John, I refuse to say "in another life" because I have only one life to go through and learn through, taking credit for my successes and accepting responsibility for my learning opportunities. (to me it's a Dilbert "pointy haired manager" phrase(of course so is "learning opportunity" instead of mistake) (sorry for the soapbox)
BUT I have had the opportunity to investigate both conductive materials (composites) and conductive coatings. We decided to use conductive coatings on a computer system for a medical imaging system. The product was mature and only limited units were expected to be sold. We did replace some of the panels with metal ones (at a cost savings even over the unplated plastic! management liked that). A sprayed on copper paint was applied to the plastic parts. It worked very well! At the joints, soft gaskets (conductive fabric covered foam) were used (e.g. Schlegel (spelling?)). This reduced wear (assembly / disassembly) concerns. The unit went from being a "comb generator" to compliant. Adequate application of the coating was achieved. Vacuum deposition was considered but was too expensive and may have had problems with the cavities in the existing plastic parts. For the fairly small quantity of parts, this worked quite well. IF we were starting a project and could design the plastic parts with a particular process in mind, other processes (e.g. plating) might be a better choice. Refer to other comments on safety aspects. I have seen problems with coatings flaking off. Also note my experience occurred ~ 5 years ago. Seems recent to me but there may have been many improvements in the field since then. Good luck! Daren A. Nerad EMC Engineer 815.226.6123 -----Original Message----- From: John Juhasz [mailto:jjuh...@fiberoptions.com] Sent: Monday, August 20, 2001 1:30 PM To: 'emc-p...@ieee.org' Subject: Conductive Coatings Greetings . . . Beginning to consider conductive coatings for EMC shielding. To be used inside a plastic cover (material as yet unknown) in a low power/voltage (SELV) application. This is unfamiliar territory. I'm sure someone on this listserv has experience with these. I know to at least consider shielding effectiveness, material compatibility (plastic housing material to coating), and end-user environment. What are some other critical criteria? Thanks. John A. Juhasz Product Qualification & Compliance Engineer Fiber Options, Inc. 80 Orville Dr. Suite 102 Bohemia, NY 11716 USA Tel: 631-419-2324 (direct) Fax: 631-567-8322 ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall," ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
