You can use this Hobbing Jig to get nice evenly spaced cuts when making a hobbed bolt.

I had trouble with some new ABS which had trouble feeding through my extruder. The ABS was a bit thinner (2.7mm) instead of the normal (2.85mm). It was also a lot softer than my imported stock. But because it was locally made, and about half the price of imported ABS, I really wanted it to work. So I set out to make a new hobbolt, which still works in my old extruder, but give better grip.

Then I saw this thing by Elk called "Transport screw workaround for wade extruder". (http://www.thingiverse.com/thing:9291) I tried it, and it works great! But I thought, to get a bit better precision, I need to make a jig. So my Hobbing Jig were born.