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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!


Guest article: Tiny’s first experience with Hotend v3.0

It was announced as "really big", but is the Hot-end v3.0 is that great?


Blender broke – Epilogue

My article titled "Blender broke" drew more media attention, than anything I've written lately. This is strange, as much cooler things have been happening around me:) Many sites picked it up.

I later read on a forum (I've forgotten which one), that the printed replacement part will break as it could not possibly be as strong as the original one. That did had some truth to it...



When a compiler reach the state, when it can compiles itself, it's called self-hosting.
My Hot-end v3.0 reached that state, and more:-)

30Oct/10Off Hotend v3.0 dummy model

This is a dummy model of Hot-end v3.0 to get a feeling of the actual size. A real hot-end cant be printed using plastic:)