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I keep polishing but the scratches remain

Hi. I am sanding down the frame of my motorcycle using the different grades of wet and dry sandpaper. The problem is that the sanding lines are still visible after every grade. Even when I get down to grade 2000 there are still visible sanding lines. Is this normal. What should I do. Thank you.

richard.

Richard Bergez
Hobbyist - sacramento, Usa
July 15, 2008

You have to go as close as possible to 90 degrees from the first paper to the second and so on. You go at the 90 degrees until the first set of scratches are no longer visible. When you think that it is, wipe it down with a paper towel and alcohol. You may not like what you see, but it can be done.

James Watts
- Navarre, Florida
July 17, 2008

Sandpaper 2000 indeed leaves visible lines. You need polishing compounds that go beyond to what even a 20/20 vision can trace. The less expensive ones are blends of Aluminum oxide from 15 microns or so down to 3 micron. They are used with rotary wheels or felts and come in bricks or sticks of different colors depending on their abrasive particle size. Polishers use them all the time to prepare parts for bright plating.

Guillermo Marrufo
Monterrey, NL, Mexico
July 21, 2008