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Easy Maglite P7 Mod! Nice...

randomlugia

randomlugia

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Is that before or after dividing it? Because if you didn't that's a ton of current for the LED. If it hasn't popped yet and you've got good heatsinking, it probably isn't a problem though.

There is a driver in the Malkoff; they've got really nice current regulation.
 





jayrob

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All of the measurements I've mentioned are direct readings from my meter. No division or anything...

I just put fresh charged batteries in my dual 18650 P7, and I get 2 Amps current draw at the batteries with UltraFire. It will draw 2.6 Amps with AW's.

Still, side by side with this Maglite P7 mod, the Maglite is a little brighter. But the current draw from the dual 32600's is only 1360 to 1390mA's. I tried it with the AW's and got the same reading... (no division)
 
randomlugia

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Then I really have no idea why it's brighter... Maybe one of our LED experts will chime in soon.
 
jayrob

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randomlugia said:
Then I really have no idea why it's brighter... Maybe one of our LED experts will chime in soon.
Click to expand...

Well it's not super brighter. The other light is very comparable...

But side by side, I can see a little brighter flood area with the Maglite.

The big difference is in the amount of battery current draw. Unless I'm missing something, this tells me how long I can expect my batteries to last by calculating the battery current draw vs the capacity of the batteries...

So the one light will probably only last an hour or so. But the Maglite build should last maybe 3 1/2 hours.

If my thinking is flawed in this assumption, please advise! (I'm mostly into building lasers, but getting into Flashlights now)
 
randomlugia

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That thinking is a little bit flawed, not much. Getting back to my point about better flashlights, current regulation is everything. A light with good regulation will be at full brightness for the entire battery life and suddenly cut off. A light that's directly driven or has a cheaper driver will slowly slope down in brightness throughout the battery life. Doing so will extend the runtime, but obviously the light won't stay bright and you'll have to keep the batteries topped off to keep it bright. Another factor, you can't completely drain the battery, only to about 3.0-3.2 volts. Really the only way to test runtime is to actually test it.

It should last longer than an hour, my 3A driven P7 lasts an hour on an 18650. Those 32600 batteries have twice the capacity. 5000mAh, right?

Beamshots? :D
 
jayrob

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I'll get a beam shot tonight when it gets dark... :)


I figured that since I have an 8.4 volt supply (full charge), and maybe 6 volts at time for charging, that the driver will not need to pull extra current for any boosting like we do with blu-ray diodes and boost drives for a single Li-Ion build...

So I'm thinking that my run time will be maybe 3 1/2 hours before charging will be needed. But yeah, I realize that the only way to know for sure, is to test it...

How much forward voltage does a P7 emitter take?






Update - Adding some extra heatsinking for the P7:

Since I like very much the way this easy build came out, and I think I got a nice P7 module, I went ahead and added some extra heatsinking for it! :)

Mag%20P7%2014.jpg

Mag%20P7%2015.jpg


Might as well make this bad boy a little more comfortable in it's new home! (adding this to the first post)
 
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randomlugia

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I'm not sure about the forward voltage of a P7, it varies between emitters. The best I can tell you is that it will usually pull between 1.8 and 4.5 amps at 4.2V, from reading reviews and personal experience.
 
jayrob

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Ok cool... I knew it had to be less than 6 volts...

Which means that my current draw from the batteries won't go up as the voltage drops...

Here's a beam shot that I'm going to also add to the first post...

The face of the cave on my pool where the steps are, is 60' away, and the very back corner at the fence is 85'... :)

Mag%20P7%2016.jpg
 
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jayrob

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randomlugia said:
That's looking really cool!



Yeah, that's what the drivers are for.
Click to expand...


Well I only said that about the current draw, because depending on what type of driver/supply you have, the current can actually go up as the voltage drops...

Such as the popular FlexDrives with a single Li-Ion driving a diode that is asking for more voltage than the battery has.

In that case, the boost driver uses extra current to give the diode what ever voltage it demands.

And as the battery drops in voltage during use, it actually must provide more and more current as it drains...

Anyway, this build is pretty solid using the high capacity Li-Ion 32600's. I just may put some 6000mAh 32650's in this bad boy! :D

Which would fit with a little extra tail cap modification. And would add nearly an extra hour of run time between charges! :)
 
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randomlugia

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I think I know what you mean, even though DIY laser stuff has always baffled me. Where can you get the 32650's? I looked but couldn't find any.
 
jayrob

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There are a couple of sources I have linked right in the first post! :)

I know Kaidomain has them, that's where I have been ordering from. Plus DTR got me a couple of the exact same ones but from a different source...
 
randomlugia

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Either it's not there or I'm still not seeing it... Search on KD also got no results. Sorry could you link it here?
 
jayrob

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Oh sorry!

I need to read your question better! I thought you meant 32600's.

Here's a link to the 32650's. DTR told me that he has some on the way. I'm not sure yet if they have more stock. Because it says 'out of stock'. I messaged them just today actually. But they have not returned my message yet...
D (32650) Lithium-ion Battery (2 cells)_Battery | Charger_
 
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