[Ben Krasnow]’s Take On DIY Air Bearings

We’ve got to admit that watching¬†[Ben Krasnow]’s new video on air bearings is tough. We found our eyes constantly checking the spherical air bearing in the foreground, which for the first eight minutes of the video just kept going. It was strangely hypnotic, and made it hard to concentrate on all the other cool stuff [Ben] was up to.

If the topic of air bearings seems familiar, it might be because we recently reported on DIY air bearings made from used EDM electrodes. [Ben] saw that too, and dusted off his old air bearing project. Literally, as it turns out, because the graphite blocks whose porosity and softness make them the perfect material for air bearings also makes for a dusty workshop. We’d recommend breathing protection of some sort while machining graphite.¬†In addition to simple puck bearings, [Ben] came up with more complicated designs, including the aforementioned spherical bearing. He used the steel ball itself as a precision tool to grind the graphite out, first by coating it with abrasive and then by cutting grooves in it to act like a file. A cylindrical bearing was also cut, this time with sandpaper glued directly to the ground steel rod that would seat in the bearing.

[Ben]’s other innovation is vacuum preloading, where he applies both vacuum and pressure to the bearing plenum. The vacuum provides the force needed to capture the moving element while the pressure bears the load. It’s a careful balancing act, but it works well enough to capture the large steel ball and keep it turning effortlessly.

We really liked [Ben]’s take on air bearings, especially his thoughts on creating fully enclosed cylindrical bearings. Those could be useful for low-friction linear drives, and we look forward to seeing more on those.

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Gizmodo’s Guide To Smartphone OSes

Gizmodo’s in-depth look at smartphone OSes provides you with the pros and cons of each, allowing you to make an educated decision, if you’re in the market for a phone that also has email, a web browser, a calendar, and a decent contacts manager. If you’re attracted to the open source Linux-based Android by Google, you’ll also have to keep in mind that there aren’t that many business features. Other contenders include the Blackberry by RIM, which is great for email, but is completely closed and proprietary. The Apple iPhone is very pretty but lacks some basic features. They cover Symbian, Windows Mobile, and Palm Garnet too. It’s certainly a handy guide since most people haven’t used all six.