I'll throw my two cents in. Assuming that you don't want to save the components you are replacing, I would advocate the dry thermal rework over chemical or microblasting. When you do the chemical stripping, you have a waste stream to contend with and chemical exposure to the operators. By their nature, urethanes are more chemically resistant (than acrylics) and require more aggressive agents to remove. Second, you will have a perimeter area around the device where you have a fringe of coating that has interacted with the chemical stripper. Is that combined material OK? Is it corrosive or conductive? Will it cause softening or attack of subsequently applied coating? How smart is your chemical? Does it magically know to attack only the urethane of the coating and not the urethane or acrylic that is in your solder mask? For the dry rework, you only have minimal smoke involved, and a simple fume extractor, as we use for soldering fumes, works well to protect the operator from any agents in the smoke. It is much quicker than chemical stripping and the pads clean up fairly well. Use of a hot gas rework station or proper rework tools minimizes the thermal shock to the board and pads. Now, if the undersides of your components have coating underneath cementing them to the board, you have another situation and you will probably have to chemically strip that coating anyway. And this advice is worth every penny you paid for it.... I now brace myself for the two dozen automated out of office responses....... Doug Pauls Rockwell Collins --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------