Comments on: Windshield spider web scratch removal http://www.thejoyofaviation.com/airplane-windshield-spider-web-scratch-removal A Private Pilot's journal. A conversation with friends. Sun, 27 Nov 2011 19:10:56 +0000 hourly 1 http://wordpress.org/?v=3.0.1 By: David Krump http://www.thejoyofaviation.com/airplane-windshield-spider-web-scratch-removal/comment-page-1#comment-25 David Krump Tue, 09 Dec 2008 19:38:13 +0000 http://www.thejoyofaviation.com/?p=91#comment-25 Great product report. FWIW, I used to work at an auto refinishing supply store (think auto parts but for body shops - selling paint, sandpaper, etc.). At one time, sandpaper did not come any finer than 600 grit. Then 3M came out with 1000 grit and others followes with 1200 grit. The 3M rep said there really isn't any standard measure for grit above 600, so those ultra-fine grit papers are really just marketing numbers. 800, 1000, 1200, pretty much all the same. They are all one step courser than polishing compound. If you really need to cut deep to get at the scratches, you are safe to start with 600, wet sanding of course, then follow with an ultra fine sandpaper. You could follow that with a wet cloth and cornstarch before starting your polishes. Cornstarch was what the old paint shop guys used before they came out with the ultra fine papers. Also, much better to use a random pattern orbital buffer than any other kind. I have one from Porter Cable that works pretty good, very similar to a DA sander from National Detoit with a counterweight for the random pattern. I can plug it into my 800 watt inverter, hooked to my car battery and polish my plane out on the ramp. If you use a pad on a drill, be very careful not to use too much pressure - not even enough to slow the drill - keep it moving always, and change pads often. Great product report. FWIW, I used to work at an auto refinishing supply store (think auto parts but for body shops – selling paint, sandpaper, etc.). At one time, sandpaper did not come any finer than 600 grit. Then 3M came out with 1000 grit and others followes with 1200 grit. The 3M rep said there really isn’t any standard measure for grit above 600, so those ultra-fine grit papers are really just marketing numbers. 800, 1000, 1200, pretty much all the same. They are all one step courser than polishing compound. If you really need to cut deep to get at the scratches, you are safe to start with 600, wet sanding of course, then follow with an ultra fine sandpaper. You could follow that with a wet cloth and cornstarch before starting your polishes. Cornstarch was what the old paint shop guys used before they came out with the ultra fine papers.

Also, much better to use a random pattern orbital buffer than any other kind. I have one from Porter Cable that works pretty good, very similar to a DA sander from National Detoit with a counterweight for the random pattern. I can plug it into my 800 watt inverter, hooked to my car battery and polish my plane out on the ramp.

If you use a pad on a drill, be very careful not to use too much pressure – not even enough to slow the drill – keep it moving always, and change pads often.

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