# MAKE a FLASHLIGHT THAT DOESN'T NEED REPLACEMENT BULBS OR BATTERIES!

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A couple of years ago, I made a forever flashlight mostly out of old parts I found laying around.  This was the video I made of how I built it and how it turned out.

http://www.thekingofrandom.com

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## 30 Discussions

I wonder if you were to use two or three separate coils along the length and wire them in parallel to the Bridge Rectifier, would that help build charge more quickly? I haven't tried it, so I am just wondering your thoughts.

This is not near as easy as we are lead to believe. I tried this with 300 wraps, then 500, now 800 wraps before I ever got sufficient voltage. Also I tried it with 1 inch pvc and then found that 3/4 works better, and in fact I used my table saw to make a 1.5 inch groove 1/2 way through the pipe wall in the middle of the pipe so that the windings would be closer to the magnet. I recommend 28-34 gauge wire to make the winding smaller. Be advised that the smaller the wire gauge the higher the voltage, but the lower the amperage. Amperage = the actual power flow.

I have a question or two: You didn't say where the poles of the magnet are. Are they on the ends, or the sides? Also, why did you use 1 inch pvc? The magnet fits much better into 3/4.

Thanks

Using a bicycle speedometer to count 300 wire wraps.

Connect the magnet to the pvc pipe, and the sensor next to it. Make the pipe so it can easily be spun in place.

Circumference of 26 inch bicycle wheel 81.64 (wheel diameter x 3.14)

1 mile converted to feet 5280
1 mile converted to inches 63360
1 mile converted to 81.64 inch units 776.0901519
4 tenths of a mile is this many 81.64 inch units 310.4360608

Keep spinning the pipe until the bike speedometer says .4 of a mile, and you have sufficient wire wraps.

What would be the result of wrapping a single wire layer down most of the length of the pvc? Better? Worse? Not workable? Just curious.

Just one question, since no other storage component is listed, is the capacitor supplying the power for the run time?