granules to filament? hopper?

I have a real hard time in getting the filament. Even harder to get PLA.

I found a lot of merchant selling them in granules, which could be ordered in much affordable quantity. For 3mm ABS filament form, the min order is like 50 to 100kg.

Even worse, I have yet to found anyone who will make PLA filament!

I heard some people were working on hopper extruder? Is there any update to that?

I also have an idea that instead of extruding directly from the granules, why not making a filament from the granules, and then feed the filament to an ordinary extruder? That way we will create some buffer so that the hopper filament speed need not to be an exact match could run at slightly different speed than the extruder.

Thoughts? Is there any chance that I could push granules into 3mm filament? Does anyone see any major roadblock with this plan?

oh. I finally digged out some older post and blogs. Look like we are still far from success.

The nearest thread I found is [dev.forums.reprap.org]

I doubt if the recent "breakthrough" findings of stainless steel barrel and thermal barrier can be applied here or not. Hm...

Yup, a granule feeder is one of things that is on the todo list, along with,
multiple heads
Auto head changing
Supporting a head that extrudes a support material

Though even with the idea in my head for auto head changing, it can't support a granule feeder, its just going to be too big.

Though, i'd like to throw to you an idea, and maybe you could design a hopper extruder based on that.

Coach Screw


I've seen these a few times at the hardware store, and in my head it could possibly be used for a granule feeder, with it geared down to get a higher torque to force the plastic through better, may work.

And a paintball hopper so it can feed the extruder


Edited 1 time(s). Last edit at 09/08/2009 04:48AM by Grogyan.

I've heard of small injector molding machines being build from hydraulics out of a door closer. I think that you could probably extrude filament with equipment of this type, but I don't know what kind of width precision you would get.

I've been doing a little research into some work at home on small quanity filament extrusion. I think a modified Gingery press would be best. While the base design (metal block, 2 cartridge heaters, die, and piston) is fine, it also requires significant machine shop hardware to get the piston drilled and reamed accurately.

I was thinking that a design made out of a long steel pipe nipple would work well. The die end would be a union used to clamp a steel circle in place that has had a hole drilled in it off-side. The nipple should be sanded/polished smooth on the inside, probably with a drill "flapper" sander. The major issue would be the piston end, a raw bit of steel or aluminum bar that's turned down to fit would be best. If it's thick enough, a rod could be threaded partially through the center and the disk spun and a file used to sand it down to size. The pipe would have to be wrapped in Nichrome wire and insulated. The nipple could be used to hold the whole thing via a steel ring (beaker ring from a surplus lab supply house). Put in the plastic, cap it off, start heating. You may want to use a thermocouple or PTC to PID temperature control the unit (I don't know if the extruder controller would hav enough oomph for this). It would take a LOT more power than an extruder head. Now, the simple way to press the plunger is actually a C clamp. With an off-center hole on the plate, we won't be blocking it. the clamp would provide a handle to support the contraption and an Acme screw to push down with. If we extrude into a water vat, it just might work.

I haven't done heat calcs yet, which might doom this idea. Volume calcs for a 2" dia x6" US steel pipe nipple result in theoretically 23m of filament per "shot" at 50% pipe fill. That's 170g of plastic.

Any progress with the Filament Extruder, especially that described by SOI Sentinel? I am interested and would like to get involved.

worm gears would work well as an auger for a hopper as they have large threads and are made to be attached to motors

Hello community!

There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine

I would like to notify you about my project, which is partially bases on research such as this forum topic and other simultanious projects:

My PROJECT PAGE
My FORUM TOPIC to give feedback after examining the project page obove

similar simultaniuos projects:
Marcus grinder/shredder+filament maker project
extruder printer head Project page
extruder printer head Topic page
Filabot project
you can also see my project page to see all the links and projects I've found on my research. It can save you time to follow my notes.

Greetings Ward

PLEASE CHECK MY EXPERIMENTAL EXTRUDER

AT

[www.thingiverse.com]

Nice Plastic Extruder on Kickstarter.
The project seems a big success looking at founds.
It creates filament from granules.

We are not yet to RepRap using granules, but the direction seems that.

I was looking for something similar recently and came across this kickstarter. I think it's finished but it may be something to watch for later on...
[www.kickstarter.com]

ugotdan Wrote:
-------------------------------------------------------
> I was looking for something similar recently and
> came across this kickstarter. I think it's
> finished but it may be something to watch for
> later on...
> [www.kickstarter.com]
> struder-a-robust-inexpensive-filament-extruder


That's mine! We plan to sell after shipping all the backer rewards - just email filastruder@gmail.com to get on the waitlist.