Lego bricks are made using virgin plastic, which I assume means all scrap is not recycled and used to make more Lego.
Some parts, like flexible parts and transparent parts are made using more sustainable materials, whether that consists of some recycled material or plant derived plastics.
When trying to find differences between virgin and recycled scap plastic all I get is AI crap product comparison sites and various companies trying to sell their recycling system…
What downsides is there to recycling your own plastic scrap, which you have had full control over the entire time. I would imagine trying to color match with consumer waste plastic is a nightmare, same with moisture (at least that’s an issue when printing). But if you have a bunch of plastic in an homogeneous color and you grind it up to make something of the same color, and you’ve had the scraps in a controlled environment, then what more issues are there?
The plastic will be grounded up and re-used, that’s 100%, but it still requires quite a bit of virgin pellets to be mixed in. Here’s why:
- Used plastic is dirty. Even if it just came off the belt as a brand new part, it already has dust, oil and other residue. Just a little bit, but it’s not as good as a virgin material.
- You cannot grind down parts into perfect pellets, and that will cause feed rate variations.
- Additives inside like dyes degrade when heated. Multiple extrusions will change product appearance.