Furniture, Wood and Cabinetry Finishing - refinishing notty pine chest

I have a notty pine chest that I have removed the color with paint remover. I have put on 3 coats of stain and have sanded and cleaned after each process. Now that I have put on the polyurethane there are white streaks coming through on one piece. I have used thinner and water to clean and have waited until the next day to put the next coat on.

I took the piece to our local hardware store where I bought the Minwax products and he said he had not seen this before and thought that the water my not have dried. If I sand it and clean with thinner it goes away for about 30 seconds. I am at a lose to know what to do. Can you help?

Your friend at the hardware store was on the right track when he suspected water. What has happened is moisture has become trapped in the surface - probably from humidity. Why did it affect one piece and not the other? Your guess is as good as mine.

Unfortunately, with polyurethane, the only cure is to sand the white marks out. Use 400 grit wet/dry, lubricated with water. Sand until the piece (when completely dry) shows no sign of the white marks.

Finish the piece with applications of polyurethane with an aerosol - it's less likely to be affected by the humidity.