I am using Taiyo AUS-5 on electrolytic nickel gold. Yes, we would like to do selective plating, but the parts cannot be bussed. We are required on this part to use electrolytic full-body gold & the Taiyo mask. Electrolytic gold is not very smooth when examined microscopically. There seems to be many cracks & crevices to get into & trap material. Matt Byrne HADCO ______________________________ Reply Separator _________________________________ Subject: Re: [TN] Re[2]: [TN] Soldermask developing Author: "TechNet E-Mail Forum." <[log in to unmask]>, [log in to unmask] at SMTPLINK-HADCO Date: 2/11/98 11:33 PM You did not specify whether your gold was electrolytic (usually a thicker deposit and less porous) or the electroless Ni/Au (usually thinner [up to 5 microinches] and more porous). I would expect that there would be no problems with developing mask off the electrolytic gold and there could be more problems with the more porous electroless Ni/Au. Most people who use gold circuitry will selectively gold plate (electrolytic) or will plate the electroless Ni/Au after the solder mask has been applied and cured. Let's face it, gold is expensive and the less you can get away with and still satisfy the customer, the better for the bottom line. I have not heard of developing LPI mask off of gold (not a whole lot of experience here, either). Perhaps, you may need to develop more aggressively or look at other LPI solder masks. Larry Fisher Dexter Electronic Materials [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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################ ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################