I thought of that, but the issue there comes from thermal dissipation. It would take longer to get the bar to a molten state, and more energy to keep a suitable amount in a extrudable state, also the chamber would have to be fit to the bar to prevent air from being trapped in a pressurized situation, (if you’ve ever melted lead or metal before, that’s dangerous as gas expands when heated).
The pre-processed shredded material would conform to the chamber, require less heat and pressure, and allow air to escape as pressure is applied.
Ideally, a hopper over a heated auger feeding into an extruder, cooler and mechanical winder, similar to an IMM machine would be doable. However, that’s expensive and requires alot of power or a chemical heat source for the extruder. But even industrial IMMs use pelletized materials.
Hmm just thinking out loud. If you had chunks and extruded it to say 4 mm strand and then just reduced from there. That means a bigger auger larger chunks and perhaps more homogenous colors.
Then you’ve increased the size of the auger, the hopper and the heater, and added another step in the process between extruding and winding, now your extruding, sizing and winding.
If we shredded, the current order of operation would be (assuming it’s all the same material say pla for the example)
sort the material into colours and weigh
wash the materials using mesh containers in a dishwasher and dry using a dehydrator.
feed the material through the shredder, and sort material after by chip size lots
since plastic degrades with each melt, some virgin material would need to be added to counteract (some experimentation would be needed here over time I’m thinking around 10-15% total weight, just to maintain quality)
load the extruder hopper with a lot. The material would pass through extruder, into an open air cooling stage, and onto a mechanical winder, which would automatically weigh the roll and stop the machine at the appropriate weight.
roll would be vac packaged with desiccant
The machines would be cleaned and prepared for the next batch.
Given the time taken to complete each roll, one person would be able to maintain several machines simultaneously.
It would be ideal, but I think there’s going to be some kind of pre-processing no matter what.
I think I would try to keep all the equipment roughly the same floor space as a table saw
I see the conversation around this all the time and it always ends up the same. You run into physics and economics. This is why it’s much cheaper to make your products out of new virgin material from the oil companies, and why most of the collected recycling is going into landfills. If you want to do this expect to have more cost for your materials than if you bought new, but do it because you think it is the right thing to do and don’t mind the cost. The fatal flaw with recycling is if it’s successful there won’t be enough used material around to sustain it and if it isn’t the net cost of the recycled material will be higher than new material.
@Glenn I wish you were incorrect. I have spent a lot of time trying to imagine a machine that would process failed prints and scrap and produce reasonable filament. It is possible but no matter the discussion it requires lots of time space and effort. The worst is a great deal of expertise .
My dream of a box that hangs on the wall you toss scrap and chunks into and when there is enough it automatically extrudes a kg of filament is very far away still.
It’s true. It has to be done because you care. Or as a group effort. My biggest gripe when it comes to 3d printing is the plastic nature of it. I view that tech has a place in sustainable off the grid life, if only the plastic issue could be solved. I believe pla comes from plants btw.
I don’t hate plastic (ok… maybe a little bit) But. If I can make something that lasts years instead of months or days like most plastic is used for then plastic would never be a problem. I’d rather get my bottle of coca-cola in a glass bottle and drink it in a plastic cup than get it in a plastic bottle and drink it in a glass cup.
I think plastic is an elegant material, it is easily shaped can be formulated for a million different uses. We as a society need to rethink how we use it.
I don’t want to make filament. I also cannot get over the plastic filament on a plastic spool vacuum sealed in plastic in a cardboard box wrapped in plastic protected by plastic bubble wrap in another cardboard box.
The reason to exist is my children. My family and I are trying to slowly convert to a subsistence life style. That being said we don’t want to be devoid of tech either, I want to grow food using various techniques throughout the year, solar energy, etc.
3d printing has a role in that, but the more I can lessen the impact the better.
If I remember, I think the Toronto Tool Library and Makerspace collects filament scrap to be recycled. I’ll have to check on that. But that’s all I have heard about.
Just from a quick google search I’ve found this which basically is a service where you buy a box to put your scrap in and then you send it off when it’s full to be recycled. Unfortunately it’s only in the US.
Get to know or inquire at injection molding places. Usually contract places rather than something like Solo Cup. After a job they have tons in gaylords of virgin material thats left over and usually just scrapped.
Don’t they sometimes use plastic shreds for abrasive blasting (aka sand blasting) when they need a little less abrasion then sand? Would 3d printing scraps work for something like that? Then it probably wouldn’t matter if it was a mix of materials.
there was a big movement a couple of years ago with precious plastic. I have started one of the plastic shredder, was considering trying something on my own but a few too many projects going on right now. Something gotta give.
This. Between 3d printing, learning 3d design, coding, and arduino, my children, 10 hr shifts, and shooting trap, it’s far to find time for anything. At. All.
