Refinishing a pine table. Applied one coat of minwax wipe on then sanded as told. Applied second coat and sanding marks still showing. Can it be fixed?
The simple answer in my thinking, is yes, it can be fixed but with caveats.
Sand, apply more, sand, apply more until you're happy. Of course you risk adding more scratches.
As others suggest, scratches come in all sizes. Sandpaper, luckily also comes in all sizes from Course (50 grit) to very fine which can go above 12,000 grit. The more grains of grit, the smaller they are, and the finer the scratches they leave.
Part of the equation is what are we sanding/finishing? Oak for instance doesn't to my eye get much advantage past 320 extra fine sand paper. Rosewood, in contrast, I've taken to 2,000 and can see a great difference from 320 to 2,000. Always move from lower numbers to higher numbers, and a good rule is don't go more than double in any one phase - 200-400, 400-800, 800-1600 as example.
Different woods are harder or softer meaning that the scratches embedded are deeper or shallower. Pine is soft, and will scratch very easy (dents easy too). If the underlying wood was not sanded to your satisfaction, then any finish will likely telegraph that to the surface.
The bottom line in my mind is sand as much as you feel proud of the end product. If the product is utilitarian, then maybe not as much. If you think it's heirloom, then maybe more. Use "raking" light to see the scratches and remove them with finer and finer grit sandpaper. Raking is a low angle, glancing light that makes the valley of the scratch stand out. Sorry to say, it's mostly a question of how much time do you have to dedicate.
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