Run-Time Plot - Milkbone

[Roy]

These runtime plots are for a Rayovac Industrial 2xAA flashlight that modded by CPF member "milkeyspit" and called the Milkbone. The light was reamed out to accept either AA or CR123 sized batteries.

Equipment used is an Extech Mdl 401021 Light adapter into a Radio Shack 22-805 multimeter with a PC interface that is using ScopeView software (V1.08).

The vertical axis is in 50mv per division which is equivalent to 50Fc @ 1Ft. The horizontal axis is in 30 minutes per division.

Be aware that your actual battery milage my vary from that indicated by thei runtime plot.

One CR123 Li battery used.

Two AA Everactive Alkaline used.

 

[Roy]

The battery tube has been reamed out to accept a spacer and one CR123 LI battery or two AA batteries. The mod also uses a high dome Q2H 1w led.

 

[milkyspit]

Thank you, Roy! The photo was a nice touch, too. /ubbthreads/images/graemlins/thumbsup.gif

 

[Bullzeyebill]

For two hours, forty-five minutes run time is almost identical for both battery types. Would have thought that CR123 would have had a flatter runtime. Q2H is very efficient.

Bill

 

[milkyspit]

Bullzeyebill, yes, the identical runtimes surprised me, too. But I was actually disappointed in the 2AA alkaline performance, because those cells contain more than twice the stored energy of the single 123 cell, and yet they couldn't do any better. In fact, they did WORSE from the perspective of steady output and gradual shutdown: with the alkalines, output diminished for the entire time, and once they reached the 2h 47m mark, they dropped like a stone. /ubbthreads/images/graemlins/frown.gif

That single little 123 cell IMHO made a nice showing. Output was pretty darned steady for the first 2 hours, and even when the cell was clearly reaching the end of its runtime, the output dropped gradually, over an extended period. At the 6h mark, for example, the light was still producing something like 20fc of output, whereas the 2AA alkalines at the 6h mark were pretty much flat as a pancake!

Well, I guess the Milkbone still proved one of its virtues, that it is capable of running different types of cells in a pinch. It'll even run okay using 1AA! Although of course a little dimmer than the 2AA case. I suspect that 2AA lithiums or 2AA NiMH rechargeables would provide runtimes more similar to the 123 cell graph, but with high output up to maybe the 4-5 hour mark before dropping too much.