626

Re: Filament Extruder - Convert pellets to filament

Several designs for filament machines I've looked at use auger-style drill-bits as the screw.

An actual proper extrusion screw (as seen in huge extrusion lines and also injection molding machines) has a distinct profile to it.

The most efficient design (winning design if you will) of these home extruders will be the one that contains a properly profiled screw.  This will reduce energy consumption, as you won't have to run nearly as hot as (for example) the Lyman design does.


Second,  most large lines have a pull-system.    Basically the material is pushed from the die at the same time it is PULLED down-stream.   The ratio of push-to-pull is called draw... and by altering your draw ratio you can improve quality drastically.  No more variation in filament size for example.  Simple knurled rollers with a varispeed drive would work great for this.


If I had the money I could sit down and build such a device at the community metal-working shop at the Vo-Ed highschool.   That won't be for awhile.. I'd rather get the idea out there and see what others can do with it rather than keep it locked up.

627

Re: Filament Extruder - Convert pellets to filament

I got a quote from the following auger company and it was over $50.
That is to high for a hobby.
http://www.augersunlimited.com/Inventory.htm

Ultimaker S3.

628

Re: Filament Extruder - Convert pellets to filament

The beauty of the Lyman design is the off the shelf parts that you don't need a mortgage to pay for smile I could easily throw a 4th axis on my mill and make proper profile extrusion screws but at what cost? once you do that you also have to have a precision barrel for it to get the most out of it and work properly and more station heaters etc..$$$ The main problem I see is there are plenty of maker type people willing to spend a couple hundred bucks for a tool even if it's slow but once you jump to a couple thousand the number of people willing or able to spend the money on home grade equipment shrinks rapidly. With that said, ideas are always welcome and usually spur more ideas from differing views and sometime all it takes is one person thinking out loud to come up with a breakthrough in designing a really cheap product that works!!! smile

629

Re: Filament Extruder - Convert pellets to filament

Figured I'd toss the idea out there in the hopes that it inspires someone.    I am aware of the challenges in making a "proper" screw.   

Eventually someone will figure it out I have no doubt.

630

Re: Filament Extruder - Convert pellets to filament

dubbsd wrote:

I got a quote from the following auger company and it was over $50.
That is to high for a hobby.
http://www.augersunlimited.com/Inventory.htm

And that place doesn't seem to make the augers for plastic extrusion all I saw were regular flighted augers...

631

Re: Filament Extruder - Convert pellets to filament

I took my Filastruder to Deezmakers Sun, which is a nearby hackerspace/store where they produce the Bukobot.  A couple posts and a video are up at Google+  https://plus.google.com/s/filastruder

Diego gave me a couple of cartridge heaters to try out.  I could lash them on with Kapton, which wouldn't be very efficient but worth a try.  It would let the whole thing run on 12v.  He suggested using the CNC there to make an aluminum heating block with a couple of holes drilled out for the cartridges.  It might heat a lot faster, you could add a hole for a second thermocouple at the heat source, and control it from the Arduino that will be running the puller.

I'm putting together a Wade's extruder which I can mount sideways to pull the filament through to the spool.  I modified it to make room for a roller rather than a hobbed bolt.  I have it hooked up to an Arduino Uno, and figured out how to use a rotary encoder to dial the speed of the motor up and down.  I bought a Panelolu kit and never put it together, so I can rob the LCD from that as well later on.

632

Re: Filament Extruder - Convert pellets to filament

IanJohnson wrote:

I took my Filastruder to Deezmakers Sun, which is a nearby hackerspace/store where they produce the Bukobot.  A couple posts and a video are up at Google+  https://plus.google.com/s/filastruder

Diego gave me a couple of cartridge heaters to try out.  I could lash them on with Kapton, which wouldn't be very efficient but worth a try.  It would let the whole thing run on 12v.  He suggested using the CNC there to make an aluminum heating block with a couple of holes drilled out for the cartridges.  It might heat a lot faster, you could add a hole for a second thermocouple at the heat source, and control it from the Arduino that will be running the puller.

I'm putting together a Wade's extruder which I can mount sideways to pull the filament through to the spool.  I modified it to make room for a roller rather than a hobbed bolt.  I have it hooked up to an Arduino Uno, and figured out how to use a rotary encoder to dial the speed of the motor up and down.  I bought a Panelolu kit and never put it together, so I can rob the LCD from that as well later on.

I've been using 100 watt band heaters so far. I thought about using the cartridge heaters- couple issues:

1.) You'd then need a 125watt 12v power supply. Good quality supplies (like Meanwell, etc) for this run ~$30 used.
2.) You'd then need either an Arduino, or still need the same PID controller for the control of the heater. You'd need to switch 10 amps instead of 0.9.
3.) You'd need an aluminum or similar block to mount the cartridge heaters in.
4.) It won't heat faster, unless you go up in wattage. If heating faster is what you guys want, there are more powerful band heaters - but you still have to wait for the plastic at the center of the pip to heat up, without cooking the plastic at the outside of the pipe. That limits the heat flux you can push.

Excited to hear how the puller/spooler work out!

633 (edited by elmoret 2013-02-06 06:28:11)

Re: Filament Extruder - Convert pellets to filament

Got some black pellets in today!

https://dl.dropbox.com/u/1786359/Photo%20Feb%2005%2C%2011%2029%2010%20PM.jpg

Took about 10 feet to go from natural to black. Seems to extrude nicely. Speaking of results, I set up this google doc:

https://docs.google.com/spreadsheet/ccc … sp=sharing


It should be editable by anyone. If you could, post your results there. Thanks!

EDIT:
10kg total - black, grey, clear, and natural, all of it filastruded!

https://dl.dropbox.com/u/1786359/Photo%20Feb%2006%2C%201%2022%2019%20AM.jpg

634

Re: Filament Extruder - Convert pellets to filament

Great work!  It's hard to hold my breath for the release!

635

Re: Filament Extruder - Convert pellets to filament

elmoret, how much you want for a 1kg ish roll of clear?  I can't find a good source, and 3dprintergear is at $80+ shipped to Chicago area.  PM me if you're interested in selling some.

636 (edited by elmoret 2013-02-10 00:53:42)

Re: Filament Extruder - Convert pellets to filament

cmetzel wrote:

elmoret, how much you want for a 1kg ish roll of clear?  I can't find a good source, and 3dprintergear is at $80+ shipped to Chicago area.  PM me if you're interested in selling some.

Extruding now! Black for a bit, then clear:

637

Re: Filament Extruder - Convert pellets to filament

Very cool! Thanks for the stream smile

I have a feeling this is going to create a whole new business for people at home to extrude filament for other printer users.

638

Re: Filament Extruder - Convert pellets to filament

Are you extruding through a bolt threaded into the nozzle?  It looks like there's something on the end there, and I can't make out what it is.

639 (edited by elmoret 2013-02-06 19:48:32)

Re: Filament Extruder - Convert pellets to filament

IanJohnson wrote:

Are you extruding through a bolt threaded into the nozzle?  It looks like there's something on the end there, and I can't make out what it is.

It's just a brass plug, I had to get it locally (from Lowes) because i'd exhausted my supply from mcmaster when I built that one. It's a little different shape from the McMaster ones.

640

Re: Filament Extruder - Convert pellets to filament

What happens when you mix the clear and black? can you get a consistent blend of colour with a random mix in the hopper?

641

Re: Filament Extruder - Convert pellets to filament

danny wrote:

What happens when you mix the clear and black? can you get a consistent blend of colour with a random mix in the hopper?

Well, it's looking like trying to paint over black paint with clear paint - taking a long time to flush out.

Considering DeParted has gotten consistent coloring with masterbatch, I'd say mixing two precolored sets of pellets should be no problem.

642

Re: Filament Extruder - Convert pellets to filament

Masterbatch is proving hard to get.  Makibox has a variety of pellet colors though, and I was thinking of getting the closest thing to red yellow and blue that they offer, to try mixing.  Since they aren't concentrated like masterbatch, you don't have the problem of mixing the pellets at 50:1 and hoping the distribution is consistent in such small batches.

643

Re: Filament Extruder - Convert pellets to filament

IanJohnson wrote:

Makibox

They quote monster lead times. Any idea if they have this stuff on hand?

644

Re: Filament Extruder - Convert pellets to filament

I'm skeptical about that.  They list the same lead times for filament, which they say they extrude themselves.  I don't know if ordering filament from them means they will get their Ramen extruder done, or if they have access to a pro one and a pelletizer.   Or they will wait for someone to place an order with them, at which point they will order from an extruder who has to schedule their job.  However it's done, they are the only ones offering pellets in colors other than brown black and clear.  Also no one else has PLA pellets of any kind, including the Desktop Factory people who had promised to supply them.

645

Re: Filament Extruder - Convert pellets to filament

Great feed, Can you provide some data please?
Distance from nozzle to center of fan, ext temp and location of thermocouple,
distance x,z to brass tube, distance x,z to edge of table, temp of filament as it (leaves the nozzle, touches the brass tube and touches the edge of the table.
I can not get mine to go for long periods of time with out the ramen effect. When my filament touches the floor it wiggles at the nozzle, when it changes curl direction it wiggles at the nozzle.
Thanks

646 (edited by elmoret 2013-02-07 00:43:16)

Re: Filament Extruder - Convert pellets to filament

See page 15:

http://www.soliforum.com/topic/557/fila … t/page/15/

Not sure how I'm supposed to measure the temperatures you requested, the filament is moving ~ 1cm/sec! IR thermometer would not be even close to accurate, thermocouple can't be held onto something moving that fast.

There's less chance of ramen at lower temps - try 170C or so.

647 (edited by elmoret 2013-02-07 00:47:03)

Re: Filament Extruder - Convert pellets to filament

cmetzel: here's your "clear":

https://dl.dropbox.com/u/1786359/Photo%20Feb%2006%2C%207%2041%2057%20PM.jpg

Lesson learned: black will stick around for a longggg time, at least this particular resin. There's some clear buried deep within that spool, but it never fully flushed the black out. It actually went back to black, right as it was ending Woops.

648 (edited by DePartedPrinter 2013-02-07 00:54:56)

Re: Filament Extruder - Convert pellets to filament

elmoret wrote:
danny wrote:

What happens when you mix the clear and black? can you get a consistent blend of colour with a random mix in the hopper?

Well, it's looking like trying to paint over black paint with clear paint - taking a long time to flush out.

Considering DeParted has gotten consistent coloring with masterbatch, I'd say mixing two precolored sets of pellets should be no problem.


That answers my question about flushing out black. Wow. Is it even flushed yet?

SD2 with E3D, SD Press, Form 1+
Filastruder
NYLON (taulman): http://www.soliforum.com/topic/466/nylon/

649

Re: Filament Extruder - Convert pellets to filament

thanks

650 (edited by DePartedPrinter 2013-02-07 01:00:38)

Re: Filament Extruder - Convert pellets to filament

IanJohnson wrote:

Masterbatch is proving hard to get.  Makibox has a variety of pellet colors though, and I was thinking of getting the closest thing to red yellow and blue that they offer, to try mixing.  Since they aren't concentrated like masterbatch, you don't have the problem of mixing the pellets at 50:1 and hoping the distribution is consistent in such small batches.

Open Source Printing was suppost to get some more colors of masterbatch. I told them they need to get the primary colors so that we can experiment.

SD2 with E3D, SD Press, Form 1+
Filastruder
NYLON (taulman): http://www.soliforum.com/topic/466/nylon/