Martin I agree with Brian Ellis and Jarmo Kiiski. Adding my thoughts, baking boards will also depend on the board material used. For example, polyimide boards absorb moisture very well. I've seen circumstances where polyimide boards were baked at 80C to 125C from 4 to 24 hours. Temperature and time was dependent upon the complexity of the boards (SMT vs. PTH), board thickness, and component density. In a prior life, I ran a study where on FR4 boards, I had the moisture content measured. After the measurements, I ran the material through an aqueous cleaner and measured the moisture content (Somebody was afraid that the boards would have to be for 24 hours baked after aqueous cleaning). Then I baked the boards at 100C for up to 4 hours. After the first hour, minimum moisture was found. Hope this answers your question. Good Luck. Lee Whiteman Senior Manufacturing Engineer ACI / EMPF Telephone: (610) 362-1200; Ext. 208 FAX: (610) 362-1290 E-Mail: [log in to unmask] -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Martin Christie Sent: Thursday, June 01, 2000 4:48 AM To: [log in to unmask] Subject: [TN] Baking of boards Hi Technetters, What is (or where can I find) the recommended bake parameters for baking boards before reflow? Martin Christie ACW Technology Ltd., Hylton Road, Petersfield, Hants. GU32 3XX Tel: 01730 300000 ext 146 Fax: 01730 266045 e-mail: [log in to unmask] ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - 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 1.8c ############################################################## 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################