The longevity of plastic is both a blessing and a curse. On the one hand, it’s extremely durable, inexpensive, and easy to work with, but it also doesn’t biodegrade and lasts indefinitely in the environment when not disposed of properly. While this can mean devastating impacts to various ecosystems, it can also be a benefit if you happen to pick this plastic up and also happen to have a laser cutter around.
After cleaning and sorting plastic that they had found from various places, including scraps from a 3D printing facility, the folks at [dinalab] set about turning waste plastic into something that would be usable once more. After sorting it they shredded it and then melted it into sheets. They found that a sandwich press yielded the best results, as it kept the plastic at a low enough temperature to keep it from burning. Once its off of the press and properly cooled, the flat sheets of plastic can be sent to the laser cutter to be made into whatever useful thing they happen to need.
Not only does this process reuse plastic that would otherwise end up in the landfill (or worse, the ocean), it can also reuse plastic from itself since the scraps can be re-melted back into sheets. Plastic does lose some of its favorable material properties with repeated heat cycles, but we’d have to imagine this is negligible for the types of things that [dinalab] is creating. Of course, you can always skip the heat cycles entirely and turn waste plastic directly into 3D printer filament instead.
Good idea, but too colorful for my taste, how to make it normal?
Simply don’t melt different colors together. Video already mentions sorting plastics by type and by color, so most patterns you see are like that by design.
The process shown doesn’t seem to allow for mixing of the molten plastic, so I doubt you could dye a mixed batch using colored pellets.
Use only one color of source plastic – it looks like a lot of the rainbow/tie-dye patterns on these were intentionally made by placing source plastic of different colors into the press in a matching pattern.
Yeah it’s super easy to make it more regular colors! You can either a) just use one color plastic or B) you can also spray paint a lot of the plastics pretty easily (except HDPE which doesn’t stick to the paint well)
It looks horrible, indeed.
:o)
This works with waste plastic of known type. Usually they are melt compatible – albeit of mixed colors, so when heated they melt at the same temp and all the particles fuse together = ideal to press flat. Plastics from recycling house hold waste would not be suitable. Production like scrap is suitable and most such waste is already recycled back into items or collected to be blended and re-pelletised. Complex here as color and filler are added. so any combinatorial recycling converges towards a muddy brown of mixed pigments. Many fibrous fillers also add problems as they must be stored and added to compatible mixing types. Often companies just dispose of some small streams by combustion for heat/steam.
The other aspect is labor – this might not be economic.
That said, there needs to be a structural cost to force people into recycling as well as an import structural cost added to cover the downstream cost of recycling. To be clear – plastic is charfed a fee by US customs(or any nation customs) that is segregated and paid to the companies that are burdened with the recycling cost at end of product life. This added cost will serve to reduce imports in volume and of type – each type of plastic has a code. Random toys will also get that charge – which will be in the area of $1-2 dollars per pound of finished item/toy etc. We MUST get on top of and control this sea of garbage…
Hi! I’m the one who was doing this at our house, and we primarily use household waste. Clean plastics #2 #4 and #5, works great! :)
Great project. The stuff they make looks good and functional. I’d be interested to see how many families of plastics are usable. Even if a plastic doesn’t melt it could still be used for fill.
Reusing makes sense. Recycling makes sense. But I think biodegradable plastic is a mistake in most cases. Don’t get me wrong. I think plastic in the waste stream is a tragic waste of resources. In the end I don’t think the best solution is at the plastic production side with water or UV degradable formulations.
“Biodegradable” isn’t all it’s cracked up to be. I read about an archaeological dig that was done on a 1950’s era trash dump in Texas a few years ago. At the bottom of the pile they found carrot tops wrapped in a newspaper. The carrot tops were still green and the newspaper was still readable. Carrots-biodegradable. Newspaper-biodegradable. The environment they were stored in wasn’t appropriate for these very degradable materials to degrade. Since biodegradable plastics need sunlight, air and water to degrade, unless waste management techniques change significantly they would take up space in the landfills, too.
The main objection to plastic in the environment is that it doesn’t degrade. Last time I checked, glass, bricks and rocks aren’t terribly degradable. We admire and praise stone and brick things made a thousand, two thousand years ago that haven’t degraded. And we complain when metals degrade–just ask anyone who’s ever owned a 1970’s era car. Building things that last is good, provided they’re useful.
I think the best answer is recycling but not how it’s been done. Managing plastic waste at the consumer level is best if the consumer is able to cooperate but As Andy mentions, a lot of the “recycled” materials end up in the trash. If the consumer route continues to fail, I think someone is going to do the math and realize that pound for pound the average landfill has more usable materials than a mine. A profitable iron mine or copper mine does have the advantage of producing a single product.
On the other hand, if ChemCam can identify material compositions on Mars then there’s probably hope for sorting plastic (and other) materials for a recycling operation. There have also been a number of processes that can separate polymer families chemically. Maybe a combination of spectral identification, separation and chemical processing will make it profitable enough that , bidegradable or not, plastics will be a resource without trashing the environment.
filament producers should be forced to take in old filament, and recycleit to new filament
before that, they should be forced to use spools made of cardboard instead of heavy-duty plastic.
It’s a shame they can’t make larger blanks, I would love to make some patio furniture out of that stuff! Yep, sitting in a plastic Muskoka chair, cold can of beer, couple of barbecued agoutis, that’s the life.
That’s pretty good. I think you’d need to be a little careful about the structure, but making a bigger hotplate shouldn’t be a deal-breaker.
Check out https://preciousplastic.com/ they make what you are looking for.
well PP, PLA, and HDPE are all on the do not cut list because they don’t cut well or make a mess at our local makerspace. but might be worth getting a 40k or something to play with it with. he glosses over #6 plastics. you can work with them with orange oils or lavender oils. i did a guide on it. might try out his sandwich press idea on it to help cure some flat blanks. https://www.instructables.com/Recycling-Styrofoam-EPS-Into-Castable-Styrene-Plas/
That thick lumpy plastic looks ideal for big stuff that just needs to be robust and cheap – like water butts, buckets, plastic lawn furniture, and parts for tools (EG lawnmower bucket) that kind of thing.