Picture of the pvc flashlight
This is it the amazing flashlight made frome scrap parts got all the parts from the shack and home depot. Its fancy switch and everything

Step 1: Gather parts

Picture of gather parts
i got all my parts from the home depot and the shack

radio shack:
A 3 10mm red leds
B 1 push on push off switch
C 3 9v battey clips
D 3 9v batteries
E some wire
F a 560 ohm resistor

home depot:
a:1 pvc pipe atleast 8 inches long
b:1 male threded connecter
c:1 1" to 2" expander
d:1 female threaded end

! hot glue gun
@ soddering iron
# sodder
$ drill
% hack saw

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michaelgc1 year ago

Nice little project flashlight. This is something I might be able to do for my stem class.

ianskiin7 years ago
i was thinking of constructing something similar to this, but with many more leds, about 10 to 15. could i run them all in series off one nine volt battery? that was what i was thinking, but i have no clue what type of resistor to use or if i need more power.
Search, Google or otherwise, for "led calc" or "led array calc". There are a number of good web-based calculators to help you figure out the right size resistor for any number of LEDs with any current and voltage requirements, hooked up to any DC source. Each LED needs its own resistor (bad idea to use one resistor for all LEDs) so if you calculate one resistor for one LED, you can safely use the same resistor size for all the other LEDs as well.

Looking at your specific problem, there's no limit, really, to how many LEDs you can hook up to one battery. The only consideration is how long you want them to be lit, which is controlled by the Amp-hours (Ah) of a battery and the Amps used by each LED. One type of high-intensity LED I have in my parts case needs 25mA (milliamps). A 9v battery typically has 550 mAh (milliamp-hours). So hooking up 15 LEDs at 25mA each requires 375 mAh, which means this LED flashlight will run for about one and a half hours (550 mAh divided by 375 mA = 1.47) with that setup. Each of my 15 25mA LEDs will need its own 220 ohm resistor.
I made a 9 volt battery flashlight with 12 leds. you'll need to make sets of three in series to limit each led's current to 3 volts, and then after that just wire those sets in parallel until you have however many you want.
I had a small sign that ran 13 leds in series off of one 9v battery, so it might work.
If you know the voltage of your LEDs, it's easy to figure out how to set it up. I used one 9v and LEDs of 1.5v each. 9x1.5 is 6, so I put 6 in a series and connected it to the 9v (each LED acts as a resistor and removes 1.5v from the circut). If you want more LEDs in the flashlight, make more sets of 6 or whatever and connect the sets in parallel. If you dont know the proper voltage and want to avoid resistors, temporarily hook up all of your LEDs in a series to a 9v and remove one at a time until they are at maximum performance.
Local law enforcement would have a fit if they saw this in your hand!! Looks like a pipe bomb to me. Be careful!
Paint it bright orange with a neon green stripe or two. Terrorists usually don't bother with painting their pipe bombs, and certainly not in such "LOOK AT MEEEEE!!!" colors. Plus you want to be able to see it easily when you are hunting for it in the dark.
A pipe bomb made of plastic? Doesn't seem very effective.
terrorists are dumb sometimes.
diaper guy?
webgiant1 year ago
With a second 1" to 2" expander, you could recess the switch in the base of the flashlight. The second expander would be mounted around the cap on the end, 2" end surrounding the cap, with the switch inside the 1" end of the second expander. This would make the flashlight not have that pushbutton switch sticking out halfway down the length.
finn123452 years ago
how long should the long wires be
rownhunt7 years ago
I need some help?? what resistor should is use for
THIS LEDit is the
Cree XLamp XR-E 7090 Q4 (Cool White)

depeneds on the voltage you are feeding it, it also depends on your led, different leds have different forward recommended voltages so depend on your led when determine the resistor.
Try a 470 ohm and gradually work ur way up
plumber45 years ago
Or...you could just buy a flashlight. Kidding, neat little project to do with the kids. cool.
why would you buy a flashlight? I mean, I recently made a flashlight to rival any store-bought one (12 high intensity LEDS!) and it cost me a whopping total of 72 cents, what with all the parts laying around. the only things I bought were the leds themselves.
Or you could build one that acutaly puts out some light, like mine, 5x cree r5.
beehard444 years ago
just made the body of it and used bottle caps with the tops of 2L bottles as couplers
waiting for the epoxy to dry...
this would be a good flashlight case for a Halogen light or LED Halogen
could you post a video of you making this?
nice project man. I used to work for the shack. I have a "fireworks" detonator that we made with parts from there. it is huge and I can set off 8 "things" at a time. pretty sweet.
Pwag6 years ago
i like it, it looks like a pipe bomb
Derin7 years ago
mine will have nimh and a dock
X_D_3_M_17 years ago
is that... glitter carpet?
robodud3 (author)  X_D_3_M_17 years ago
no that would be a wooden table, concrete, concrete, and a wooden table again
Drackar8 years ago
One statement, one question. First, "scraps" are usually things you have laying around. Not things you go out and buy. Secondly. Why do you need 27 volts for this? You could just as easily run it on one nine volt, or have cheaper power from a couple of AAA's, and a smaller resistor.
He is running this on 9 volts. The batteries need to be re-wired to be properly in parallel. I personally agree that 6 AA or AAA batteries in series would be cheaper and supply longer life. I'd also add a couple more LEDs. There's plenty of room for more.
6 or 9 more LED's?
The whole point is that he doesn't NEED to run it on nine volts. He could run it on three just as easily. He's over-powering for the LED's. I have a three LED flashlight that runs on three AAA's. If he wanted to go up to say a..oh. Ten LED flashlight? I'd have ONE nine volt in there, and calculate the right resistance, and put the right ten cent parts in there. It's heavyer than it needs to be. It has WAY more voltage than it could need. Even your six AA/AAA's are overkill.
You're absolutely right. He could run it on just two 1.5v batteries and it would be weeks before those 3 LEDs ran the batteries dead. Personally, I'd use at least 5 ultrabright white LEDs for this and run it off of perhaps 4 AA batteries. This would produce a very bright flashlight and last awhile.
LasVegas8 years ago
There's a major flaw with your battery wiring. Basically you're wiring one battery backward to cancel out one of the others to acquire 9v in the end. You might as well use only one 9v battery. It would be better to connect all three 9v batteries in parallel with all negatives (blacks) together and all positives (reds) together. Better yet, for extended life, you could wire 6 AA Batteries in series (end to end) to acquire 9v.
robodud3 (author)  LasVegas8 years ago
i think i did i wired the negitive lead of the first batt to the negitve lead in the middle batt and that batts positive lead to positive lead in the last one
Yes, you did. But this wiring is not correct. There are two ways of wiring three batteries, depending on what your goal is. Parallel will give you the same voltage, but three times the available power. Series will give you three times the voltage, but the same available power (actually that of the weakest battery). See drawing:
Picture 2.png
Ian01 LasVegas8 years ago
Not power. Current. The available power is the same. Remember the power equation, P = E x I, where P is power, E is EMF (voltage), and I is intensity (current). Wiring batteries in series adds their voltage, and wiring them in parallel adds their current and also capacity. Alkaline 9V (PP3) batteries have a capacity of 565 mAh (milliamp-hours). If you wire two in parallel, the capacity will be 1130 mAh.
LasVegas Ian018 years ago
Not Current, but Amp-hours... They are not the same. One indicates the speed in which the electricity moves through the wire and the other refers to available power of a power source. You're arguing semantics here. I was not referring to Power in Watts, but to power, a layman's term referring to available supply from the batteries, IE: mAh's.
Ian01 LasVegas8 years ago
If you wire batteries in parallel, you can draw more current from them, right? I know the difference between current and capacity (mAh), I thought I was making myself clear.
LasVegas Ian018 years ago
Yes. But you still only get the capacity of the weakest member. This was my original point. I was not referring to Wattage (P=IE), but to capacity(aka "available power").
Ian01 LasVegas8 years ago
According to this FAQ, wiring batteries in parallel increases the capacity.
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