different paints require different paint removers. was it water based house paint, enamel, lacquer, other?
usually a product advertised as a paint remover will do the job, time is relative, when the paint starts lifting or bubbling up, and stops it's time to start scraping, washing, etc. Many times, multiple attacks are necessary. In other words, you basically have to observe what is happening and play it by ear.
I like the water based removers, many times hitting it with a high pressure water spray will save you a lot of scraping, buffing and sanding. As I said before, I also like a product that sticks to the paint and does not fill the air that I breath or get in my eyes.
Be careful.