Since I have been having foamy beer with a tower, I have been looking for guides/internet instructions on how to build a blower with a computer fan. I wanted to put in my two cents for how I built mine and where I got the parts. Sorry I do not have any pictures but in case this helps anyone in the same situation. I have a Sanyo 4912 that I had to cool the tower
I started with the small project box at Radio Shack. It was the 4.99 one since I wanted to save space.
I then purchased an Antec 12V DC fan from Staples that had adjustable speeds of low medium high. It was 80mm and costs 9.99.
I purchased a DC adapter from Radio Shack that was 20.99 This was an AC to DC adapter and had volt selections of 3,7,12, and 13. I did not have that cell phone adapter to use.
I purchased some vinyl tubing at Home Depot 10 ft 1/2 diameter for 3.88.
I first cut out a small hole in the project box because I did not have a 3in hole saw. I then measured out a circle around the fan and cut that out using a dremel tule.
I then placed the screws through the plastic to line up the holes for the fan.
I then proceeded to cut out a small hole for the 1/2 tubing. I placed the holes for the tubing at the top of the project box.
I then cut out a small indent between where the two project boxes connect with a saw for the power cabling for the fan. Make sure this is small so no air can escape.
I then cut off the two ends of the DC Adapter and the Fan Adapter. I combined them and soldered them. I then placed electric tape over them.
Keep the DC adapter at 12v and the fan at high setting. I then put it in the refrigerator and used some tape to make sure it stood up. I cut the tubing down so that it was a few inches below the top of the tower and voila.
I ran the power cord out the front of the fridge due to how thin it was.
Hopefully it helps someone and sorry for no pictures.