Brinkman Legend AA Luxeon Mod (ver 1)

Reboot

Newly Enlightened
Joined
Jul 3, 2003
Messages
28
Location
Aloha, OR
I got some goodies in the mail yesterday. Wow, they light up! Up until this point, my Zetex circuits have only been powering up Luxeon simulators.
bmod_02.jpg


I removed the emitter from one of the stars, and soldered it to a waiting ZLT+ module.
bmod_07.jpg
bmod_08.jpg

The heatsink on top used to be a penny. And the contact point on the bottom used to be a thumb tack.

The module is a bit thick, so some trimming of the tail switch is required.
bmod_05.jpg


The Brinkman reflector turnes out to be too shallow to reach the Luxeon, so I use a spare M*g AA reflector. Here is the finished product next to my ARC-LS.
bmod_03.jpg


The center detail is lost by the camera. The ARC beam is actualy much better than the modified Brinkman. And the ARC would have been brighter if I was using the CR123A battery pack. But it has used AA's in it whereas my Brinkman has fresh ones. I only have one more M*g reflector, so I think I need to order some 30mm optics and see how they look.
I think my next version will drop in the top of the Brinkman so as not to take up so much space in the battery tube. I don't want to have to modify any more switches. A hack saw, Drimmel tool, and file make for a lengthy mod process. (I need better tools.)
 

Rothrandir

Flashaholic
Joined
Aug 17, 2002
Messages
7,795
Location
US
very nice!

i'm always impressed when i see these kind of things done with handtools! /ubbthreads/images/graemlins/eek.gif /ubbthreads/images/graemlins/icon15.gif
 

robk

Enlightened
Joined
Mar 11, 2003
Messages
608
Location
Near Daytona Beach, FL
Regarding the mod to the tail switch, my sandwiches are thick also and I found an easy way to deal with it. Simply cut a cardboard (thin) disk about .55" dia, poke a hole in it for the spring to stick through, place it over the spring - it prevents the brass nut from contacting the battery negative.
Rob
 

Rothrandir

Flashaholic
Joined
Aug 17, 2002
Messages
7,795
Location
US
rob, i did the same thing, but with a small amount of electrical tape /ubbthreads/images/graemlins/smile.gif

wait a second!
did i read that you're using a penny as a heatsink? /ubbthreads/images/graemlins/eek.gif
 

Reboot

Newly Enlightened
Joined
Jul 3, 2003
Messages
28
Location
Aloha, OR
[ QUOTE ]
ridnarhtor said:
rob, i did the same thing, but with a small amount of electrical tape /ubbthreads/images/graemlins/smile.gif

wait a second!
did i read that you're using a penny as a heatsink? /ubbthreads/images/graemlins/eek.gif

[/ QUOTE ]

Yep. An all copper one too. The Luxeon emitter is soldered directly to the former penny. And the rim of the flashlight has a thin coating of Arctic Silver to aid in the heat transfer to the body. But I may have over did it. The light has been burning for about an hour and a half now and it just refuses to get warm. I think I'll up the current on my next one.
 

Rothrandir

Flashaholic
Joined
Aug 17, 2002
Messages
7,795
Location
US
/ubbthreads/images/graemlins/eek.gif !

what level are you dribing it at?
did you smooth the penny out at all?
the text and pictures on the penny could be causing poor thermal contact...
 

Reboot

Newly Enlightened
Joined
Jul 3, 2003
Messages
28
Location
Aloha, OR
[ QUOTE ]
ridnarhtor said:
/ubbthreads/images/graemlins/eek.gif !

what level are you dribing it at?
did you smooth the penny out at all?
the text and pictures on the penny could be causing poor thermal contact...

[/ QUOTE ]

Driving at a conservative 350ma. And the heatsink formally known as penny is almost as smooth as a copper clad board. I have endeavored to make the heat transfer path from the emitter to the body of the flashlight as efficient as possible. I believe I somewhat succeeded because when I unscrew the top and feel the emitter, it is a cool as the rest of the flashlight. What heat there is must be getting distributed throughout the body an dI just can't feel it.
 

Reboot

Newly Enlightened
Joined
Jul 3, 2003
Messages
28
Location
Aloha, OR
I've got a couple ideas why these are not getting warm like I expected.

1. The heat transfer mechanism to the body is very effective.
2. The Luxeons are actually under-driven... I adjusted for 350ma of current in the 3-diode Luxeon simulator which has a voltage drop of 3.0V. The actual emitter has a voltage drop of 3.4V. So I should have used a 4-diode simulator with a drop of 3.6V to set the current. Then I would have wound up over-driving the Luxeon a bit and would have the heat I was expecting.

I adjusted the current in my remaining un-epoxied Zetex driver using the 4-diode simulator to 330ma. This gives 450ma in the 3-diode simulator. So I'm guessing I may wind up with slightly over 350ma driving the actual emitter. (I suppose I should hook a 0.1 ohm resistor in series with the emitter and see what I'm really getting. But I don't have one.)
 

NightStorm

Flashlight Enthusiast
Joined
Jun 16, 2002
Messages
1,090
Location
Between a rock & a hard place.
Roth,

A pre-1959 penny is almost pure copper. After 1959 they are copper cladding on a zinc core (and the thermal transmission rate of zinc is poor). Another good source for small amounts "Electrical Copper" are the contact ends of 250v NON-100, 100 amp fuses. Just thought ya' like to know.

Dan
 

Rothrandir

Flashaholic
Joined
Aug 17, 2002
Messages
7,795
Location
US
yes, my main concern was the non-smooth surface though. as long as he has that taken care of, i'm not too worried /ubbthreads/images/graemlins/smile.gif (it's still probably thicker than the metal area on the dropin pills.)
 
Top