A comparison of plastics 2016-02-21
3DPrinting
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3D printing is a very cool technology allowing anyone at home to manufacture plastic goods in literally any shape. (Although not quite any size… size is limited by your printer.) The kinds of materials you can print with are limited to those that have a relatively low melting point which are mostly plastics and plastics infused with other materials (such as wood powder or metals).

In terms of basic plastics, I’ve now experimented with PLA, ABS, and Nylon. PLA is by far the easiest of the three to print with, with a lower melting temperature and much less warping (so it doesn’t pull off of the print bed while you are printing). But PLA is brittle and most of the things like belt clips that I’ve printed with PLA have broken before too long. 
Sometimes this is up to a year for pieces that don’t hold too much load, but for others it only lasts a few days.
So I decided to do a side by side comparison of all three materials in printing some rings for sizing a new water pump that needs to fit inside of a PVC pipe.
From left to right: nylon, ABS, PLA

I spent a few hours with each of the rings squeezing them and feeling their material properties, and I decided to try to photograph what I found. Do you know how when you bend something (wood, plastic, etc.) you can usually feel how close it is to cracking? This presumably has to do with the malleability of the material as well as its shape. So I squeezed each ring to feel how bendy it was.

With PLA:

At this point, it bent very little but really seemed to be fighting me. I think if I doubled this squeeze, it would have begun to crack.

With ABS, it bent somewhat more. It didn’t fight me the way the PLA did. I think if I had squeezed twice as hard, it wouldn’t have cracked, but it might not have returned to its original shape and would have deformed permanently.

Nylon just felt bendy. It didn’t feel like it was resisting me at all. It felt like a spring.

I may do a more scientific comparison with screws and bend until the breaking point some day, but for now, it was useful to just feel them side-by-side.