Jim, I noticed the same things about the article. I included the link as an example of what's out there. If you Google "PLA and 3D printing", you''ll come up with a lot of other sources, some of which have a very different take. Beth's article says "PLA was chosen because of its strength and ability to make very large prints without cracking or warping."
Gosh, Ann – That article is less than encouraging as an endorsement for PLA. It actually says it is best used as the support-structure for the primary material being ABS; that the PLA will degrade away, leaving the host ABS in place. The article is about 2 years old. I'm hoping that if MakerBot has invested their product line on this material as the primary building block, that it has rugged, stable material characteristics. Guess the Jury's still out.
Beth, I notice that the Replicator 2 uses bioplastic PLA, not ABS. This appears to be an emerging trend in additive manufacturing, at least at the higher end. Do you know of any other 3D printers that use bioplastics?
Linear guides are one of the most important components required for the development of automated or computer-controlled equipment. Aluminum profile extrusions, used for these guides in machine design, can enable designed-in functional features.
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