I was walking through my local camping supply store the other day when I came across this water purifier that cost $50 (I know outrageous) Being the DIYer I am I took a closer look at it to find that it was simply Some UV lights. Then it hit me, I can make this way cheaper. So I did.
HINT: start your soldering iron and hot glue gun now so they warm up
Step 1: What You Will Need
Here is a list of all the tools and parts you will need.
- some ultraviolet LEDs, I used 4
-A small switch
-One resistor for each LED, Mine were 330 ohm
-Black tape/ Electrical tape
-Small plastic or glass container, This should be watertight and clear
-A battery, Mine was a 7.2 volt RC car battery
-Wire cutters/ strippers
-Hot glue gun with hot glue
I had some stuff but I had to buy the LEDs ($2 Each) and the switch ($1 for a pack of 5)
Step 2: WARNING
This is from the label on the bag that the UV LEDs came in.
"This LED produces intense ultraviolet light. Exposure to UV radiation can be harmful. Protect your eyes and skin when operating. Never look directly at the LED. Buyer assumes all risks using this LED."
Just so you know and don't try and hold me responsible either.
Step 3: Soldering Part 1
Now that you have everything Get out the soldering Iron and solder each resistor to each anode of your LEDs (anodes are usually the longer terminals)
Then wrap them in electrical tape.
Step 4: Soldering Part 2
Now solder all your cathodes together (the shorter end)
And solder your anodes together on the other side of the resistor.
then solder a wire onto each and wrap in electrical tape.
Step 5: Solder on the Switch (part 3 of Soldering)
Now onto the anode wire solder a little switch on. and solder a little more wire onto the other end of the switch.
And just in case you haven't caught on wrap your connections in electrical tape
I used a momentary switch because UV lights are dangerous and I would not want it to accidentally turn on and stay on.
Step 6: Time for the Container!
Now take that small little clear container and put your LEDs in while leaving the switch on the outside.
To get good results bend the heads of your LEDs to make sure that they make an even spread of light.
because i do not have plans to fully submerge my container I just made the top of it water resistant by sealing it with tape and hot glue.
Step 7: Hook It Up to a Power Source
I tried using a smaller battery for this but none seemed to prove themselves worthy so I Ended up using a 7.2 volt Nickel Cadmium R/C car battery.
It was fairly easy to connect but I did not solder direct to the battery because I NEVER do that no matter how much wire is in between. its just dangerous.
Step 8: Operation
To use it simply expose by partially submerging the UV LEDs to your water for about 30 seconds and your water should be good and 99.99% bacteria free.
Thanks for reading.
EDIT: ok so it turns out that the LEDs I got are not quite powerful enough but this still gives you the basic concept. I would recomend that you get some 240nM UV LEDs they will raise the budget but it is worth it.
EDIT: (3/1/15) I made this several