Bob and Ken: We use temporary soldermask all the time. It's great for masking off any area of a circuit board that you don't want soldered. We use Kester TC-564-1 water soluble mask. We somewhat routinely bake for one to two hours at 90 - 95C. The baking that we do is tied to using HF-1189A water soluble flux. The boards are cleaned in a Trieber in line cleaner. I can't say that I've left masking on for 12 hours at 125C Bill Kasprzak Moog Inc. ############################################################## 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 Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################