This week's tip is from Mdog and tintefx
Quick tip. Some of you may already do this, whenever you clean windows, whether it be commercial or auto and you run into older gaskets with years or miles of contamination in them, try dry scraping the edge right up next to the rubber or felt without your spray solution. Of course a SHARP razor blade is in order, but by eliminating fluids it'll pretty much do away with any drip down of dirt since you wont be putting any type of irrigating effect on the gasket part. I do however slightly moisten a lint free towel and wipe the edge down before install. Just a thought...
Dry scraping is something I do also, I take a large paintbrush and cut the bristles about half, this makes the bristles alot stronger and you can basicly sweep the loose junk from around the seal, this method works very well on old painted and metal frame windows, after you dry scrape the edges and sweep the residue off you can then wet scrape it and continue as normal.