodates a triangular triple stack of 4/5A cell, four long in each string. So, up to 12 cells of this size can fit inside the body. Designed from scratch to accommodate this potent cell, the walls are thick and strong. The head end is a perfect replica of the threads and O-ring groove of the Mag. This makes it capable of accepting any stock or custom Mag head. The tailcap, unlike in the Mag, is an externally threaded unit which allows the body wall to continue at full thickness to the very end. The switch opening is specially designed to accept the snap-in, industrial mini-rocker switch. These tiny units are capable of handling 10A with no reliability issues.
The original finish was heavy on the knurling and raw as-machined from the mill. I filed down the knurling so that the high points were completely flush with the body surface. The subsurface knurling remained. I then smoothed down the surface using a progression of wet sanding terminating in 2000 grit. I topped this off with a buffing to mirror polish. The end result is something I call "holographic knurling." The effect is totally unlike traditional knurling such as you would find on SureFire lights. When held lightly, the surface feels smooth yet rippley, almost like a liquid leather. But if you grip the tube with force, the knurling locks up with your fingers providing a secure grip.
3" Turbo Head: The head started out as a complete hard anodized FM3-V unit. I stripped the anodizing, revealing the massive chunk of aluminum. Those of you who own FM3 heads will know what I'm talking about...this is one massive hunk of metal. I took a hand file to the fins to change the profile as I wanted something even more distinctive. The end result is a two-step profile with a more traditional main head "cup" with a slimmer transition section. The front bezel ring and head were then treated to the same sanding sequence as the body. All sharp edges were given just the slightest chamfer to clean things up. The reflector was designed to provide cam action focusing but since this was not required for the Aurora design, I cut the cam stub off.
2" Compact Head: This started out as a stock Mag D unit. I stripped the anodizing and then filed away the knurled grip ring around the head section eventually undercutting it to give a totally different effect from the original. The writing on the front bezel ring was obliterated. Everything was sanded and buffed. The reflector is a medium orange peel (MOP) unit custom worked by js to function optimally with the Aurora2 bulb mount system.
All the body and head parts were then sent out for electroless nickel plating. This finish is durable, smooth and provides a warmer, more elegant color cast than either bare aluminum or bright chrome. It's my favorite.
Here are some pictures of the body and head parts both before and after electroless nickel plating.
Power System: The Aurora2 uses a pack that is an upgrade from the original Aurora pack in several ways. First, instead of the occasionally problematic KAN1800 4/5A, I switched to GoldPeak GP2000 4/5A. GP's high current cells are the standard in the field of radio control modeling and with good reason. They are bulletproof and perform at amazing levels. Second, the Aurora2 pack uses 12 cells instead of 11. Here's the snapshot of performance: 10.5+ amps peak delivery, 9.25 amps sustained at MPV, 1.174V MPV. MPV is the "midpoint voltage" or the point of delivery of 50% of capacity. This means each one of these cells which is the same diameter as a CR123 and only 15mm longer is putting out nearly 11 watts of power or over three times what a cell driving the WA01185 superbulb is called upon to deliver. And it's doing it after half the usable capacity has been delivered. All joints are soldered as before and turn-around connections are made with solid copper strips. The pack is doubly shrink-wrapped and reinforced with Kapton tape and protective copper/silicone sandwich endcaps.
For the frequently used connectors, I switched from fully insulated blade connectors to Dean's Ultra plugs. The battery side connector was additionally potted in epoxy to provide extra protection and durability. The pack can now be charged simply by unscrewing the tailcap, disconnecting the pack from the switch circuit and plugging in a mating Dean's Ultra charging harness. Here are some power delivery curves for the new power pack. You'll see that this pack will push a 100W bulb to an average of 127W and 130W at MPV. Note the flatness of the voltage discharge curve even at an average of 9.25 amps or 4.6C rate. These are simply amazing cells.
Light Engine: Now that the power pack is a 12-cell unit, it is no longer possible to use short-life bulbs in the Aurora2. Bulbs such as the Osram 62138HLX axial and 64625HLX will blow due to the extreme level of overdrive. To survive the initial 16.5V, 10.5A inrush, the bulb must have a rated life of 2,000 hours or better. The bulb of choice is now the Osram 64623HLX. Funny how things sometimes come full circle. This was one of the very first bulbs used in the original Aurora. Pumping 2,800 lumens at spec, this is the brightest 100W long life bulb available. The fact that it has a horizontal filament is hardly an issue since driven by the Aurora2 power pack, this bulb will produce 4,900 lumens at MPV and that's after 5 minutes of constant on time. In your first 30 second squirt, expect to see nearly 6,000 bulb lumens. In a word, it's very bright. Here is how the bulb puts out.
I also calculated the luminous efficiency based on the power measurements. So, for those who keep knocking incandescents for their inefficiency, you'll see that this bulb operates at better than 35 lumens/watt for most of its run. Not bad at all for a tiny piece of glowing metal.
Here's a beamshot. The target is a 13-story apartment complex on the next block. I normally do not shine my lights at other people's houses but there are very few good ranges near our new house and I was in the city for a visit. "Quick on - snap - quick off" to try to minimize any disruption or disturbance. Net on-time of about 2 seconds.
And just one or two more indulgent photos to leave off with.
And one picture with the only other electroless nickel plated light I've made, the U-binned Smooth Operator based on McG's Aleph 2.
Well, that's it folks. Here is Aurora2 packed in its own Pelican 1500 case, ready to go to my friend PaulW to play with. This light is the culmination of my hot wire aspirations and is my "statement" piece. There will not be another one like it. Still, someday, it may leave my hands and find a home with another who would cherish it as much as I.
Finally, like all good things, this journey must also come to an end. After I've completed the Polaris build (and possibly the 1/2D GB) I'll be taking an indefinite leave from CPF. I have realized almost every flashlight dream I've had and now seems like the right time to step away and refresh. They say that when you run out of dreams, "go get some sleep and make some new ones."
Well, I hope you've enjoyed the final chapter in the Aurora saga. It's been a total blast! Thanks to all my friends, colleagues and supporters. And my best wishes to all who worship the hot wire...keep the tungsten boiling and run time be damned!
Fond Regards,
Wilkey
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