We use a CMI CGX-B. It's an eddy current device, I believe. The catch is that you have to measure over bare copper and the unit has to be calibrated on the same type of subtrate (uncoated ) as you will measure the coating. Our process is conveyorized (horizontal)with a programmed robot sprayer. What I've had done is to have FR-4 cut up into 1/2 X 3/4" squares and have the operator place a square in an area that will be coated. After the drying oven, the coating on the square is measured using the CMI. The area where the test square sat is touched up. We have some designs that have bare copper areas left on the panel border for measuring and we've also used copper adhesive tape. Again, the key is to calibrate on an identical substrate. A certified thickness of mylar is used for calibration. I believe a beta back-scatter device would also be capable. George Carroll Process Engineer Siemens Energy and Automation Johnson City, TN [log in to unmask] -----Original Message----- From: Bissonnette, Jean-Francois [mailto:[log in to unmask]] Sent: Thursday, March 14, 2002 9:58 AM To: [log in to unmask] Subject: [TN] Coating thickness Hi All, Does anyone now of a technique or system to check conformal coating thickness after it's dry on production units? We have a positector to measure paint thickness on our enclosures but they're not design to work on materials like PCB. Jean-François Bissonnette Vérificateur, Contrôle de la Qualité Électronique Produits et Procédés Vapor Rail Inc. 10655 Henri-Bourassa O. St-Laurent, Qc H4S 1A1 (514) 335-4200 x2021 (514) 335-4231 fax <<Bissonnette, Jean-Francois.vcf>> WABTEC CORPORATION CONFIDENTIALITY NOTE The content contained in this e-mail transmission is legally privileged and confidential information intended only for the use of the individual or entity named herein. If the reader of this transmission is not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this transmission is strictly prohibited. ---------------------------------------------------------------------------- ----- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------