Some 3D Printed Objects Are Toxic to Fish | Hacker News Reader

Some 3D Printed Objects Are Toxic to Fish

forbes.com

22 pointsthealexknapp9 comments

Holy smokes Forbes provides a painful reading experience.

Here's a post about the same study from the American Chemical Society -- http://cen.acs.org/articles/93/web/2015/11/3-D-Printed-Parts...

tl;dr, the study found the stereolithography printing[0] method to be harmful, and less so for fused deposition modeling[1].

Many of the 3d printers you'll find around community-level makerspaces employ fused deposition modeling (those that melt plastic filament, as opposed to those that use liquid plastic).

[0] http://www.livescience.com/38190-stereolithography.html [1] https://en.wikipedia.org/wiki/Fused_deposition_modeling

While reading, it immediately occured to me: perhaps the problem can be mitigated in the stereolithography process by exposing the object to additional light for a fuller cure?

Then, lo and behold, there is a paragraph about this obvious step. Then, at the end of the paragraph: [t]he UC Riverside Office of Technology Commercialization has filed a patent on this technology.

Please tell me this doesn't refer to the painfully obvious idea of more fully curing the finished object by shining additional UV, like is done with tooth fillings and nail polish, not to mention entire pieces of furniture.

Congratulations, UC! You've invented UV curing chambers.

https://www.google.com/search?q=uv+curing+chamber&tbm=isch

Can I get a patent on putting food in the microwave for a few seconds if I realize it wasn't cooked all the way through?

You see without patents like this companies wouldn't invest in this level of R&D and we would all still be throwing shit out of our windows with buckets on the street and using lead plumbing.

As much as I dislike how the patent system can stifle innovation, I'd like to point out that the fact that this step seemed obvious as you were reading the article is not, in itself, evidence that that step is inherently obvious.

When writing academic papers that involve some new insight (in my field, it's computer graphics), a recommended way of writing the paper is such that, by virtue of how you describe the problem and the current shortcomings of the state of the art, the reader should almost be able to guess what your solution is by the time you actually reveal your own insight. If a description of a new method is well-written, then by the end it may feel like an obvious thing to the reader.

So, sentences like:

> Grover, Oskui, and their coworkers think that the reason stereolithography proved more toxic was that the 3D printed parts were leaching leftover building blocks that didn’t fully cure.

might be a description that hides additional background work.

Filing a patent is different from getting a patent granted. Having actual patent might still be unenforceable. For example because it would have been obvious solution to professional on the field prior filing.

Typically minority of patents are actually enforceable.

To clarify the title, the findings are related to liquid resin-based methods vs. the much more common FDM method (usually extruded plastic filament) method.

The latter is usually ABS or PLA plastic, both of which are as theoretically safe as any other plastic in your home. PLA is a bioplastic and is actually compostable.

The resins, on the other hand, are pretty nasty and require gloves to work with. The safety data sheets are pretty serious and even mention that they are dangerous to aquatic life.

For that matter, solid-based 3D printing can even use sugar, and make edible products.

Clickbait headline: "3D printed items contribute to obesity!". :)

There was no difference between the control experiment and fish exposed to parts made with FDM.

Read the article to see how FDM could become toxic/harmful, turns out it didn't.

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