Scratch in poly on walnut table before cured

It's hard to see and I think the photo isn't fully loaded yet because I can't expand it.

If you just finished it, I would probably sand out the scratch with 400grit wet sanding and add a final coat.

The other option is deal worth it because it will likely happen again with a kid around 😕

If you want to get rid of the scratch you would have to put another coat on the entire top. You could make it to where nobody would know it was there unless they were looking with Old English Scratch Cover for dark wood. Another option would be to rub the scratch with the meat of a pecan. You might as well do that, with children in the house furniture will get some scratches from time to time. The scratch would probably have occurred even if the finish was cured.

If you do choose to put another coat on whether now or next year be sure to clean the table with a wax and grease remover and scuff sand the surface first. Try not to use aerosol furniture polishes. They contain silicone which can make putting another coat of finish on complicated.

Dang that scratch is small. I know you want it to be perfect but from my experience with sons, it won't be for too long. I would suggest leaving it and lovingly remind him of it when he gets older. It is now a family heirloom.