According to [Alex] It’s easy to make your own rolls of 3D printing filament, although existing off-the-shelf solutions don’t work very well. His explanation for this is economy. He built a filament extruder with an induction motor and high torque gearbox that were sourced locally. He argues that moving heavy equipment would make a similar extruder commercially unattractive. He put about $ 600 into the device, but estimates a company would need to charge at least $ 1,500 or more for the same thing. But that may seem steep [Alex] indicates that a 1kg spool of filament actually only contains about 750 grams of filament and plastic pellets cost $ 2 to $ 3 per kilogram.
There are of course other costs as well, such as the electricity needed to heat and move the plastic. Still, the system appears to use around $ 1 of electricity per 10 kg of filament. You can see the process in the video below.
If you think about it, the mechanism isn’t all that different from a 3D printer. You heat plastic, push it through a nozzle and it cools down. The big differences are that you don’t have to move and have to manage the pellets with a screw feed. It turns out that the screw and associated components make up a large portion of the cost of the machine.
The other key component is a 1 hp engine. A typical engine runs at 1800 RPM, so you’ll also need a gearbox to slow it down. You also need drive electronics, heating and temperature control. If you pay for everything in retail, you will struggle to hit the $ 600 price point. However, the engines and some of them can be found used or salvaged. You can find many details in the second post. The details of the part of the machine that winds the new filament can be found in another post.
If you don’t want to spend that much, you can also make a smaller version that produces around 2kg per hour as opposed to the 5kg per hour that the large machine makes. The little sister uses an eBike motor and the whole thing should come for well under $ 500. There are several other posts linked to the original ones, including advice on the water bath required, how to measure filament thickness, and even how to sell filament for a profit.
We saw a lot of footage of filament making. They even claim to cost around $ 100.
