Daniel,
> On Jan 26, 2015, at 12:18 AM, Manchala, Daniel <Daniel.Manchala at xerox.com> wrote:
>> I am not an expert in 3D printing but the following sentence seemed a little confusing:
>> 3.2.3 Filament Feed Jam
> While printing a 3D object, the filament jams and cannot be fed into the extruder.
>> I thought a filament jams the extruder and hence cannot be fed 'through' the extruder rather than 'into' the extruder. This is where I got information on extruder jams from:
>>https://www.matterhackers.com/articles/how-to-clear-and-prevent-jams
We can debate wording at the F2F, and I'll probably want to add some figures showing the different subunits and different implementations. One of the issues we will need to address is clearly defining terminology and functional components. There is a lot of non-authoritative information online about 3D printers and very little standardization of terminology, partly due to the relative immaturity of the technology and partly because there are so many enthusiasts trying different things right now.
For filament jams, I am referring to a jam in the feed of the filament from the source (typically a spool) to the hot end (the actual extruder) and not specifically the drive mechanism which can be located at any point leading up to the hot end. Most jams happen inside the Bowden Tube (for printers that use them), but it is also possible to jam at the point of entry to the hot end or even in the drive mechanism depending on the design and the print settings. Perhaps a (helpful?) ASCII art diagram showing a few common designs?
|vvvvvvvvvvvv FILAMENT PATH vvvvvvvvvvvv| |EXTRUDER|
SPOOL ----> DRIVE ----> BOWDEN TUBE -----> HOT END -----> PLATFORM
SPOOL ----> BOWDEN TUBE ----> DRIVE -----> HOT END -----> PLATFORM
SPOOL ----------------------> DRIVE -----> HOT END -----> PLATFORM
|^^^^^^^^^^^^ FILAMENT JAMS ^^^^^^^^^^^^| | CLOGS |
I am also thinking about extruded food printers, since there the source material is either liquid or melted and then pumped through the extruder head. By separating the feed/input from the place where the material comes out in a different form, we can provide fairly specific feedback/status information in a logical way.
So, a filament can be jammed only as long as it is filament (solid). Once melted, it can only get clogged. (or at least that's how I am looking at it...)
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Michael Sweet, Senior Printing System Engineer, PWG Chair