One more thing I need for the extruder is the hobbed bolt. Somewhere on the internetz I’ve found an opinion (I don’t really remember where..) that hobbed bolt which teeth are cut from the threaded part of the M8 screw have even better grip than tapped one. So I got few M8 fully threaded screws, and constructed a tool for hobbing. It uses dremel flexible hose, and those thin cutting disks – 0,6 mm disks allow for a finer teeth to be cut.
Rotating disc that holds the screw have 20 holes – which are a match for a 6mm ball pushed against it by a spring. This way I could measure each step I’m cutting. And here is the final result – isn’t she a beauty?!
I also made a video while hobbing – a little bit shaky, but it’s hard to hold camera with one hand while cutting… …probably will have to get some stand in the future.