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This seems like a question that should have a simple answer:
I have a full, sealed roll of black filament with no markings on it whatsoever. Without trying to load it into my printer and play with temperature settings, is there an easy way to tell whether it's PLA or ABS?
Thanks.
set fire to the end (with lighter or match), blow it out and smell the smoke given off. One will smell very plastic, that is ABS.
Pretty much took the words out of my mouth. That's my professional method of identifying plastics as well, at least the ones I use day to day.
I would suggest taking some known filament and trying it first, if you are worried about being able to tell them apart. Polysulfone, ABS, polypropylene, polycarbonate, and polyethylene are some of what I use day to day and they all have very distinct odors when burned.
bend the end bit of filament backwards and forwards. if it turns white at the bend - it's abs.
If it breaks after a few bends and doesn't go white - it's pla.
Quicker and easier than setting fire to it - though not as much fun :-)
Thanks. As a firefighter, I've smelled enough burning plastic to last me for a while, so I tried the bending method instead.
Bent it completely back on itself and it turned white and didn't break. so ABS.
As a side question, the PLA I have doesn't take well to bending. I tried bending some PLA back on itself and it breaks at around a 90 degree bend. Is ABS that much more flexible than PLA, or is my PLA just brittle?
While PLA does tend to be a little more brittle then ABS, good quality PLA shouldn't break that easily. Check out this video where you can see that's it not all that easy to break a couple strands of PLA filamentQuote:
Originally Posted by iras
If a spool is open for a while the end might get a little brittle, so just cut off a foot or two and it should be fine. If it still breaks easily, it's probably low quality filament.
Just put a piece in acetone. If it dissolves it's ABS. If not, PLA.
That would dissolve things other than just ABS.
He asked about PLA vs ABS. If you've got 20 plastics to identify, no, acetone will not give any definite answers. However, if he knows it's one of those two, I think acetone will give the easiest, fastest answer.Quote:
Originally Posted by Ama-fessional Molder
Quote:
Originally Posted by iras
most pla is less tough than abs. I don't call it brittle myself as I've hit pla with hammers, dropped it, used it for flexible parts etc.
But it is less tough than abs, you should be able to bend it past 90 degrees a couple or three times before it breaks.
The biggest exception is for white pla - for some reaosn that seem to go very brittle quite quickly.
If you leave white pla in your machine for a few days - some brands will just snap when you resume printing. Some snap in the feed tube.
Some don't.
There is something aboutt he white colourant that's used in white filament that makes it less tough than other colours and also more sensitive to environmental factors. Don't know whether it uv light, humidity or what. But the filement on the spool is almost never effected, just the bit from the extruder to the spool.
But only abs goes white when bent.