What does I use to remove the paint from an old door?

I bought an old door and am trying to fix it up. It's got some paint on it now, but it peels off and when I use the sander on it it gets sticky like its not dry. I'm thinking the person before mixed oil based paint with latex paint. I need to know what to use to get it all off so that I can pain it correctly.What does I use to remove the paint from an old door?
sand it or use a liquid paint remover on itWhat does I use to remove the paint from an old door?
i prefer to use heat to remove paint some like a heat gun but i prefer to use a blow torch it takes it down to the bare wood quick i use a hard putty knife to take the paint off. here are the steps i recommend work a 6 inch by 1 foot area. take the blow torch and warm the paint then go back over it until the paint starts to blister don't start it on fire. then take the knife and scrap the paint one swipe and it is off. a door should take you about an hour to an hour and a half hope this helps and do this outside.
buy a painters 5 in 1 tool or any razor scraper, and scrape off as much paint as you can before you sand. Are you going to repaint it? then scrape to remove any loose paint and then prime and paint. no need to sand or strip completely.