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29Apr/12Off

Hobbed bar, hyena v1.0

This is my take of a new hobbed bolt replacement :)

I call it the hyena, because hyenas have the strongest jaw of all mammals.
All teeth are cut individually:

Here is a comparison photo with one of my hobbed bolts:

The brass one is the new version:)
You mount it with a M8 nylock nut, so the width of your extruder does not matter.

Key advantage over the old version

  • It's machined from straight, round brass stock. Regular bolts often have large tolerances and are not entirely straight. The hyena is guaranteed to be straight.
  • Each tooth is individually machines, so there is no "orphan tooth". An orphan tooth is an incompletely cut tooth that occurs during hobbed bolt production with a tap, because the teeth of the tap do not match the diameter of the bolt while cutting. This is a problems because it's the spot where filament begins to slip. It tends to bite a small piece of plastic off the filament as it does not reach deep enough to grip. The next (normal) tooth continues eating into the filament, resulting a complete filament strip, and no printing. The hyena prevents this by making sure every tooth grips by the same amount.

Installing on a Wade style extruder

Some pictures, from the top:

Also when opened (please note the washers around the bearings!):

(Also take note the really useful and special M8 nut. It will be the subject of an another announcement:)

Im a technical guy, any drawings?

Here it is:

Enough talk, I want one!