Comment on Better filament than ABS
dual_sport_dork@lemmy.world 2 weeks agoThat’s because everyone starts with PLA, and PLA has the lowest shrink and warp of all commonly available materials… which is why it’s so common and everyone starts with PLA.
Basically anything is going to warp more and compare poorly against PLA, but ASA’s shrinkage after cooling is less than half of ABS, so it compares favorably to ABS in particular. 1.6% vs 0.7% or something similar. PLA’s shrink rate, meanwhile, can be as low as 0.3% for competently manufactured blends. Shrinking while cooling is what causes warp, especially on broad flat objects.
RememberTheApollo_@lemmy.world 2 weeks ago
Yeah, PLA is easy, it just doesn’t have the temp resistance and durability of better filaments. It’ll warp on a hot car seat in the summer.
dual_sport_dork@lemmy.world 2 weeks ago
Yes. And I suspect due to its low temperature resistance (this an intuitive guess; I’m not exactly a materials science engineer) it also exhibits very poor cold creep/permanent deflection characteristics. ABS is actually the best of the bunch there, probably hand in hand with ASA.
However, one thing people are often surprised to learn or discover about boring old PLA is that it actually has among the highest layer adhesion strength of the commonly available materials, I believe second only to polycarbonate, and it’s also the most rigid of the commonly available (non-filled) materials. At least at room temperature, anyway. It turns out that printing the screws for e.g. my Rockhopper or Adélie in anything but PLA amounts to being a fool’s errand.
It’s tempting to think of the litany of plastics available in filament form to consumers as a simple linear and escalating spectrum with “cheap, flimsy, easy to print” and one end and “expensive, strong, difficult to print” at the other. In reality as you know it’s not quite so simple. If anything, the hypothetical graph describing the properties of PLA, PETG, PET, ABS, ASA, Nylon, polycarbonate, etc. would have to be three dimensional.
RememberTheApollo_@lemmy.world 2 weeks ago
All makes sense, of course. If I want a “pretty” non-structural print PLA is always a top choice. Fine, smooth, easily bonded with CA glue. ABS is a lot more finicky, but strong.