Build Your Own 3d Printer Filament Factory (Filament Extruder)




About: Hi! I'm a maker

Too long, didn't read:

Make your own 3D printer filament !
Cheap and high quality at a decent speed of 150-190 IPM ! (4-5 meters per minute)

UPDATE: Now with wiring diagram !

Long read:

3D printers are cool and they finally start to drop in price. Kickstarter campaigns like the one from QB-UP or M3D are popping up and they are finally "affordable". And with affordable I mean affordable like 200 $ and not "affordable" like 2.199$ affordable. However, once you are a proud owner of a 3D printer you will soon realize that your wallet is far from being let alone. No ! You need plastic filament of course to print those super awesome coat hooks and wheel chocks. Since the price for these filaments tend to top the actual material costs, printing before mentioned life savers is kind of expensive and could become a problem to the development of the ever growing 3D printer community

BUT FEAR NO MORE !! Some clever gents came along - Hugh Lyman with his Lyman Extruder may be mentioned here or the guys over at - and saved the day ! YAY. And there was much rejoicing ! They have built plastic extruders everyone can build or buy at a decent price. However if you are a fellow user the first thing that should come to your mind is "I can build this by myself...and cheaper...". Building at lower costs is the nature of DIY after all.

And much more fun than putting together a premade kit, of course.

Special greetings go out to Xabbax and his plain simple but super awesome Low Cost Filament Extruder !

So how much money do I save when making my own filament ?

Good question ! A lot !

Depending on the pellets you get you can make your filament starting at 1$/kg.

How long does it take to produce 1 kg of filament you may ask ??

Using the build I describe here...roughly 1 hour. (for 1,75mm filament using ABS/PC pellets).

So, let's say on a Saturday in your next workshop session you start at 10 AM and batten down the hatches at 5 PM you could make 4-5 kg of filament, saving between 125-150 $ leaving you with lots of filament for hundreds of thousands of eggcups and phone cases and other useless needful things.

Oh yeah what about the build cost ?

Depending on shipping and local prices, I would guess around 130-150$.

Next step: List of Materials

Step 1: Material List

Except for the electronics everything listed here can be bought at your local hardware store.


  • 1x Wiper Motor (Ebay EU - 15€) / 5€ from the junkyard
  • 1x Auger bit(diameter = 16mm ; length = 460mm)
  • 1x PID Temperatur Controller - DC 12V version (Ebay)
  • 1x SSR-25DA Solid State Relay 3-32V DC / 24-380V AC / 25A (Ebay)
  • 1x K-type thermocouple (Ebay - like this one; does not need to be that shop :) just an example)
    -->!!! Sometimes the PID is bundled with an SSR and an K-Type Thermocouple !!!<--

  • 1x Motor Controller 20A (Ebay)
  • 1x Power Supply 12V, 240W+ (Ebay)
  • 1x Heating band (200 Watt 25mmx30mm) (Ebay)
  • 2x Fans (80mm) 12V
  • 1x Fitting 3/4" US Inch UNC --- 1/2" German Inch - 18cm long
  • 1x Water tap extension - 3/4" UNC threads --- 1/2" German Inch - 50mm long, 27mm diameter (one core thread and one exterior thread)
  • 1x End cap 1/2"
  • 1x Faucet-mounted filter - 1/2" diameter
  • 3x Steel angle
  • 1x Axial ball thrust bearing (Ebay) - Fitting exactly onto the auger bit's shaft.
  • 2x 10mm threaded rod
  • 1x Insulation
  • PTFE tape
  • Heat resistant tape
  • 3x Rocker (previously "rocket") switches
  • 1x Wooden board 100cm x 10cm x 2cm
  • Several screws and nuts
  • 2x sockets (1 that fits on the auger bit and 1 that fits on the nuts of the motor shaft)
  • Wires (two colors)


  • Multitool (Dremel-like)
  • Saw
  • Hammer
  • Drill

Step 2: Base Plate

Take the wooden board and cut away two pieces each 15cm in length (~6"). They will serve as a mount for the motor and for the barrel.

Step 3: The Motor Mount

Mount the wiper motor to the motor mount and place it somewhere at the end of the base plate. See the technical drawing for an estimation.

Use the steel angles to attach it to the base plate.

The motor just has a threaded shaft. For the coupling to fit onto the motor I took a hex-nut with 13mm outer diameter and put it on the shaft. When the shaft rotates and the coupling is attached, the nut would untwist. To fix this I drilled a hole in-between the attached nut and the motor shaft and put in a 2mm steel bolt. This prevents the nut from opening. See the last picture above.

Step 4: The Barrel Mount

Drill two holes into the other piece of wood so the flanges can be attached left and right of the board. Drill another 1/2" hole for the auger bit.

Both mounting boards need their center opening to be aligned to each other so the auger / coupling / shaft-axis can rotate freely.

Fasten the flanges with two pieces of the 10mm threaded rod. The rods must be left long enough so they can be screwed to the auger "kickback protection". 10 cm is good enough. They can be cut to size later on.

This will get clear in the next step.

Step 5: Auger Kickback Protection

When the auger bit turns and hauls the pellets a lot of pressure builds up. In the worst case this could damage the worm drive inside the wiper motor. To counter that problem, we need a kickback protection. This is simply done by a sturdy steel angle and an axial ball thrust bearing.These ball bearing withstand alot of force applied to them.

It works like that: The auger pushed back due to its "backward" turning attitude. Because of its taper the auger's shaft pushes against the axial ballthrust bearing which itself pushes against the steel angle. The coupling between the auger and the motor should always have a little clearance. So that no force is applied to the motors shaft.

Now place the steel angle with the inserted rods at a distance to the barrel mount so that the auger's shaft sticks out for about 3-4cm (~1.5"-2").

The pictures should explain it as well. Moreover I have made a short video that should illustrate it as well. The dimensions of the parts might differ from the ones you have access to. So exact measurement might not help you very much, but the pictures should give you an idea how it should be put together.

Step 6: The Barrel and Auger Bit


Smooth out the ends and the seams of the pipe so the auger bit can rotate freely.

Before cutting an opening into the pipe screw it tight onto the flange and mark the upper area and remove the barrel again.

Take your multitool and cut out the marked area at the end of the pipe where the pellets should fall in. Wind some PTFE tape around that end of the pipe. This should prevent the pipe from turning with the augers movement. Remember the motor is very powerful and if there is some friction between the auger and the pellets, the pipe easily turns another 4-5 mm even if it was fastened with a monkey wrench.

The threads on the flange and fittings are not made for perfect 90° angles. So the fitting/barrel might stand in an oblique angle. To fix this take some washers and place them under the flang where necessary.

Take a square piece of wood and drill a hole lengthways for the pipe to run through. Now drill another hole orthogonal to the "pipe channel" so that a bottle can fit tightly. Now just cut the block in half for easy dis/-assembly.


The auger might be too long so you need to cut off its tip with an angle grinder.

The auger bit should reach up to the heater. See the pictures above.

Step 7: The Auger-motor Coupling

Take a 5cm (2 inch) piece of a square steel that fits into the ends of the sockets (about 12mm edge length).
Put the coupling on the auger bit and attach the motor to the motor mount.

The coupling should now fit nicely in-between.

Alternatively you could use a spark plug socket instead of the two sockets. But therefore the distance between the motor-mount and the auger/barrel-mount needs adjustment.

I went with the above mentioned method because I did not have spark plug socket at hand but I will try this with the next build.

Step 8: The Nozzle

Nozzle diameter:
Depending on the material you process the diameter of the hole in the nozzle will vary and finding the right dimension is a process of trial and error. For ABS/PC blend pellets with a melting point between 240-280°C a 1.5mm hole perfomed well from my experience.

Breaker plate:

Take the faucet-mounted filter and cut it into a 1/2" diameter if needed. This will act as a breaker plate. What this breaker plates does is mix the molten plastic and retains dirty (which should not be there of course) and eventually small bubbles that could occur in the melting process. This helps smoothing the plastic pushing through the nozzle.

Be sure there are no chippings or strands ! You don't want to ruin your printers nozzle !

Take a washer, place it inside the end cap and put the DIY breaker plate on top.

Step 9: Band Heater and Temperatur Probe (K-type Thermocouple)

Drill a 2mm hole near the front of the water tap extender for the thermocouple to fit in.

Strip the thermocouple wire to length. It should just be as long as needed.

Push the band heater on the tap extender. It should sit around the end of the extender.

Next take some PTFE tape and wind it around the thread of the tap extender. This prevents the molten plastic from squeezing through the thread.

Fix the thermocouple with some heat resistant tape.

Then put on the nozzle from the previous step.

Next, take a 10cm long piece of aluminium tubing with a diameter of around 1cm and place it in front of the nozzle using some rigid wire. This gives the filament a nice curl when cooling.
Thanks Xabbax for the idea.

Now wrap the insulation around the heater so that the nozzle is covered as well.

Step 10: Cooling

The front of the nozzle and the motor needs some cooling.

The filament is still very hot and soft when it exits the nozzle. To prevent it from stretching too much from the affecting g-forces when falling down, cooling is very important. The more you cool the better you can control the diameter of the filament later on.

Although the motor builds up some heat and the fan helps to keep it cool.

Step 11: Electronics

Now that most of the mechanical parts are set and done it is time for installing the electronics.
But before, take a piece of wood for the front enclosure and arrange the 3 rocket switches, the PID controller and the motor controller's potentiometer and fix them with some hot glue.

Main power
Connect the power cord via a rocker/t switch to the power supply (Ports L, N and Ground).

PID temperature controller
Connect the PID temperature controller via rocker switches to the power supply.

Solid State Relay & Band heater
Connect the 12V ports of Solid State Relay to the PID (Port 6 and 8)
Connect port 1 of the SSR to the 220V (EU) /120V (US) port (Port L) of the power supply.
Connect port 2 of the SSR to one of the band heater ports.
The other free port of the band heater is connected to the N port of the power supply.

What does the SSR do actually ??
The band heater is a 220V part but the PID only runs on 12V. Therefore the SSR connects the 12V PID with the 220V heater. The PID powers the SSR on and off if needed. When it is on then 220V are connected to the band heater and it gets warm. If the relay is off, the band heaters isn't connected to 220V and ergo is powered down. The idea is to control a high power device (Heater) with a low power device (PID).

Motor controller

Connect the motor controller via a rocker switch to the power supply. Then connect the motor to the motor controller. Use the pinout for the 2nd speed setting of the motor. The pinouts differ from model to model and you first have to find out which pins are for which speed setting.
The two fans are connected to the same ports as the motor is to the motor controller.

Wiring diagram
I am not sure if I am allowed to post the wiring diagrams for license reasons so I will link to the respective websites.

1) Filastruder wiring diagram

2) Filabot Wee wiring diagram (scroll down)

3) Here is a link to the Sestos PID I used.

Step 12: Extrusion Settings and Setting Up the PID

Different materials need different extrusion settings.

For pure ABS a temperatur of 190°C is about right.

PLA requires less heat and ABS/PC blend needs higher temperatures like 260-270°C.

The Sestos PID is able to autotune to the desired temperature.

PID controller setup:

To enable the autotune function press "SET" for 3 seconds.
You will now see "HIAL" on the display. Now use the DOWN button until you see "Ctrl" and adjust it to "2". This is the number for the autotune function. Press "SET" again until you see the temperature readout again. Just after all the EP1-8 options. Set the desired temperature using the up and down buttons and wait until the display stops flashing (~10-15 minutes).

Activate the motor and let the extruding begin. You have to play around with the speed of the motor.
From my experience setting the potentiometer to half speed @ 270°C for ABS/PC performed very well.

Full Spectrum Laser Contest

Third Prize in the
Full Spectrum Laser Contest

12 People Made This Project!


  • Paper Contest

    Paper Contest
  • Trash to Treasure

    Trash to Treasure
  • Remix Contest

    Remix Contest

517 Discussions


22 days ago

Although I've posted in my profile as "hobbyist", I have 30+ years experience as a process engineer in extrusion, on machines ranging from 3/4" to 4.5" diameter, with a wide range of different plastics.

This instructable is great as far as covering the drive, mechanical & electrical aspects. However, this, and other similar designs suffer from the same fundamental design flaw: a drill bit is not a feed screw! A true extruder feed screw has, along the length of the barrel, feed, compression and metering sections, with progressively shallower clearance between the root of the screw and barrel. This is the key to stable melting and output.

I've experimented with one of the low-cost kit designs, with the included auger bit as well as other types (hammer drill bits, which look more like a real feed screw) - collected a lot of data (~1000 points) - measuring not the filament diameter, which is affected by cooling, but the weight/unit time exiting the nozzle. My conclusion is that even for an "easy" resin like ABS, output variability of +/-10-15% is expected. This can be accommodated somewhat with the flow setting on 3D printers, but jams are inevitable on the high end (> ~1.9mm on my Prusa).

I'm still thinking about, if not actively working on, a way to make this little machine more functional. The sticking point is the much higher cost of of a CNC-machined feed screw, many times the price of a kit or Ian's DIY approach.

2 replies

Reply 21 days ago

I am totally with you in this regard. But an auger is the closest part I could get when building on a budget. And those home kits just use an auger an sell it with sky high price tags which IMHO is... You get the point. Using a real feed screw would also require to exchange most of the parts of my machine and effectively the outcome would be a totally new machine.
What I wanted to show with this instructable was that it is paradox to buy such a commercial machine because the soul of this hobby is DIY for the sake of DIY. Not to buy ridiculous expensive kits.


Reply 18 days ago

No reason why a real feed screw couldn't be made to fit inside your design, just needs to have same L/D and drive end to match the auger bit. I admit I took the easy way out with the kit, but at only about 2x cost of the pure DIY route. It was certainly an interesting project, and for me became a challenge using my professional knowledge to see what it could do as-is, and then with various hacks. Not to be too discouraging, but those seeing this design and thinking "I'll never have to buy a roll of filament again" (or, especially, "I can chop up my scrap prints and make new filament") need to understand its fundamental limitations.

There's another way, probably cheaper than a CNC-machined feed screw, to make a screw (still from a drill bit) & barrel (still from a standard pipe) that can generate compression that I'm looking into. Requires machine shop work, but simple lathing and wire EDM (not as exotic as you might imagine). Will keep you posted.


20 days ago

Hi, I'm Farshad and I'm student and I want to make this a good idea. If you can explain to me the drill that you used, I do not know anything about it, please tell me the name and Share application standard for it and say how it should be selected, for example, a suitable spiral angle with the drill to keep the material from burning safe.
Thank you for your attention


8 months ago on Step 11

hi i am going to make one of these. I willl however be electrically grounding the barrel section . With a heater powered at mains voltage the metalwork near the heating element must be grounded for safety reasons. Without grounding its possible that due to a electrical fault that the metal parts could become livened up to mains voltage.

So ground the barrel in accordance with your local rules on electrical mains wiring.

1 reply

Reply 4 weeks ago

Hello. Have you finished the extruder? Did you like the results?

Cem Ege

Question 5 weeks ago

What is the diameter and wall thickness (size) of the barrel? Thanks for your attention.


7 weeks ago

I run a CNC machine that produces a huge amount of rice size HDPE chips. This is technically King Starboard if anyone is curious about the exact material.

I am interested in recycling these chips into printer filament. Does anyone have any experiences doing this with HDPE? Tips, suggestions, etc..

Will it work or is there a reason it will fail? Thanks for any advice.


7 weeks ago

Has someone tried out to make vhs cassettes into filament? I have lots of old vhs cassettes lying around, ready to be shredded. I believe they are made out off polystyrol - should behave something like ABS.


Reply 2 months ago

I got my pellets from a local distributor for industrial plastic processing machines. They also sell pellets. Around 0.90 to 2€ per kg. But only in bags of 25kg. Your best chance would be to study your yellow pages for similar companies.

Buying pellets from 3d print shops is not an option as they sell it often for exorbitant high prices where buying ready to use filament is cheaper.


Reply 2 months ago

Okay thanks, I‘ll ask my uncle, he works in this kind of business


Question 2 months ago

Hey, i'm currently building the extruder on my own. The only part that's still missing is the band heater, but I have already tested the motor and so on and now I have the problem that it always gets stuck when I put pellets in the hopper, but I'm not really sure why!? Has anyone else had problems with the hopper before? Thanks in advance!

2 answers

Answer 2 months ago

Hey Philipp. I had the same issue once in a while. I think the bottle neck is the bottle neck. A wider opening could help.
on my build the are many sharp edges in the pipe and I think there the pellets get in between and if the motor is not strong enough this could lead to jamming.

Maybe rounding off the edges and on the pipe and building a larger intake could help.


3 months ago

I'm a student (on a budget) who wants to build and use this in an assignment but I need some more guidance on how to actually build it and on some of the materials. I'm American and I think some of the parts listed here are British, so I'm having a little trouble trying to actually find them. It's harder for me to buy parts that are from foreign sellers like China because I'm on a deadline and they might not get here on time so I need help finding suitable alternatives. I also can't find some of the parts listed like the faucet-mounted filter or the water tap extension. Some of the materials listed are also pretty vague in specific type of part of dimensions like the steel angles, the fittings, end caps etc. I found auger bits that are as close to the one listed in the materials but they're 5/8 inches in diameter and either 18 or 17 inches in length. 17 inch one is cheaper so I want to use that one instead but I don't know how much that would affect the design or how to compensate for the differences.
If any of you could give me a thorough walkthrough of all the materials (and what exactly they're used for) and the building process it would be greatly appreciated. Much thanks.

1 reply
ianmcmillS A D B O Y S

Reply 3 months ago

I am glad you like this build and that you choose it for an assignment. I'm a teacher myself and I'm happy to help you with that. I am from Germany and as you, I had the same issue with different size standards when I built this extruder because most of the parts from different instructions (Lyman extruder) were US. There is also a difference between British and German pipe fittings. 1" British fitting =! 1" German fitting. That is something that triggers my everytime. Metrics and (ancient) Imperial. Same with cooking recipes. Gramm vs. Cups. When I read measurements like 1 3/4" or 0 5/64" (2mm) the hairs on my neck stand up.

Let's start with the obvious. The electronics from China. You cannot get around those electronics from China when it comes to the price. So if you have a deadline, order the PID controller right now instead of tomorrow. Or maybe there are some resellers in the US who stocked up on chinese electronics. This is what we have here in Germany. Resellers that specialized on keeping a stock of those often ordered chinese electronics. They might be slightly more expensive but the delivery is much quicker.

Faucet-mounted filter / water tap: I realized from the comments that these two parts seem to be typical for the German/EU plumbing sector. So I cannot help you with that. Sorry.
Now for the all the other materials/dimensions/length like angle, fitting, auger bit:
When I started this build, I had no material list but just the pictures from some of those pricey Extruder kits. Basically what I did was to source the parts that I thought I would need and of what was available to me.
I started with the auger and a pipe fitting and build the rest around those two parts. Most of the material I got from my local hardware store. I guess that is Lowes or home depot in the US.
Does the auger easily slide into the fitting? Check.
How much space does the auger have? Roughly 1 mm. Check. Should work.
The water tap extension can be anything that could be used to have the heater wrapped around. I just went with that because it was made out of brass and the surface was very smooth (compared to those cast steel pipings). You could source anything that has similar properties or grind and sand a standard pipe fitting to make it smooth.
In general, the whole extruder is sourced-by-availability project.
It is not important if the auger is 17 or 18". At least I cannot tell the difference. We are not doing rocket science here. The same with those angles. Grab what you think will work. Don't rely too much on instructions. Replace parts with what you think could work better. Most of the time it will work better.

Good luck and show some pictures when you'r done. I would like to hear what your lecturer/teacher says about it.


Question 7 months ago

Hope you are doing well. I am a social worker in India and have the passion to work towards making our environment more sustainable. I was volunteering with some of national NGO which are working in waste management. While working with them I found out that the management of plastic waste is a huge problem. This problem becomes very dominant in the regions like Himalayas where every year thousands of tourist are coming and tourism is increasing at the fastest rate. I have seen huge piles of plastic waste in the Himalayan region.In 2015 it is estimated that every day 30,000 PET bottles were getting dumped in landfills every day. In 2018 Tourism rates almost Double and hence the volume of waste is also increased. This waste is affecting local ecology and underground natural water resources. Since past couple of days, I am researching the methods to upcycle the plastic PET.
Now I am planning to open a non-profit organisation to upcycle the plastic and develop the Himalayan region. My objective is to upcycle plastic waste being generated in the Himalayan region into high-value filament used for 3D printing. I am aiming to convert 10,000 Kg of PET plastic into filament using plastic extrusion machines in first run. For piloting the idea I want to set up the project in Leh,Ladakh, India region.
I am struggling in determining the technical specification for the machine. Since the volume of waste is huge I want a machine to handle such a large amount. We also want the machine to be energy efficient and suitable for the weather condition of Leh. So regarding this, I have a few questions which I am listing below.
1. Operating and maintenance cost.
2. Handle capacity.
3. Operating temperature of extruder machine.
4. Machine cost required for the process.
5. Market to sell and selling price of Filament.
6. Process to convert PET bottle into 3d printer filament.

We are looking for help from organisation who are already successfully convert PET from waste PET bottle to 3d printer filament.

Also, temperature of Leh where we are planning to install the machine varies as given below:-

March to April:- 6 degree Celsius in day to -5 degree Celsius in night.
May to August:- 16 degree Celsius in day to 3 degree Celsius in night.
September to November:- 22 degree Celsius in day to 0 degree Celsius in night
December to February:- 2 degree Celsius in day to -20 degree Celsius in night
It would be great if you can help me figuring out the specifications for the machine and clear my doubt. I would be very grateful. looking forward to hear from you.

Your one reply can help us making Himalayas a better place again free from plastic pollution.

Thanks and wishes.

Nagender Pratap Singh
Contact:- +91 8307555556

1 answer

Question 4 months ago

What is the best way to keep filament thickness constant?
Im thinking about making 1.80mm filament, and using some diy device to process it to exactly 1,75mm.. opinions about that?