Printable linear bearing
thingiverse
Inspired by the above thing, I wanted to try a linear bearing made using airsoft balls. http://reprap.org/wiki/Printable_linear_bearing The linear-2.2 (same has 2.1 but closed) have a bit of friction (because the balls don't make a loop) but it works (25mm long x 23,41mm ext diam) Video : http://youtu.be/GTtfGQe4o7o Instructions You can either put the balls inside while it's printing, or after with a plier, pressing gently to push them inside.
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