So the first thing we have to think about is what to do with all of your old failed prints of course recycling plastics will be the answer.
Over time you get many failed prints and if you are like me keeps all of the failures in the hope that you can use them for something useful.Plastics need to be disposed of in a proper manner or be recycled.A lot of plastics end up in landfill or go to special recycling plants.Once at a plant they are sorted into all of the different types and dealt with accordingly.
For a DIY person you can deal with some of this yourself by maybe making a shredder and a filament maker.
So what is a shredder , well as it suggests it is a machine to take various plastic in which you can shred/crush and turn into little pellets which in turn can be heated up and turned into filament.
If you do not have any plastic to shred , the best way to obtain stuff is to look around your own home because there are many different things that can be recycled eg Plastic bottle/bags/toys – most will have recycle marks and codes to tell you what type of plastic you have.
And if you start to get serious with making filament you can purchase pellets from a lot of companies and recyclers.
Identifies the type of plastic resin used to make the item by providing a ‘Resin Identification Code’. It is represented with a ‘chasing arrows’ symbol surrounding a a number between 1 and 7 that defines the resin used.
Shredding Machines – recycling plastics
There are a few commercially available machines with correspondingly high prices , after all recycling is big business.
Followed by some open source machines – recycling plastics
So looking at the open source machines they seem to comprise of a hopper so you can feed in the scraps of plastic which in turn drop on to some steel rollers that turn the plastic and crush it into small pieces and fall in to a hopper,
Some of them even include an auger bit which drives the crushed plastic along a tube which in turn heats the plastic and pumps the melted plastic through a die (say 1.75mm in diameter) and cooled as it comes out spooled on to a reel which is then ready to be used as filament for your 3D printer.
So how easy is it to make a shredder and extruder – recycling plastics
There are quite a few open source projects on Instructables and Thingiverse , a quick search will give a number to look at , read the instructables and see if if you feel confortable building one yourself.If you dont want to build it yourself but still dont want to pay the very high commercial prices leave a message in the comments and we can discuss building the machine of your choice.The Lyman one looks very good to me , also the best set up I have seen is in the picture below from Precious Plastics
So if this gets you in the mood and you make/commission one to be built then you are also helping to save the planet.
On a more positive financial note if you put in say an 8 hour shift making filament you could end up with 6/8 1 kg reels of filament – value of course depends on how much you would pay for your reels.