I’m attempting to gauge the interest level of a Universal Pellet Extruder from everyone and anyone who would like to see an Open-source 3D printable design.
Tagging in -
@Sanjay_Mortimer1 @Whosa_whatsis @Jason_Gullickson @Florian_Horsch_flouS as I may need some help from you guys 
Originally shared by Richard Horne
Would anyone like to discuss Pellet / Granular extruders? I ask because I have been working on various designs for quite some time with success and also plenty of failures , it’s not easy, it needs collaboration and I would like to see it stay open-source and accessible to all at a very low cost.
If people are interested I’ll post more about where my development is at and my designs for a Universal Pellet Extruder for 3D printing.
Let me know - Rich.
http://www.youtube.com/watch?v=nW4kmJAypZM
This would be interesting. One drawback I’ve always wondered about is changing materials/colors; it’s easy to pull filament out.
A) What are the non-printable costs? B) What are the costs to create the filament? C) How do the costs compare to a $20 1kg Roll of filament?
I’m curious to see just how cheap filament gets once enough companies compete and ramp up. Sure, there’s an appeal to making the right amount of filament, dry, when you need it, but there’s the added space and effort to do so. There’s a certain convenience to ordering the stuff online (or running to Microcenter, Lowes, Home Depot, Radio Shack in the future) and having it just take up the space of a spool.
Still, high quality, uniform extrusion that isn’t 4" in diameter and brittle has it’s benefits, too.
@Mike_Miller
From what I’m seeing, this idea doesn’t use filament; it goes straight from pellets to print.
I would be very interested in an extruder that could print pellets and shredded scrap with a consistent flow rate.
I once made a calculation for the filastruder…the result was, that I would need to make 16 kg of prints before the filastrooder would start to pay off…and I calculated with stable filament prices here, but I’d expect them to drop.
Awesome @Richard_Horne - this is really the way to go. Filament extruders get better and better, pellets are more available these days, it’s definitely possible (as current Kickstarter projects show) so it’s a good time to push this a bit. Especially when looking at all those XXL printers (yours, Delta Tower XL, the Japanese monster, the one from @seemecnc , KamerMaker by @Joris_van_Tubergen & Co.).
It’s just not clever to use 3mm filament when filling humongous build volumes.
Let me know how I can help! I have some experience with filament extrusion, some special pellets laying around, access to high-quality masterbatches and printers en masse to test with.
Tim here, from Filastruder. Happy to share the experience I’ve gained developing the Filastruder over the past 18 months. I have a lot of reservations about the feasibility of pellets -> print without filament in the middle for small, detailed models, but there’s no reason it wouldn’t work for larger (like a basketball or bigger) prints.
@Tim_Elmore1 Agree - good for big printers like 2 feet square and up, questionable for the average 6x6x6 or 8x8x8 hobby printer. With big printers and big nozzles, it’d be hard to keep up with filament loading.
@Clint_O_Connor & @Tim_Elmore1 agreed. But you definitely saw the @Sculptify campaign where they’re not focused on huge prints: https://www.kickstarter.com/projects/sculptify/david-the-next-step-in-3d-printing
Well, the quality isn’t on the level of proper FDM printers yet, but @Slade_Simpson and his team will get it up over the development process I guess.
#exciting
Richard I think its a great idea,I live in Australia and we get gouged here, we can expect to pay 20% and more than what other countries pay, for no other reason than its just been that way. I do not think we will see any benefits from competition here reducing consumables costs like going to pellets would be wonderful regardless of printer size. go for it !!!
Always a fascinating process to see you emerge with a new addition to the 3DP world!
Direct use of pellets has some interesting properties, especially if you can mix colors for custom colors, they add a new mechanical to the process which is material feed, the existing filament uses the structure of the filament itself to enable it to feed from spool to extruder, whereas a pellet system would need a conveyor/hopper or something.
The challenge of filament feed is a lot simpler to address (and thus I believe less expensive and more reliable).
@Carlton_Dodd No, you just send it through, purge it out or let it mix with the next material/ colour, hoper is small and can be constantly refilled - automatically by a mechanical system if required.
@Mike_Miller it’s all low cost to make the extruder - and it’s using the pellets directly, not making filament, that just takes too long to do at home. Raw pellets are between $2.50/kg for PET $3/kg for ABS and $4 for PLA
@Daniel_Wood That’s exactly the goal that got me started on this development, Recycle, Reduce, Reuse 
I’ve never understood the comments about at home extruders taking too long. They’re faster than the fastest filament based printers I’ve come across! Printer on, 'struder on. Endless filament.
@Florian_Horsch_flouS Thanks for your support, your help and advice is so much appreciated.
I’m also long time fan of the Kamermaker, that was actually one inspiration for seeing if it could also be done for desktop 3D printers I started with a ‘Bowden pellet system’ it was a total disaster!
I did also reach out to Sculptify on Twitter the other day, but they didn’t get back to me 
so that was the turning point to get more people involved with this project.
@Tim_Elmore1 Thank you, that would be fantastic, I have a lot of questions based around particle size v augor size and shape, what works well for one is not ideal for another shape and size of pellet. that’s a problem.
Generally the flight depth has to be at least 1.5-2x the maximum pellet dimension for good feeding. Less than 1.5x and it starts getting dicey. Solid center screws are stronger, but can’t feed as large of pellets for a given diameter. Unfortunately custom screws are probably out of the target price range for this (they are out of budget for Filastruder). Bigger screws feed better, but require more torque. I’d probably aim for a 1/2" screw in this case, especially since you look to be floodfilling. Filastruder uses a 5/8" but can afford to have a larger motor since it doesn’t have to move. Total weight of a Filastruder is 8lbs.