SoliForum - 3D Printing Community — Extruders that use pellets directly?

Re: Extruders that use pellets directly?

null@example.com (joachim) — Mon, 21 Dec 2015 08:22:52 +0000

That's perfect. I just send an Email to you through this forum about the extruder.

Re: Extruders that use pellets directly?

null@example.com (Billsrf) — Thu, 17 Dec 2015 15:03:04 +0000

Yes , I build these in my shop

Re: Extruders that use pellets directly?

null@example.com (joachim) — Thu, 17 Dec 2015 15:00:27 +0000

Hi Billsrf, A very interesting picture in your last post. The most proffesional built pellet/granule extruder I seen. Do you know where can I find more info about this extruder?

Re: Extruders that use pellets directly?

null@example.com (Billsrf) — Thu, 16 Jul 2015 11:13:06 +0000

elmoret wrote:

Claghorn wrote:
The best I can visualize is something like a filastruder with the output feeding directly into a bowden tube :-).
Stratasys holds a patent on that.
https://www.google.com/patents/US201003 … &cl=en

I hate to tell you that is a compounder for blending different types of filament. I'm not sure feeding a printer from a filament extruder is a patentable piece of equipment. it would fall under a natural process. Just my 2-Cents

Re: Extruders that use pellets directly?

null@example.com (Claghorn) — Thu, 29 Jan 2015 23:36:11 +0000

elmoret wrote:

Stratasys holds a patent on that.

Well, at least I visualized a patentable idea (though given some of the patents issued, that may not be much of a feat :-).

Re: Extruders that use pellets directly?

null@example.com (elmoret) — Thu, 29 Jan 2015 21:38:41 +0000

Claghorn wrote:

The best I can visualize is something like a filastruder with the output feeding directly into a bowden tube :-).

Stratasys holds a patent on that.

https://www.google.com/patents/US201003 … &cl=en

Re: Extruders that use pellets directly?

null@example.com (elmoret) — Thu, 29 Jan 2015 21:37:03 +0000

Pellet extrusion printing isn't going to replace filament printing for a number of reasons, primarily:
you can't retract well
you can't mix color well (with pellets, concentrated color pellets are used)
you can't meter the feed precisely (depending on how pellets pack into the auger, expect flowrate to vary +/-30% while printing)
pellet based will be heavier than filament based, and therefore slower
etc etc.

Re: Extruders that use pellets directly?

null@example.com (Claghorn) — Thu, 29 Jan 2015 14:48:18 +0000

Interesting. The RichRap design seems to use a drill bit as an auger - no trouble getting parts to try it out :-).

Re: Extruders that use pellets directly?

null@example.com (Jmtyra) — Thu, 29 Jan 2015 03:13:10 +0000

RichRap has a downloadable design for a 'universal pellet extruder' and a blog post with details:
(Edit: tried to post a link, but the forum said 'no way'...Google "RichRap Universal Pellet Extruder")

It's on my to-do list of things to try.

Re: Extruders that use pellets directly?

null@example.com (jagowilson) — Thu, 29 Jan 2015 02:40:19 +0000

There was one called Sculptify if I recall. The fundamental flaw with them is they have not effectively managed retraction yet.

Extruders that use pellets directly?

null@example.com (Claghorn) — Thu, 29 Jan 2015 01:35:04 +0000

I keep stumbling across articles about large form 3D printers that have special extruders that use pellets directly rather than filament, but I've never seen any details about how these extruders work (and all my google searches seem to be cluttered with 10,000,000 results for pages that want to sell me pellets :-).

Anyone have any pointers to details on one of these extruders? I'm just curious about how the heck they work. The best I can visualize is something like a filastruder with the output feeding directly into a bowden tube :-).