Mike, Stay with 2 mil off for 20mil stencil apertures. Our 20 mil stencil apertures have 3mil off for gold plated boards and we use 5 mil stencil for all boards that have 20 mil QFP's. We still have more than enough solder for QFP pins. If you change to 1 to 1, definitely it causes more solder bridges and solder balls. Just one note, all reflowed solder joints have dull or gray-looking appearance. That's normal. Gold diffuses into melting solder causing dull or gray-looking solder joints. regards matthew NII-Norsat International Inc. >>> "McMonagle, Michael R." <[log in to unmask]> August 21, 1998 2:17 pm >>> Folks, We are converting an assembly from HASL to gold that has large quantities of 20mil devices. With HASL boards, we used a rule of thumb of 2mil off of aperture width on these parts, 1mil on each side. Based on the lack of pre-existing solder, should we go 1:1 on the gold board stencil apertures? One of our engineers is recommending this, but I am concerned about the possibility of bridging on 14mil wide pads. Our stencils are 6mil laser cut/electropolish. Any insights would be appreciated.... Mike McMonagle PCA Process Engineering Supervisor K*Tec Electronics 1111 Gillingham Lane Sugar Land, TX 77478 (281) 243-5639 Phone (281) 243-5539 Fax [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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################