Bill, I don't claim to be an expert in the field of over molding or potting electronics... but the first guy I would talk with in researching the molding of plastics in any form would be Bill Sandford at Hi-Rel Corp in Riverside Calif. He has done some work for me in the past and I recommend him highly. A very knowledgeable guy. Also, the potting of transformers and chokes would be cleaner if they were molded similar to the way axial leaded capacitors are over molded. I was involved with a leaded chip capacitor application where we used pelletized thermoplastic resin and injection over molded the capacitors into a DIP pattern for the '2 pin dip' style caps that have been replaced with surface mounted caps today, (lead-less). I know that Pico over molds their transformers for current sense applications.. A similar process should work for you. Figure to spend 10K on Tooling, and have a high volume application so you can amortize the cost of the tooling over the life of the product... If you have a low volume product, you may be stuck with the messy potting compounds for cost reasons... Hope that helps a little... ;) Bill Brooks PCB Design Engineer DATRON WORLD COMMUNICATIONS INC. 3030 Enterprise Court Vista, CA 92083 Tel: (760)597-1500 Ext 3772 Fax: (760)597-1510 mailto:[log in to unmask] IPC Designers Council, San Diego Chapter http://www.ipc.org/SanDiego/ http://home.fda.net/bbrooks/pca/pca.htm -----Original Message----- From: Kasprzak, Bill (sys) USX [mailto:[log in to unmask]] Sent: Monday, July 16, 2001 8:51 AM To: [log in to unmask] Subject: [TN] Recommendations for developing a mold Hello all, I am involved with a project that requires that I encapsulate a pc board in mold so that when completed, it will be a ring with an ID of 1.37" and an OD of 1.64". The ring will be .13" thick and .35" tall. There will be six, 28 AWG wires exiting the finished potted assembly. The potting compound will be Emerson & Cumings 2651-40 with Catalyst 11. I have a basic 3 piece mold that works OK, but the pieces only reflect what the final product should look like. It takes a little work to get the mold apart even though mold release is used. The cure for the potting is 8 - 16 hours at 180 deg F What I'm looking for is any tricks and hints that should be incorporated into the mold design that would facilitate easy processing. What I mean is to make it easier to pour the material, easy to assemble into the mold, easy to take apart, etc. etc. Right now the whole process just seems to be crude and messy. Maybe, that's just the nature of the beast. Any and all responses appreciated. Thanks. Bill Kasprzak Moog Inc., Electronic Assembly Engineering ---------------------------------------------------------------------------- ----- 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 the following message: SET Technet NOMAIL 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 the following message: SET Technet NOMAIL 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 ---------------------------------------------------------------------------------