3 years after building my first Figjam bucket cooler and I finally used it on playa. Weather this year did not reach 90 degrees. I had tried them out at various events and was always disappointed in their ability to be anything other than a spot cooler. But I wanted to try on a hexayurt, on playa - as that was what they were designed for.
I brought 3 bucket coolers: 1 that I built, 1 that a friend built and 1 that I picked up on craigslist from a fellow burner. I can tell you that none of them worked to cool a 6 foot stretch yurt. I can say without a doubt in my mind that the bucket design is lackluster. Is there an ideal state that you can get to where the bucket design works well? Almost certainly. But as we all know from the endless back and forth on this thread that the writeup is less engineering and more architectural. Simple problems like variances in bucket widths & heights in regional home depot locations means that an instruction like "Cut the first pad 30x13 inches." is not sufficient. Which is why people end up with pads too narrow or worse, touching the side walls and leaking water out the bucket. A quick google search shows that the current Homer bucket is 14.5 inches tall. Which is why my first duracool pad was wasted when, after cutting, I found that the instructions did not match my bucket size and my pad did not touch the top of the bucket. Which is another error prone aspect, pads tend to sag over time which means even if you cut it correctly the first time eventually your pad will no longer reach the top of your bucket which provides a much easier path for air to travel - avoiding water completely.
On the bright side I also built one based on the unicooler design using a slim trash can.
That design highlights some of the most ridiculous aspects of the bucket design. In particular the fact that the unicooler has a significantly smaller pad size (my version has just 1 11x14 pad) compared to the bucket cooler shows you that the bucket design can too easily suffer from dry spots. I'm covering more than half the surface area with the same water pump in my unicooler as compare to the bucket. That leaves far less room to screw up the hole spacing in your circular hose, or angle of the holes. Or air bubbles causing the water to not make it the full 30 inches around. The endless breeze fan provides SOO much air power that even without a somewhat functioning swamp cooler it can feel pretty amazing blowing across your body with just light misting. The tiny CPU fans in the swamp coolers are completely worthless if the cooling function is not operating at full speed.
In my opinion, the unicooler design is better documented and less prone to failure even by the best of engineers. The smaller pad size and significantly larger fan give users more leeway in implementation - something the writeup already requires. I went with the trash can design because water proofing a wooden box sounded hard, something this forum seemed to echo.
Normally I'd try to contribute an attempt to better document a working bucket based swamp cooler. But I don't think I can, I have made many variances and the best cooling I got in very low humidity was under 15 degrees difference.
I think the best part of Figjam's contributions, for me, is the knowledge I learned in trying. The Figjam unicooler that I built will return to playa next year, but the bucket coolers will not. My friend was sweating in the yurt while trying to nap mid day; while I pulled a blanket on because it was getting too cool with my unicooler.