Pla recycling/reuse options

Is this a thing? Seeing as how we are using a plastic, we really should be getting the most use out it we can,

I keep a jar full of my cut ends and scraps, with the idea that maybe I can do something with it. Honestly I was thinking of melting it down and molding something with it, using 2 part aluminum molds, (I was thinking of homemade snapcaps, but to each their own)

However I have seen references to a recycling system available for filament (filastruder :face_with_raised_eyebrow:). Does anyone have any other info on this? Or maybe some ideas for what to do with scraps?

Might be able to make cutting boards but most use HPDE for that as it’s considered food safe. It’s a challenger for sure, just like the empty spools. I try to by refillament as much as possible but supply is often short for spoolless PLA.

I’ve often thought of a filastruder but I think you might spend more time baby sitting it then you do using the product!

I agree I wish there was something to do with it all. I have a vision of being able to take scraps to a place and drop it off get a discount and pick up some recycled rolls. I suspect that is a pipe dream as if one person isn’t diligent in separating each type of filament out it will jam the line. I also am trying to think of something to form scrap into but I cannot think of a single thing that will alway be useful. I keep looking at home extruders but it still seems crazy problematic.

I have a large Rubbermaid half full of Skirts, Fails, Supports.

I was watching the CNC kitchen video about re-molding /re-extruding back into spools.
Thought it would be a good idea for print’s that colour didn’t matter.

Alex, that’s True, i can’t guarantee that someone wouldn’t mix up material types. that’s why i’m accountable for only my scrap.

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Sad really. I also have a pair of boxes of scrap. I had also been putting little bits from under the printer in one when I realized I was likely mixing planning and PETG up doing that. I looked at the CNC kitchen video and a second one as well they both had the same issue breaking the parts down fine enough. I thought a big roller mill and then a fine shredder. But who has space for roller mill, grinder of some kind and extruder…

Honestly it seems like the largest hurdle is the separation of the scrap. I wonder if something like a hardness tester would be able to distinguish different plastic types with a reasonable degree of accuracy.

So you can test you material. If it does disolve it is ABS. If it smells sweet when burned it is PLA . If it melts at 240 and does not dissolve it is likely petg

This is an interesting statement. There’s more to cover sure but this gives us a base

I would actually be interested in creating a recycling program for basic 3d print filaments, maybe I’ll have to get to work on a filastruder. Seems like something worthwhile to do

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I have two thoughts on this and I’ll post them separately.
First, if the folds at 3DPC are reading this, I wonder what the largest spool of filament they can get is? If they could get the basic colours (or at least white and black) in a mega-roll format, local customers could bring in empty rolls to be re-filled. Obviously this wouldn’t be economical for customers outside of regular driving range, but they are near the junction of the 403 and QEW so a lot of people would be passing within 10min of them on a daily basis. It might be viable.

My second thought is that one can buy storage bins/drawers at Canadian Tire or at thrift shops. I keep all my filament scraps sorted by colour in separate drawers. Mind you, I only print in PLA so that makes it easier. I’ve done this specifically with an eye toward one day being able to melt it down and re-use it.

With respect to storage of scraps, I’ve been thinking about finding some silicon molds into which the scraps can be put and melted down in to a block in the oven. That would save a lot of space.

I’ve seen some people who have melted their scraps and moulded using more traditional casting techniques. It doesn’t become 3D printed, but I think it’s a low effort reuse project, especially if you’re into repetitive projects like gaming tiles.

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(Might be double post)
So im looking at a extruder and winder online, this might be something I’d be willing to make a go at. The price isn’t terrible if the quality is there.

Heres a guide for ID’ing plastics that might be helpful

https://www.stanmech.com/uploads/2/1/0/9/21099874/plastics_identification_flow_chart.pdf

Thanks!
Right now I only print in pla, so for me it’s not an issue yet, but soon? Who knows

A family member sent me this a few weeks back, & your post sparked my memory to check it out. Incredible, recycling is the way to go :smiley: I wanna start doing this & possibly adding plant material from my garden to make Recycled plastic w/ plant particulate filament

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Oooh I like that article. The plant mix though, I’d be worried about degradation from the vegetable matter. Wood is a little more stable.

That being said. It never occurred to me at the start of this that plastic bottles could be used…
The gears in my head are turning fast enough to melt plastic now.

A shredder is actually not too difficult to procure. And with some gearing a regular table saw motor would provide ample power… Actually… just spit balling but table saw blades running slowly through a fitted trough, would probably do better then thicker duller blades, and would be easier to replace/sharpen. Use 0.60 aluminum for a riveted hopper, and 1/4 plate for a body with a hardened steel shaft. Hmmmmmm…

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@Benchy the way you phrased

I keep seeing the reduction of scrap to particles fine enough to hopper feed as one of the draw backs. It is potentially dangerous and hard to control. I have been thinking of a crusher before a shredder. I wonder if a drum with something a kin to a cheese grater would work as a chipper so to speak?

It would be safer, but would require much more power. Safeties would have to be included like not being able to have the motor running with the hopper open, or the the blade change door open. These are just limit switches, at the bottom have fine mesh screens to control access.

Honestly this is no worse then using a chainsaw, a table saw or a reloading your own ammunition. LOL
Needless to say I’m an insurance nightmare

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That is very true. I power kite, don’t ask how many bones I have broken…

Some of the videos talk about particle size do you thing a series of blades will reduce large chunks to 4-8 mm squares?

No matter the system high torque is going to be needed.

I think it could. Some fine tuning of the blade spacing would be required, and not all of it would be one size. You would wind up with some small bits, as he shows in the video, that’s why you’d want reducing screens. I don’t know how crucial it is for an extruder for all material to be same size however. I’m assuming it’s for an even melt at the nozzle without any clogs, and without having to maintain a large hot section.

As far as torque, with sharper blades the torque would be reduced, requiring a less robust motor, but you would want slower rotation, luckily this is easy.
It’s just a matter of figuring out the ratio

Personally, I think you’re all going about it the wrong way:

Buy some tubular silicon molds, say 2cm x 2cm x 30cm.

Fill them with scraps and melt it in an oven. Keep topping it up as the plastic melts until the mold is full.

When it cools, you’ll have a roughly uniform sized bar of plastic.

Instead of an auger system for fine chips, use a weighted plunger to push the plastic bar into the heating element of the extruder. This should be a lot simpler mechanically and eliminate the need for pre-grinding material.