Get a sharp cabinet scraper. Two or three actually each a little smaller than the last. A long scraper can be bowed slightly to take wood off only in a specific area. A scraper will take off a much or as little as you want and will never tear out wood. It will not gouge, scratch, tear, chip, or otherwise damage wood. It must be SHARP to work well. It will remove any coating, flatten the surface and leave a pure wood surface and a glass smooth surface. No solvents, wetness, spreading of contamination or fuzzy surface like sandpaper. I had a key frame that would not shut up its groans, squeaks and pops and I used everything. I finally got my scrapers and cleaned the frame and the keybed and it has worked just fine since. Scrapers are ancient tools that have gone out of favor because they require skill to prepare and sharpen them and a little skill in using them. You need is very small and easy to do. Scrapers will leave a surface glass smooth and ready to finish. When my butcher block bench top gets dirty and covered with glue and other contaminates I use a scraper to clean and resurface it. Newton
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