It’s getting hot again in California.
I survived last summer’s brutal heat by leaving the state altogether for a little while; I’m not going to be able to get away with that this time, and not having AC in the daily driver has me in for a miserable time if I don’t do something soon.
The old window mounted swamp coolers pop up regularly at swap meets and ebay, but they’re carrying a pretty steep price tag, usually around $600 for a restored one, or $300-$400 if you’re willing to put in a little work. Trawling decade old forums turns up some sort of reproduction that was made for a while but it’s a lot of dead links. They aren’t complicated devices, though, and there’s a few DIY articles out there making them out of old fire extinguishers, but I have some 6″ aluminum pipe laying around and figure I might be able to 3D print a few parts and make something that works just as well and learn a little bit along the way.
These swamp coolers work by taking air in the front as the car moves, send that air past a wet mesh, and into the cabin of the car through a passenger window. The water absorbs energy from the moving air to evaporate, cooling down the air as it passes through. Old style models had the mesh around a cylinder that could rotate when a string is pulled, to re-wet the surface. I’m hoping to add a mechanism to automatically turn this cylinder, either through some sort of fan, or a small solar motor.
The 6″ works well because I can print the front and end caps for the pipe on the Maker Select printer that I’m running – a 7″ square is about the biggest I can do. The main body will be about 20″ long. The I also want to keep things light and simple, and cutting up the pipe like some of the DIY articles might kill some pipe integrity, so I’m sticking to just using a small hole saw to ventilate the pip. These holes can be seen in the concept image at the top of this article. A small modular manifold will direct the air into the cabin, and act as a bracket to hold the swamp cooler to the door. The inner cylinder will be roughly 4″ diameter, using a light aluminum mesh, wrapped with scotch brite or cheesecloth. The cylinder will rotate around a central shaft using skateboard truck bearings.
I hope to have a working prototype a few weeks.
Project Evap and Chill.
