How in the world did the screen door design, with the little crappy nylon wheels on the W-shaped spring manage to dominate the market for so long? As far as I know, they're still made this way. The tracks get clogged with insects, dirt, wasp's nest, and other detritus, the wheels jam and break, the springs rust and are hard to remove and replace (despite the glib instructions on the replacement package), and to put it bluntly, the design sucks. I can't come up with a better one myself without more thought than I want to put into it, but annoying design problems like this ought to be put as challenges to engineering students, and the winning designs open-sourced to the world.
last updated 2011-07-28 22:30:39. served from tektonic.jcomeau.com