The basic idea for the bucket cooler is just a smaller version of Yellowdog's cooler made from a rubbermade garbage can.
An evaporative cooler will reduce the tempature by 20 to 30 degrees.
Keep in mind that there is more than one way to skin a cat. (WARNING! DO NOT SKIN A CAT, IT WONT HELP THIS PROJECT AND WILL IRRITATE YOUR PUSSY!!!)
All the ideas that people came up with on this thread are a perfect example of radical self relience! (Bravo!!!)
Get a 5 gallon bucket and lid.
Have your trained mice naw some holes in the bucket, or use a hole saw, or 50 caliber sniper rifle. (Honey badgers wont work, they don't give a shit!)
Find some cooler pad.
I like duracool pads.http://www.simsupply.com/Items/426741
If your area does'nt have them, find a national chain DIY hardwear store and see if they will order some for you.
This may save you shipping cost. I use home depot.
Cut the first pad 33 1/2x13 inches.
Roll this pad into a tube and silicone or hand stitch the seam.
This will give you a tube 13 inches tall.
Because the bucket tapers out towards the top, you will not need to line the bucket with shade clothe.
Cut a second piece of pad 24x13 inches and roll into a tight tube.
You wont need to seam this one.
Sleeve this inside the first tube.
The reason for the double pad is to have a wide space to set the drip line on and adds more evap surface.
1/2 inch Drip irrigation line works ok to soak your pads, but poly hose is more flexible and you can buy it by the foot.
I like the T connectors that fit inside the line. I cut the ends of the T shorter so I could keep the holes in the line close enough together so there wont be a dry strip on the pads.
This hose is 3/8 inch.
The holes in the line need to be uniform for an even flow on the pad.
Drlling holes works, but I found that heating a piece of wire melts a nice, more uniform hole.
I used a piece of 10 gauge copper wire.
Heat the wire with a torch, or the burner on your stove, then press through the line.
Sliding the wire in and out till it cools will make a happy hole! (Don't even think about it Yggy, this is serious!)
To pump the water through the line, buy a pump.
This is the solar pump.http://www.harborfreight.com/solar-powered-fountain-pump-66093.html
I like this pump instead because if it's cloudy, it will still let the cooler work.http://www.ebay.com/itm/12VOLT-DC-SUBMERSIBLE-WATER-FOUNTAIN-PUMP-FOR-USE-W-12V-SOLAR-PANEL-OR-BATTERY-/400297468468?pt=LH_DefaultDomain_0&hash=item5d3396a234
The 3/8 inch line fits this pump perfectly.
Nice even flow of water.
When the lid is put on, the line will be pinched between the lid and the pad, so it wont move around.
The key to a good cooler is a powerful fan.
CFM=cubic feet per minute.http://www.frozencpu.com/cat/l2/g36/c435/list/p1/Fans-12_Volt_Fans_by_CFM.html
I used this one.http://www.frozencpu.com/products/8556/fan-533/Delta_120_x_38mm_High-Speed_Fan_-_19048_CFM_AFB1212SHE-CF00.html?tl=g36c435s1108&id=YnFfDVU7
It uses more power, but makes the bucket cooler very effective.
Calculate the cubic footage of the space to be cooled, then get a fan that will replace the air inside the space every 3 to 5 minutes.
I use a single fan cause it suits my design perfectly.
Cut a hole in the lid of the bucket to mount the fan.
I put mine on the bottom of the lid to keep the unit compact and to make ducting easier.
Any 120mm fan will fit inside the top of the pad tube.
I spliced the wires from the fan to the wires from the pump. (both are 12volt)
Then ran the wire out through one of the holes in the side of the bucket.
Now with the lid on the bucket, I used a 4 inch septic line connector gooped to the lid over the fan.
Now you can use 4 inch septic line to duct the air into the space to be cooled. You don't need to glue these piceces together.
These parts are at the hardwear store.
Air temp coming from the cooler!
Water temp inside the bucket!
This cooler uses 2 gallon of water every 5 hours.
It uses about 1.45amps per hour.
My 105AH deep cycle battery will run this cooler for 47 hours before needing to be recharged.
So running 4 or 5 hours a day, it will let you nap in the hottest part of the day, all week without recharging the battery.
If you need more cooling than this, build the box cooler.
You will need to vent the air out of the space for circulation.