Legend 3AA LS Mod -- On LITHIUMS...

[**DONOTDELETE**]

Wayne,

Thans kindly, after all it was you and Lambda's stuff what inspired this usually "plug 'n play" (or is it pay?) guy...

 

[**DONOTDELETE**]

I ran the LGI for temps tonight, had it on for over 45 minutes and although it did get very warm, especially right at the head/body threaded joint, it never got hot.

It begins to warm up almost immediately, but the temperature seems to stabilize after five or ten minutes.

Nice and warm to hold, just a tad warmer than my Lambda Illuminator, but cool enough that I could press it firmly against my bare chest without discomfort. I have no laser temperature thermometer, but I am confident this has now become a fully usable light even in extended operation situations.

 

[**DONOTDELETE**]

Just did the unthinkable. Tested this already overdriven light with three lithiums, and it metered a crazy 708 lux. Only left it on for the few seconds it took to get a stable reading, however, as I don't need a long skinny paperweight just right now.

 

[Slick]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by MR Bulk™:
Just did the unthinkable. Tested this already overdriven light with three lithiums, and it metered a crazy 708 lux. Only left it on for the few seconds it took to get a stable reading, however, as I don't need a long skinny paperweight just right now.<HR></BLOCKQUOTE>

Holy Moly!! That's nearly "stun territory"...

Once I get my other 3 units built, I'll try the nastiest looking LS with the lithiums and get a power consumption reading. As long as it doesn't keep climbing, I would assume that it's not in thermal run-a-way.

I need to look into getting a light meter so I can compare power consumption vs. lux produced..

My only intent would only be momentary use.. - and for starting campfires too.

 

[txwest]

Mr B,
Don't count on switching to rechargeables to save your lamps. I destroyed 2 of them direct drive on rechargeables. I had a thread going getting different opinions about this just prior to the 1st CPF shutdown. Seemed to be the general consensis that even at 3.6V, the LS was being overdriven to the point of burning up. TX

 

[**DONOTDELETE**]

txwest,

No, I won't be using rechargeables. I like the brightness of alkalines, and even if the LS eventually goes south, I will simply replace it -- consider it an eventual "bulb change", although I would hope it occurred at far less frequent intervals than compared to incandescents...

 

[splitsec524]

Where do I buy a 3AA flashlight so I can try this mod out???

 

[**DONOTDELETE**]

They sell'em direct from the Brinkmann site for $18.95 shipped, and a search (I used yahoo.com) did not turn up any for less.

 

[splitsec524]

Hey guys what else would be good heatsinks? I've scoured all the hardware stores but none has copper washers. Would brass be ok? Or what other metals have good heat transfer properties?

 

[**DONOTDELETE**]

I have had good luck with aluminum, and the Masters here all use it so i simply followed their advice. Plus it is relatively inexpensive.

 

[ElektroLumens]

A copper penny works great for a heat sink. Just file smooth one side. Fits perfectly into the head, the LS mounts on it, and the collimator fits in just right!

Wayne
www.elektrolumens.com

 

[bucken]

Yeah, and it only costs .01, too!

(Sorry, Wayne, just couldn't resist. You probably won't get it unless you've seen the Aflack commercial.)

 

[**DONOTDELETE**]

Hmmmm...I tried this out tonight Wayne, and I'm sure you can use this style of heatsink for the way you are modding the Legend, but I can't use one that thin. I find that the sink on the left is the diameter and thickness I need for optimal heatsinking the way I have been doing it:

Got one from Lambda to use and have been cutting mine that way too from 1/8-inch thick sheet aluminum. Just seems the thickness would wick away more heat from the top of the tube lip which is where I stick mine on with Arctic Silver (I haven't figured a good way to put it into the head like how you do), and if I sanded Linclon's head completely off it'd be even thinner, so I quit...

 

[ElektroLumens]

Originally posted by MR Bulk™:
[QB]Hmmmm...I tried this out tonight Wayne, and I'm sure you can use this style of heatsink for the way you are modding the Legend, but I can't use one that thin. I find that the sink on the left is the diameter and thickness I need for optimal heatsinking the way I have been doing it:

<font size="2" face="Verdana, Arial">I normally use 1/4" thick aluminum stock, and cut it to fit. Works great, but is a lot of work. I had a machinest do some discs for me, but it's expensive. I have a circle cutter, which mounts in a drill press, and works for larger sizes. But for the 3/4" diameter, I'm exploring possibilities. I noticed a penny is the correct diameter, and it is a copper alloy. So I decided to try it, and it seems to work quite well. I am using it in a flashlight, direct drive, in a Brinkmann 3AA, and it is sinking quite well. Not sure how much harder you're driving yours than I am mine, but anyway, it seems to work.

I am going to get a 3/4" aluminum rod as soon as I can get over to the metals supplier. I can slice off discs, any thickness I need that way.

It seems Brinkmann has redesigned the inside of their 3 AA flashlight, as it is different from the last one I did (purchased about 1 year ago). I didn't need to machine out the inside (using a 3/4" drill bit), as now it is 3/4" on the inside diameter. Seems like they have deliberately changed the design of the head so it will work (much easier) with the Luxeon Star?

Perhaps all of a sudden their dead stock 3AA flashlights are moving, and they know why, and want to facilitate it? (Just an assumption here.)

Regarding the copper penny, pennies dated from 1962 to 1981 will be 95% copper and 5% zinc. Newer pennies are 99.02% zinc, and .08% copper, with pure copper plating. The pennies that are 95% copper should work for heat sink quite well.

Wayne
www.elektrolumens.com