We have previously reported about the potential dangers of 3D printing, but new questions have emerged about the safety of 3D print recycling and the viability of recycling old 3D prints.
Anyone who runs a 3D printer has an abundance of failed or incomplete 3D prints. Since most of the 3D printing being done around the country involves some form of extruded plastic filament, several research groups have looked into the viability of recycling old or failed prints back into an extruded plastic for use in future 3D prints.
If these are your own 3D items and you are sure of the quality and makeup of the plastic used to print them, and you have the ability to grind the plastic back down into pellet sized pieces, then you should be able to recycle them into extruded filament without a problem. Most of us do not have the equipment needed to break down the plastic and remold it into the needed filament for new 3D printing, however, which is where the problem comes in.
Companies that do this type of recycling and remolding for consumers have to be able to verify the quality of the plastic they are recycling. Many plastics, including many forms of plastic used in 3D printing, contain various toxins including coloring and hardening agents. While griding the plastic down is no trouble, the creation of the filament requires the plastic to be heated in order to meld the pellets together and form a filament. If the plastic pellets contain dangerous chemicals, then these will be released as toxic fumes during the reclamation process.
There are dangers to consider when getting recycled 3D plastics to use for your own printing. Just like the any company that does plastic reclamation, you should be aware of the origin of the plastic you are using or have it certified as toxic chemical free before using it.
The 3D printing process requires the heading of the plastic filament in order to be printed, where the plastic re-hardens. If you are using a sub-standard recycled 3D filament, you will be exposing yourself to harmful fumes when the plastic is heated.
Using recycled 3D material is a great, but you need to be aware what you are getting. This is one of those cases where it pays to do your homework.