~~~~Original Email~~~~~~~
Hi,
We are a student group from the USC's Digital Manufacturing class. We are currently working on a semester-long research project regarding the current and future recycling processes, prospects, and expectations of Fabber materials. Recycling is a major part of our society today, and in order for Fabbers to reach a prominent status in the future, we believe most, if not all, of fabber materials should be recyclable. We are doing extensive research on current and future recycling processes, and we need as much information on current and future fabber materials as possible in order to perform any type of analysis. Yet, there are very few resources out there on fabber materials. Referred by our professor, Marshal Burns, we are sincerely requesting some assistance from
your expertise.
Thank you for taking the time to read this email.
We strongly appreciate all of your help and kindness.
Sincerely,
Kevin Zhang, Brain Hsiao, Danny Chen
Industrial System Engineering Undergraduates
Viterbi School of Engineering
University of Southern California
~~~~~Response~~~~~~~~~
Gentlemen:
Thanks for your letter. I've made a few comments within the body of your text:
***EG: Indeed you are correct in your assumption that this will become a bigger issue as time goes on, and it's very useful for society to think about this now - before explosive growth in the field buries us in waste from additive processes. Fortunately, I believe there's sufficient time to do this, and probably a lot of desire within the industry to make sure ahead of time they're not caught in this potentially costly trap.
Marshall is, in fact, one of the few people to have done an extensive tabulation of RP materials in the past. The only people I know of who've carried this on are CADCAM Publishing which has been subsumed in the last year or so into:
Cyon Research Corporation
8220 Stone Trail Dr.
Bethesda MD 20817-4556
301.365.9085
301.365.4586 FX
info@cyonresearch.com
Dr. Joel Orr, Chief Visionary
I don't know whether they've carried this on or not after the merger/purchase. I doubt it because there's little economic incentive to do so.
***EG: You've attacked a big problem and you might want to limit your work to either defining the future issues, or seeing what's what in detail with a specific class of materials. I'd be very interested in receiving your final report.
Please give my regards to Marshall.
I hope this helps and I send best regards.
Ed Grenda
Castle Island Co.
19 Pondview Road
Arlington, MA 02474 USA
781-646-6280 (voice or fax)
EdGrenda@aol.com (email)
The Worldwide Guide to Rapid Prototyping
http://home.att.net/~castleisland/
Specific Questions and Answers
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Q1:
If possible would you send us any available "information or opinions" regarding the current and possible future fabber materials. What are the available fabber materials today?
A1:
***EG: I would suggest you look at our site under the RP brief Tutorial, FAQs and bibliography sections to get some idea of what today's materials are like for various processes. The future will look much like the present, but there will be a much greater variety plastics and photopolymers used. Processes that use basic engineering materials such as plastics, for example FDM and SLS, have exactly the same recycling issues as would the larger community using these materials.
Photopolymers used in stereolithography and jetted systems, may have other issues, especially regarding the disposal of reactive, uncured resins. Theoretically, at least, once cured they should be very similar to the base polymers that are formed - typically these days acrylics or epoxies. The types of these base materials can be expected to expand, however.
The best - and possibly only understandable - sources of information on the fine aspects of photopolymers would be the companies manufacturing them and the few researchers in universities working under contract to these companies. You can find all those companies using directory resources on our site, and most of the researchers by using our bibliography.
Of course, the other great source of in-depth info is the patent system. However, deciphering that material is very difficult because much of it is presented in an intentionally obscure fashion, particularly for photopolymers.
The many other RP processes - and some of the above - also use things like paper, ceramics and metals of many kinds, etc. Three dimensional printing has its own cast of characters including starches, plaster and soon plastics. You can eat the starch (but don't), and I don't think there's much out of the ordinary that has to be done with plaster or the plastics. However, these materials are often infiltrated with adhesives to strengthen them. That's another amusement that deserves consideration.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Q2:
Are most of the fabber materials today recyclable?
A2:
***EG: To the extent that plastics and metals are recyclable, I believe the answer is "yes." Photopolymers - that needs to be looked at more closely. One interesting place to start is this patent:
6660208 Detoxification of solid freeform fabrication materials
Hanna; Stephen D. (Los Angeles, CA)
3D Systems, Inc. (Valencia, CA)
Some of the issues are the same as in detoxification. This patent and related works are aimed at making sure photopolymers are safe for applications like hearing aids.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
in 50 years?
A3:
***EG: One of the areas that are under strong development in the field of rapid manufacturing is composites - many types of materials put together in a myriad of ways. Find out a lot more in our section on the subject of rapid manufacturing. That's certainly where a lot of work is heading - and it represents a major recycling headache. It's tough enough to recycle with materials that are clearly labeled and generally of uniform composition. What happens when you intimately mix things using a complex gradient? Or you mix disparate materials like metals and ceramics? Little fun will be involved in trying to get these things apart. It may not be possible and wholly new approaches required. One good question is what do people do with composite materials today? Are they recycled? I have no idea.
These (and what I've described above) are the general trends for the next 5 to 10 years. In 50 years, I'll have the advantage of being dead and not having to worry about it - but I think a good guess is that materials technologies will merge with computation, electronics and other advanced technologies to
yield whatever is the thing after smart materials. You can get a glimmer of it in some of the work being done at MIT to develop futuristic soldier suits, and the mesocopic devices for airplane skins being worked on at Stanford.
Maybe in 50 years recycling is moot: Your additively fabricated composite sport coat need not be recycled because software downloaded from passing satellites by the coat not only monitors your every bodily function, but updates and incrementally reconstructs the color and cut of the jacket to reflect the latest style, alters its size to fit your burgeoning body, and repairs tears and rips using clotting-like processes. Required materials are absorbed from the air which has been seeded universally with gas molecules that form the raw materials for nearly all industrial and consumer processes, but are completely harmless and actually contain vitamins and smell nice. Active heating and cooling keep you comfortable in all seasons, and foreign substances are fought off using techniques like white blood cells fight antigens. This keeps the coat clean but larger spots and accidents are automatically removed by localized mechanical exchange of water vapor from the air. Detergents are synthesized in the process which is specific to the particular insult; samples of the detergent programming are sequestered locally for future use by the jacket because it now knows exactly what kind of slob you are, and what area you spill it on. The coat costs 1,000 Universal Credits which is the equivalent in today's money of just three cents.
As wacko as that sounds, it probably doesn't go far enough. Marshall will love it.
Section I: Introduction
Section II: Present
Section III: Future (YOU ARE CURRENTLY IN THIS SECTION)
Complete Table of Contents
Reference