We haven't had a problem with paste on the back of the stencil. You may want to investigate your stencil printer to see why it isn't performing properly. We have an ultrasonic stencil cleaner that seems to clean solder off stencils very easily with a 2 minute cycle. Kathie Lambert Process Engineer Northrop Grumman Baltimore, MD -----Original Message----- From: Martin, Jesse [SMTP:[log in to unmask]] Sent: Monday, August 16, 1999 3:08 PM To: [log in to unmask] Subject: [TN] Solder paste stencils Has anyone had a problem with solder paste stencils that have a build up of solder paste on the bottom (PCB) side of the stencil that won't come off in the stencil cleaner? I think what happens is the vacuum/paper wiper leaves some on the bottom after each wipe and the more it wipes the harder it is to get off. I can pop it off with an Xacto knife or the like but is very time consuming. Only other thing that works is using a Scotchbrite pad but that leaves a lot of scratches (which probably causes faster build up). Have also tried stainless steel cleaner with no luck. We use an old Austin American batch aqueous cleaner with saponifier at 120 degrees F. Any and all ideas welcome. ############################################################## 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 ############################################################## ############################################################## 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 ##############################################################