Your neighbors are going to love you if you start filling up the back yard with foam at your next party. It’s an easy enough build, but depending on your ability to source the major components it could cost a pretty penny to use it at your next rager.
[Species287] used a big fan and water pump which he already had on hand. All together that saved him about $200 (he’s pricing in Australian Dollars but they’re almost even right now with USD). The soap solution is super cheap, just a bottle of dish washing liquid mixed to the correct proportions with water, but you’ll need a way to apply it to the fan. Some irrigation supplies connected to the fan grate with zip ties did the trick. The pump is submerged in the bubble liquid, causing it to spray from the nozzles near the fan. But this won’t actually create bubbles. The last piece is a bag-shaped hunk of shade cloth from the garden store. Each pore of the cloth acts as a bubble ring. The cloth gets sprayed with soap by the sprinklers and the air from the fan then blows the bubbles.
There’s no video of this project so if you want to see it in action this other diy foam cannon will have to do.