by hlyman, published

LYMAN FILAMENT EXTRUDER by hlyman Sep 17, 2012


The Lyman Filament Extruder is a machine that extrudes filament from pellets for use in a 3D Printer. It can extrude 1.75mm and 3mm filament with easy nozzle exchange. The material cost is about $250.

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Version 5 is still in development stage. If it works it will be published near the end of May on Thingiverse. I will not be making extruders for sale. Lulzbot may be but I can't verify that. I have a hard time keeping up with email relies so you will have to check on Thingiverse in the future.

Every version just gets better and better also more 3D printed parts for a more polished look. Please email me link for version 5 at [email protected] I would like to know if you are selling them or kits if so what would be the cost

V4 Extruder will be published in about two weeks as soon as I can get the docs done. I am working on V5 and will have that also published.

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This filament extruder has been entered in the DESKTOP FACTORY COMPETITION.

The attached PDF file is a Manual which includes Fabrication and Operational instructions, including BOM, tools, photo's and drawings.

See thing #30705 for the Lyman Filament Spool Winder. Click on hlyman for my things.

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Anisimov on Feb 24, 2014 said:

Hellow. I'm from Russia. You filment extruder is very intresting for me. I have read about new version 4. When it will be accessible for buying? What about extrusion speed 3.00/1.75 filament in this version? What does filament extruder v4 cost? Thank You.

hlyman on Feb 24, 2014 said:

V4 Extruder will be published in about two weeks as soon as I can get the docs done. I am working on V5 and will have that also published.

inv4der on Aug 27, 2013 said:

Hi I think you did a great job, at what rate does this machine exrudes filament?
Thanks a lot for your design...

hlyman on Aug 28, 2013 said:

About 8" peer minute. My new version 3 will extrude at 30" per minute.
It is seen on YouTube.

JosephL on Jul 21, 2013 said:

I look forward to building my 'Lyman Extruder', but I do have a couple of simple questions. 1) Do you have a source for blank 1kg spools and 2) Can the extruder handle PLA pellets and, if so, what should be the temp setting for the extruder

hlyman on Jul 22, 2013 said:

I use the used spools I saved from filament purchased over the last several years.

PLA and other plastics can be extruded. I have only extruded ABS so far so I haven't determined the temp for PLA. I would start at about 170 C. My V3 extruder is now extruding at 190 C with ABS.

TheCatcher on Jul 11, 2013 said:

I must have missed it in the plans... Could someone tell me what size hole to drill to get 3mm filament. I'm getting 1.75mm (1.78mm) with a 1/16th inch hole.

hlyman on Jul 11, 2013 said:

I'd start with a #40 drill .093" diameter and work up

zachjowi on May 28, 2013 said:

What size should the 30 tooth gear be printed at? when I open it is very small and the Makerbot software doesn't ask to convert metric. The 10 tooth opens okay.

hlyman on May 28, 2013 said:

Scale it if you can x 25.4.
Or print in inches

jog on May 23, 2013 said:

Mr Lyman, thanks for providing your ideas for public.

Question: inside the tube, is the melted plastic be in contact with the drill bit?


jog on May 26, 2013 said:

ok, but if "the melted plastic is in contact with the auger" then:

--- there will be a great heat transfer drill bit upwards (from tip to shaft of the drill bit) and, in consequence,

--- more and more plastic, drill bit upwards, will glue/stick on it. After cooling and then heating again, it doesn't happen that this plastic glued will rotate (inside the pipe) together with the drill bit and will not be more transported downwards? Hence, will congest the pipe?!
(Please, don't answer just "no, it will not" ;=)


alisonsp on May 11, 2013 said:

Anyone knows what's the best viscosity of abs filament?? Lower or higher?

TMosl on May 6, 2013 said:

how is work going with the third version ?

hlyman on May 12, 2013 said:

Version 3 is coming along fine. I hope to finish it in the next few weeks. It may take longer to publish it as it is far more complicated than version 2.

As a preview:

1. Direct drive gear motors (2)
2. Water cooling system
3. Re-sizing die
4. Puller rollers
5. Spool winding
6. Motor encoding to sync motors
7. Sabertooth motor controller
8. Spendy
9. 39" long

The mechanical parts are done and wiring is now in progress.
Hope it works

adamb135 on May 2, 2013 said:

Now selling my version of the filament extruded check out my eBay page:

Adam b.
[email protected]

mohannad on May 2, 2013 said:

Hello, congratulations for winning, am building your
extruder, and I was wondering what role does the aluminum bars that are laid
under the heating element play? Are they necessary? Can they be replaced with
something else?

Thanks in advance.

hlyman on May 2, 2013 said:

The aluminum spacers were used only for 1-1/2" heat band. I am now making Version III and using a 1" heat band without spacers. Version III will have water cooling and spool winding.

scorbi on Apr 24, 2013 said:

May I have a few questions? From your experience, what is the general reason for air bubble? When you set the temperature to 212 Celsius degree, did the filament run out of the nozzle by its own? And the last one, when I first extruded the filament, the motor run smoothly and I had about 1m good condition filament, but then the motor get stucked, the vicous filament run out with air bubble, what do you think might be the reason?
Thank you.

hlyman on Apr 24, 2013 said:

1. Maybe your pellets are different than mine were.
2. Motor stopping could be, a) to fast, b) not hot enough.
3. Have no idea about the bubbles, as I haven't had that problem.

Tony3D on Apr 14, 2013 said:

Congratulations for your win. A very well designed machine. The budget constraints must have made this challenging. I wish that I had a workshop handy to try and make one myself.
Was wondering how frequently the diameter of filament would vary over eg say one meter while you are extruding? Also approximately how fast does the wiper motor rotate?
If it is very stable then it would be not worth this extra effort. Exchanging the voltage regulator for a motor speed controller kit - eg a pulse width modulated one. Shine a light at a point near the extrusion nozzle. Then use a photoresistor on the other side as an input to fine tune the speed controller to push slightly more material if it thins etc. This tweak might be far too simplistic but is less complex than a computer control chip but these DIY kits seem to be around the $20 mark.

hlyman on Apr 14, 2013 said:

Tony3D, thanks for the congrats.
Your idea sounds interesting, but the filament as it comes out of the nozzle is soft and it stretches so the control has to be after it exits. I am working now on the 3rd version with a gear motor plus a water bath and a re-rounding die to control the diameter.

hlyman on Mar 4, 2013 said:

I am excited to let all know that I did win the DFC contest. See link below.


PeteD on Mar 4, 2013 said:

Congratulations! Is anyone selling kits of your extruder yet? I'd very much like to buy one.

bfish85 on Feb 17, 2013 said:

About 3/4th of the way done with the build! Question regarding the solid brass nozzle ...on the drawing P09, it looks as if the hole (red dashed lines) is slightly offset from center axis -- is this the case or just how it was drawn? If so is there a dimension for how far off center?

hlyman on Feb 18, 2013 said:

Center is where it was suppose to be drawn, but if it is off it won't matter.

ianjohnson on Feb 14, 2013 said:

Just a note on the iron nipple- If you order that part from McMaster and it comes from the Los Angeles warehouse it will have a bead inside that is thick enough to keep the auger from fitting. The ones from Atlanta have the seam ground down. I don't know about the other locations.

hridge10 on Feb 10, 2013 said:

Can you provide all the specs for the heater band? voltage, amps, exact size ID OD
to use

hlyman on Feb 10, 2013 said:
hlyman on Dec 7, 2012 said:

Possible sources for purchasing a Filamnet  Extruder check with:
zack at inventables dot com
moe at alephobjects dot com

donclark on Dec 7, 2012 said:

Is anyone selling/shipping something like this yet? Im sure there would be many people (like myself) that would buy one.

igor-x on Nov 29, 2012 said:

Hi! tell me pls the algoritm of motor speed control? may be you just change voltage supply on it?

and thanks for good job!

hlyman on Nov 29, 2012 said:

Speed is controlled by voltage regulator, see wiring diagram.

Sabio3D on Nov 29, 2012 said:

Will this work for PLA too? any other plastic?

hlyman on Nov 29, 2012 said:

 I haven't yet used PLA but it should work as well with different temp and speed.

ESN on Nov 16, 2012 said:

HI Fantastic machine but that "kawasaki auger".. Please explain what it is and where to find it( at first i thougt it was a gear shifter from a motorbike then i found kawasaki soil augers via google and then i suggest it was a wood drill bit ) mayby you get the question before but din't at a quick look find it in the PDF..

elmoret on Nov 17, 2012 said:

it's a auger drill bit. search for it on ebay.

bbriggstkd on Nov 9, 2012 said:

Here's a link to the shredder I'm talking about.

bbriggstkd on Nov 9, 2012 said:

How small do the pellets need to be?  I was looking at using the mini shredder to chop up some failed prints and use them to recycle into filiment.  Would that work with your hopper/auger sizes?

hlyman on Nov 9, 2012 said:

 The pellets I use are fine ABS, about 3.2mm long and 3mm oval dia.

mkc2 on Nov 4, 2012 said:

Have Taken on this build and just got one question!
Does the auger bit go all the way up to the end nozzle or stop before the heater band.

hlyman on Nov 4, 2012 said:

 The auger bit stops at the beginning of the heat band.

I have just finished rebuilding my extruder and it is now testing. It uses 1/2" flanges and threaded nipples to eliminate welding.  The hopper base nipple is made with aluminum threaded pipe for easy machining. One other thing I changed was having the auger bit collar up against the shoulder so there is no change of it slipping.
Picture will follow in a day or two

TheLastKnight247 on Oct 24, 2012 said:

Could water be used to cool the filament? I could see a cheap water fountain at the end.

bottleworks on Oct 27, 2012 said:

Some plastic extruders are cooled by water.  You can find a drinking straw extruder example on YouTube.  However, you don't want to cool plastic for a 3d printer in water.  The plastic absorbs water overtime and causes problems with extruding.  So, the goal through the whole life of the filament is to AVOID water and moisture.

hlyman on Oct 26, 2012 said:

 You are welcome to try anything you wish.

bottleworks on Oct 19, 2012 said:

Just posted my derivative...

hlyman on Oct 20, 2012 said:

Very nice, thanks for posting your derivative.  Many enhancements and changes can be made as one choices.
When Inventables returns my machine I plan to add your fan cooling enclosure and Ironmans gears.
Remember, I had to keep the material costs below $250 for the DFC competition.
Another change I plan on trying is to use 1/2" black pipe flanges which will eliminate the welding.

Le-Seaw on Oct 14, 2012 said:

why the components are (. stl) all too small?

hlyman on Oct 14, 2012 said:

If the stl files are small that is because they are Imperial Dimensions.  When slicing the stl files scale them by 25.4 if you're using metric dimensions. 

Ruwaa on Oct 8, 2012 said:

You may want to increase the thermal mass of the hot end such that you can run faster. This would also require more heating elements.

hlyman on Oct 9, 2012 said:

 You may be right, however this would increase the cost factor and I was trying to stay within the $250 mark for the competition.

Thanks for this comment as others may want to do what you suggest.

f4ichuck on Oct 3, 2012 said:

Nice job.

latigerlilly on Oct 3, 2012 said:

any chance you're gonna start making these and selling 'em? I'd certainly like to buy one. I have a bucket of failed prints ready for either your or the Filabot recycler when it becomes commercially available. You're a genius! The planet thanks you for coming up with recycling tech :0)

hlyman on Oct 3, 2012 said:

Not me, Jebba is:

Lulzbot.com  (Jeff Moe).

Thanks for your kind words.  I am not the first.  See the references on the front page of the manual.  I just made it simple and lower cost and it works.

chriscook on Oct 2, 2012 said:

Hey, thanks for answering all of these questions. It's a real benefit to the project to not just have your docs posted and to then walk away.

bottleworks on Oct 2, 2012 said:

Question on the 1/2" insulator section.  It would appear that you don't have continuous pipe in that section...  Am I reading that correctly?  No small pipe nipple in the insulator section?

hlyman on Oct 2, 2012 said:


Your are right, there is no pipe in the 1/2" insulation section, (part #16}. No metal to metal contact between the nozzle section and the chamber section other than the auger. This keeps the pellet chamber from getting hot. Also that is why I used a phenolic washer (part #51} under the bolt heads to isolate the bolts as much as possible.

The last 6 hour run test had the PID temperature set at 212 degrees C and the chamber temperature measured about 30 degree C.

Further, the hopper (part #26D) is glued to the chamber section with epoxy glue.

timmmmyboy on Sep 27, 2012 said:

It would be amazing if something like this could be integrated directly into a printer so no spooling was involved. You'd have to sync the two hotends and the gears driving both but I'm imagining a future where I can just pour a cup of raw filament into the top of a printer and then start printing with it. If the print fails I regrind it and pour it back in. No waste, color mixing possibilties, low footprint, no complicated spool holders and winding methods. This could be so great!

3DTOPO on Oct 3, 2012 said:

 That is actually the goal of the Makibot. Looks like they are making good progress too: http://makibox.com/

crispy on Sep 26, 2012 said:

Would love to see some demonstration of your ability to control the diameter to the level of precision that 3D printers require.  Something like a process capability study (Cp/Cpk parameters).

hlyman on Sep 26, 2012 said:

I don't know how to reply to (Cp/Cpk parameters).
All I know is that the diameter is controlled by three variables,
Nozzle diameter, Motor speed and Nozzle temperature. The precision I was able to get was within +/- 0.05mm.

hlyman on Sep 26, 2012 said:

I just discovered that Page 3 BOM was not sorted correctly in the latest upload of the Manual. Therefore, I have added a pdf file of Page 3 with it corrected.

hlyman on Sep 26, 2012 said:

Part #51 is a small phenolic washer I made as a heat bearer from the bolt part #13 to the hopper chamber part #14.  Thus, the hopper chamber part #14 stays cool enough to touch and the pellets don't get warm and clog up in the hopper.

bottleworks on Sep 26, 2012 said:

Is part #51 for expansion and contraction?

idolcrasher on Sep 26, 2012 said:

Do you think this design would work for printed parts that you ground up into dust?

hlyman on Sep 26, 2012 said:

I would think so as I have plenty if rejects.
If you have a grinder that can make the dust let me know.
I am now designing a grinder myself.

hlyman on Sep 25, 2012 said:

Here is where I got my (fine) pellets:


on eBay - $3.75 a pound.

boulderbuff64 on Sep 24, 2012 said:

This is fantastic! Are you planning on marketing this product?

hlyman on Sep 25, 2012 said:

Not me.

Read the comments and you’ll see who is going to market it. "jebba"

bvac on Sep 24, 2012 said:

Great machine here. What kind of feedstock have you tried extruding? I mean, can you cut up and recycle ABS products or is this for virgin ABS pellets or pastilles only?

hlyman on Sep 24, 2012 said:

I have only used fine ABS pellets as on now.  It should extrude different plastics.  I am now designing a grinder to reclaim other plastics and rejects from my 3D Printer.

hendorog on Sep 24, 2012 said:

Comment removed due to moment of stupidity

hlyman on Sep 24, 2012 said:

I believe it is obvious why I built this machine. To extrude filament for my 3D printer and save a lot of money.  Also it is entered is The Desktop Factory Competition. I used chain and sprockets over gears as it was easier to build. I did print some gears to use but time was a factor for the Competition.
Further the chain and sprockets are less critical in alignment of the motor to the extruder assembly.  The wiper motor has a very short shaft and the sprocket attachment over a gear attachment was less complicated. 

akka69 on Sep 24, 2012 said:

I'm wondering if you can extrude threaded filaments.
Could be useful for a lighter printer  injection head, something like a rotating bolt pulling the filament

hlyman on Sep 24, 2012 said:

You will have to explain what you mean in more detail for me to understand what you are driving at.

idolcrasher on Sep 24, 2012 said:

Wow, very cool :)

Perhaps an overly complex RepRap could be made with a machine like this built directly into it, and you simply feed the printer trash plastic and it makes useful things ;)

hlyman on Sep 24, 2012 said:

I have read of this idea before, however, I have enough trouble keeping my 3D print tweaked without adding another problem to it.

hlyman on Sep 23, 2012 said:


The LYMAN FILAMENT  FABRICATION and OPERATIONAL MANUAL BOM has been updated with corrections to Part #'s 18, 33 & 40 and spelling of DESCRIPTION.  These changes are highlighted with a bold border on Page 1.

jebba on Sep 23, 2012 said:

Great work Hugh and thanks for sharing your inventions!  :)

There are also pellets at http://3dprinterstuff.com, but we haven't tried them.

One small typo correction on the BOM. The URL is monsterguts.com
(plural) not singular (part #33). Looks like quite a fun vendor.  :)

There are three Ventura chains at WalMart. I ordered the 112 link one, WalMart part 301125 (part #25).

Bumperspecialties.com sells the BS-15 in sheets as well, but it isn't
readily apparent from their site which links to a huge box of them. A
sheet of them is available here:


We are building a couple of these, then we hope to add them to our
store. Our contract manufacturer suggested doing it with gears instead
of chain for safety, so we may make some changes after we first build
your version. We'll have a better idea when and how much once we have
one working. We are uploading our files and docs here, as we progress
(early & often!):


-Jeff Moe

JDM_ on Jan 2, 2013 said:

Just design a chain guard similar to a children's bike has. That will solve your safety issue.

hlyman on Sep 23, 2012 said:

Thanks Jeff,

I will correct the BOM and re-upload it.

I forgot about the gears. I printed a set from Thingiverse and was going to use them, however, because the assemblies mount to a 1/2" MDF board, alignment would be more difficult
for me and the chain can be a little off. The large sprocket turns less than 1 rpm. I designed the sprocket tooth from "Machinery's Handbook edition 23" and I had to dress the teeth with a dremel. The 112 link chain is what I used, 1/2".

More dangerous than the sprockets is the hot end. After the machine is run and full of plastic the hot end should be hot to change the nozzle.  I slipped and got a nasty burn on the palm of my hand. That is why I put dymo caution labels all over it, High Voltage, Auger, Hot End and Sprockets.

I must have made a dozen different failed nozzles, till I remembered my motto "Engineered Simplicity is today answer to tomorrows maintenance" and just drilled a hole in a brass plug and it worked great.

Thanks for your Bumper link. I think the sheet has 128 bumpers on it. I glued mine on with CA glue.


hlyman on Sep 22, 2012 said:


FYI: Jeff Moe of Aleph Objects, Inc ([email protected]) is making two extruders at this time and I understand that he is planning on adding kits to his website, www.lulzbot.com. No timeline yet.

fantom on Sep 21, 2012 said:

Looking nice :)

How fast does it extrude - IE length per second/minute/whatever?

The hopper doesn't look huge, and thus I was wondering how frequently you might have to top it up?  

Maybe that amount of pellet actually makes a lot of filament and the size is fine?

hlyman on Sep 21, 2012 said:

I extruded 1.75mm filament at about 8” per minute. The speed is variable.
The Hopper holds several hours of filament, however if you go to page 12 of the manual you will see the optional 3” shipping tube extension which will hold more pellets.

fantom on Sep 21, 2012 said:

Of course, reading the specs and note below the first picture which reads "Extruding at 8 inches per minute" might help.

hlyman on Sep 20, 2012 said:

The following links are parts from eBay.  Do your own search you may find a better deal.

Voltage Regulator:

Power Supply:

DC Fan:  (A larger fan may be better)
Brushless DC Cooling Fan 5V or 12V 24V (Search on eBay as link is to long).

Item # 400299149593 (Search on eBay as link is to long).

Auger Bit:

PID:  (price has changed)

Solid State Relay:  (Now can't find, but others available)  try this listing:

bottleworks on Sep 21, 2012 said:

For the voltage regulator, you may find this one better:
It costs half as much and lacks a voltage display.  IMO, I voltage reading seems unneeded.  Once you have it set to your application, you're done.

scotty1024 on Sep 20, 2012 said:

Source for PLA pellets http://osprintingllc.com/

hlyman on Sep 20, 2012 said:

I checked them out and find that their price is double what I paid for ABS pellets and they offer only one color, natural.

laszlo on Sep 20, 2012 said:

My prototype is sitting on my shelf for a year already. Where I stuck is the colorisation of the granules. And I think its a requirement by Desktop Factory Competition. So I never bothered to finish it, also pricewise it costed 3x more then yours.

So hat off to you sir!


hlyman on Sep 22, 2012 said:

If color is required I missed that. However, all it takes is to mix a colored pellet to natural or white and you should have it.

Your designs may be of value to us all.

hlyman on Sep 20, 2012 said:

To all,

The BOM shows a 1/4-20 x 2" bolt part #18. This is what I had on hand, and my BOM had to match the machine in the competition, however a 1/4-20 x 2-1/4" bolt is what should be used.

hlyman on Sep 20, 2012 said:


I might suggest to all wanting to make this devise that as Inventables is validating this device it may be wise to wait before building one to see what errors in my documents they discover in their making one. I hope none as the 40K will sure help an old retired guy. 

As this invention was done in a hurry to meet the Desktop Factory Competition I am sure there are some better ways and ideas to improve this device. Please share these with us all.

However, this machine works.  I can't wait to get it back for my use.

3DTOPO on Sep 20, 2012 said:

I wish you the best of luck! I am a bit concerned that the filament consistency won't meet their contest guidelines; I remember reading that it had to be +/1 0.01mm... I hope I am wrong!

3DTOPO on Sep 20, 2012 said:

I wonder if the filament was re-extruded though a regular hot end with a 1.75mm nozzle would the filament be a more consistent diameter?

hlyman on Sep 20, 2012 said:

 I don't know, but I would believe so.

bottleworks on Sep 19, 2012 said:

I'm sourcing the parts needed to make a version of this...  For the Kawasaki 5/8" drill bit.  I see you cut it down to 13" in total.  Which length drill bit did you cut down?  The 18" version?  I don't know if Kawasaki advertises the entire length or just the "usable length".

hlyman on Sep 20, 2012 said:

The Kawasaki auger bit I use is the 18" and I cut off the drill point so the total length was 13".  Price was $8.00.  

Please kept your questions coming as it will help all who wish to make this devise, and it will make it better.

3DTOPO on Sep 19, 2012 said:

The need to add a "LOVE IT!" button! ;)

Entropy85 on Sep 19, 2012 said:

Can you describe the ability of the machine as far as filament width consistancy, and any issues with air in the extruded product. 

This is great work by the way, I think i may have to start putting one together. 

hlyman on Sep 19, 2012 said:

 The width consistency is good if it is not disturb as it exits the nozzle. That is why the setup lets the filament fall to the floor. I hope the Lyman Filament Spool Winder will solve this.  Three variables also affect the width (diameter): Nozzle hole, Temperature and Speed of the motor.  All can be adjusted.  The nozzle is drilled with a 0.063" #52 drill bit.  My first run was extruding at 1.60mm, so I reamed the hole with the same bit again and then I got 1.70mm+ diameter.

 I have no idea of issues with air in the filament. As my DIY 3D Printer uses 3mm filament, I extruded 3mm and that is what I printed the 10 tooth sprocket with, as shown in the video. No problem. I also printed the "Stretchlet"

Entropy85 on Sep 19, 2012 said:

I found the width consistancy within the PDF. 

kenwshmt on Sep 18, 2012 said:

The scale is off by 10? on the stl's. tiny. 

hlyman on Sep 19, 2012 said:

I don't understand what you mean  "stl's. tiny."

My stl files slice correctly in SLIC3R.


hlyman on Sep 18, 2012 said:

 Thanks kenwshmt,
I will get it corrected shortly

denis5000 on Sep 18, 2012 said:

Will this extruder work with PLA?

hlyman on Sep 19, 2012 said:


hlyman on Sep 18, 2012 said:

I have just finished uploading the Lyman Filament Spool Winder, thing # 30705.

hlyman on Sep 18, 2012 said:

Yes, the filament extruder will extrude PLA and other plastics. The temperature and speed will have to be adjusted for each type of plastic pellets. I have not extruded PLA yet as I have not found a good source for PLA pellets.  If anyone knows of a good source for fine PLA in 10 lb quantity please post it.  The fine ABS pellets I use are about 2.5mm, whereas the course ABS pellets are about 3.5mm. I have tried both and the course pellets did not auger good enough.

hlyman on Sep 18, 2012 said:


You are correct on the voltage equations. I just happened to find a voltage regulator on eBay with LED I liked for $9.99 and they just happened to be 24V in, variable out and the 24V power supply ($23.99) was cheaper than the 12V power supply I had on hand. And, my target was to create a machine for less than $250 and I was running out of time for submission to Desktop Factory Competition. When I get my machine back I am going to measure the amps the motor is pulling and if low enough I will revise the wiring diagram with the 110V direct to the PID and power the voltage regulator with a $5.00 DC adapter, as that is how I am powering my Spool Windup Machine, which is running great. Besides, as I am not smart enough to do the calculations I use trial and error which has worked for my 7 patents.

Folks, thanks for your comments and suggestions.

bottleworks on Sep 18, 2012 said:

Question: Why use a 24V power supply for the fan and motor? It's a 12 volt motor that your dropping the voltage down further before feeding it. The fans are available in all voltages. Was that something you just had on hand, or is there something more that I'm missing?

bottleworks on Sep 18, 2012 said:

Wow! This blows past all others that i've seen online. Great Work!

dreameredeemer on Sep 18, 2012 said:

One would need to extrude around 14 lbs of filament to break even (given cheap pellets and expensive mbot filament). But that doesn't include recycling, which can be significant; my endlessly tuned tom is still rather unreliable and wastes 10% or more. As far as diameter consistency, I don't see this as an issue with the filament so much as an issue with the printers--future generations should continuously sense incoming filament diameter and automatically adjust the extrusion rate accordingly. Regardless, this is awesome! Thanks for sharing.

ElectronicKit on Sep 18, 2012 said:

I like it! Way lower cost, custom coloring, future proof to changes in filament diameter and DIY.

Price wise, I have seen pellets of ABS sold for as low as fifty cents a pound (when you buy several hundred pounds) and about $5/pound in smaller 5 to 50 lbs batches. Either of those prices would be way cheaper then purchasing the 2 pound spools.

Here's another source for ABS pellets (I have no

hlyman on Sep 17, 2012 said:

ABS pellets I used cost $15 for 4 lbs. I have extruded about 6 lbs. Here is where I got them on eBay:


embeddedprogrammer on Sep 17, 2012 said:

Excellent work. Your pdf documentation is impecdable (especially the parts sourcing info and cad renderings). How much cheaper is it to use ABS pellets rather than buying filament online?