Hi Brett- You can purchase the C/I/C cores from a TI (Texas Instruments) located in Attleboro MA. Unfortunately I don't have a phone number, but if you have access to the web, you can get the number from www.switchboard.com, or from www.altavista.digital.com, to name a few. TI manufactures the cores, but only plate to 1 and 2 oz thick. I'm sure you can get a plate shop to increase the thickness per you specific requirement, probably even TI. Unfortunately, I'm hearing that they may soon stop manufacturing the cores, so please, if anyone knows of another source lemmkno! Regarding the insulating filler material. Try "Howefill". This material is manufactured by Arlon, located in California. Again, sorry but I don't have a number (see above for phone search). I don't have the numbers, 'cause we're not using these materials, as it's not needed in our computer systems. However, the cross sectioning I've done for one of our customers', using these materials - fun stuff!! Good luck. Garry Morand Senior Lab Analysis Engineer Digital's Engineering Test Services Labs Digital Equipment Corporation 200 Forest Street Mail Stop: MRO1-3/D2 Marlboro, MA 01752-3085 Phone: 508-467-3107 Fax: 508-467-6796 Email: [log in to unmask] -----Original Message----- From: BA754 [SMTP:[log in to unmask]] Sent: Friday, May 08, 1998 9:51 AM To: [log in to unmask] Subject: [TN] Copper-Invar-Copper Technetters, We need to obtain Cu-Inv-Cu .040" with 6 oz Cu on both sides. Can anybody tell us where we can find this material? We also are in need of the insulating filler for the Cu-Inv-Cu core clearence holes. TIA Brett Austin Nationwide Circuits Inc [log in to unmask] ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################