I have 75 yr. old home. Previous owners have painted the dr. knobs

Soak the knobs in hot water to loosen many layers of paint. If you want to avoid nasty fumes and mess of chemical strippers, just fill a slow cooker with water and set the dial to high. Inspect the knobs every hour to see how well the paint is separating from the knob. When it looks loose, remove them from the crockpot and try to peel it loose paint off. Repeat as necessary.

Since the knobs and surrounds have been removed, simply give them a bath in paint/varnish remover for approximately 15 minutes. If there is a little left, simply repeat. The old finish will fall off. Now don't forget the rubber gloves at the beginning, and steel wool at the end. The steel wool should take care of any residue and or rust left behind. It's messy, but what re-habber isn't used to a little mess, and you'll be so proud of the results.

Soak them in paint stripper then use steel wool to sand them down

Paint stripper will work.

We watch the Home and Garden channel a lot. There is a program on there called "Rehab Addict". She flips old houses. She puts painted hardware in a crock pot on low overnight. The next day she takes everything out and cleans it with an old toothbrush. It works every time and sometimes there are more than just a couple layers of paint. I thought of her when I read your post. I hope this helps you. Good luck.

Yep, Nicole Curtis is who Aljosjer means and that is just what she does and it is super effective.