If you want to strip a painted door back to the wood, the easiest thing is to get it professionally dipped and stripped, but if you’d rather do it yourself and don’t fancy playing with harsh chemicals, you’ll need a good heat gun.
It should be lightweight and comfortable to hold and have a long power lead.
Try to get one with more than one heat setting so that you can avoid scorching the wood.
You will need a sharp metal scraper.
It is safer to remove the door before stripping it, this has the effect of making sure you don’t damage surrounding floors and decorations.
It also means that you won’t have the smell of hot wood and paint throughout the house and if you were to accidentally cause a fire it could be quickly and easily contained without causing further damage.
Remove the hinges and all fittings from the door.
Play the hot air from the gun over the paint in small areas until it starts to blister and then use the blade of the scraper to remove the lifted paint.
Hold the scraper so that the blade tip is square to the wood and apply moderately firm pressure while driving the blade away from yourself. If the blade tip is not square you could gouge the wood. Work along the grain of the wood, not across it wherever possible.
Do not blow the hot air over your hand or point the gun at other parts of the doors while scraping the warmed area.