Fixing a coated PCB board

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I am trying to replace a toasted component on the printed circuit board in a Lincoln welder. The board is  coated with a heavy transparent coating, what I believe is called a conformal coating, that pretty well stops me from removing the solder and the bad component.Anyone know the best way to deal with this? I was thinking of using a tiny wire brush on a Dremel, but don't want to risk damaging the board.
Reply:See post #71http://weldingweb.com/vbb/showthread.php?t=92611&page=2Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:This may help: http://www.paryleneconformalcoating....gs_removal.htmA google search of "Removing conformal coatings" will bring up many other sites.Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:See the following url for a conformal coating removal pen. http://www.circuitmedic.com/msds/msd...emover_pen.pdf This link has much more information.http://www.circuitrework.com/guides/2-3-1.shtml
Reply:How thick is it and how old is the machine? The newer ones are potted and you can just dig out what your after.(Home)Miller Maxstar 152 (sold)MM211/spool gunLincoln AC 225C(Work)Dynasty 350Powcon 300STLincoln SP-175TWeldlodgic AWS150sWeldlodgic AWS300Custom Resistance seam weldersCambridge Vacuum EB weldersI smell something burning.
Reply:It's a SP135+, about 5 years old. Coating is about as thick as a heavy coat of paint,  very hard and crystal clear. Well bonded to the board and  won't peel. Toluol and MEK had no effect on it. I've been scraping it off with a Exacto blade, since its a triac there are only 3 legs to worry about. I may look for a tiny wire Dremel brush tomorrow. Or I may just cut the bad triac off its legs, leaving them soldered to the board, and solder the new one to them. Klutzy but avoids messing with the PCB.Last edited by kylemorley; 05-15-2013 at 10:16 PM.
Reply:We had a trace burn out of a Lincoln 140 mig about a month ago. It is a newer style machine, it had clear potting poured on the board. We dug it out and laid wire on top of it and repotted it. Worked like a charm. Good luck on your repair.(Home)Miller Maxstar 152 (sold)MM211/spool gunLincoln AC 225C(Work)Dynasty 350Powcon 300STLincoln SP-175TWeldlodgic AWS150sWeldlodgic AWS300Custom Resistance seam weldersCambridge Vacuum EB weldersI smell something burning.
Reply:I usually just use the tip of the soldering iron to burn through the coat and remove the component. Then I clean the area afterwards with a chisel tip dental tool and alcohol.