Aloha,
I got an Elegoo Carbon FDM coreXY printer and a roll of PLA from the same brand. I’ve read that some filament brands are better than others but I figured I’d start easy.
I’ve taken STLs to the library to print, but I’ve not done my own before. What’s all this slicer stuff? What other software and tools do I need? Thanks!
On the one hand, yes, prints do age, on the other hand, the mechanical requirements for filament during printing are much more intense than on a finished part. So usually, unless they have to constantly resist mechanical load, UV or flowing water, printed parts usually last much longer.
The issue with filament is that it’s a rather thin strand of plastic that’s pulled with a lot of force, that’s being bent out of shape (by being unrolled) and then heated to 200+°C.
The kind of bending and pulling that filament has to survive by unrolling it from the spool is rare for finished prints, and melting in a way that it still sticks to a new layer afterward isn’t easy on the material either.
Some filaments (e.g. PETG, TPU/TPE, Nylon) are hygroscopic, so they draw water from the air. In a finished print that’s usually not a problem, but during printing it is, because when the water in the filament hits the hotend it’s instantly (and rather violently) turned into steam, which leaves small air bubbles in the extruded plastic like miniature swiss cheese. That causes stringing, bad layer adhesion and brittle and ugly prints.
You can still print old filament. You can dry hygroscopic filaments to get them better. But old filament will lead to weak and often ugly prints. The other day I printed with 4yo Silk PLA. It did complete the print, but there were multiple areas where the layers didn’t adhere and you could just pull the layers apart with very little force.
Some old filaments (especially PLA) become brittle like spaghetti. You try to unroll them and they just snap. Sometimes it’s only the outer layer, so you crack away a few rounds of spool until you end up on a deeper layer and find filament that still works.
So the 1-2 years isn’t a hard limit but a good guideline. No need to toss old filament that still works. You can still use old and bad filament for test prints or other garbage prints that don’t need quality.
But you should in general plan to consume your filaments within 1-2 years and not overbuy so that you are left with a ton of aging filament.
And to answer the original question: I have printed parts that are 8 years old and are still in good condition.