Removing Johnstones Smooth Masonry Paint From A Black Composite Door

First thing I would try would be using a sponge with a scourer and some slightly soapy water. See how that goes, otherwise use something that is *not* sharp to just push the bobbles off, you may be able to do this with your finger nail for example, making sure not to push too hard to not mark the door.

Try a citrus based cleaner like virosol. Spray it on a little area at a time. Let it soak for a minute or so, then use a wet none scratch scourer and sponge to work it off. Note- don’t leave the virosol on too long as it can be quite corrosive when neat & will likely take the coating off the door. And make sure you rince the door with clean water thoroughly afterwards. Or you could try methylated spirit.

Hot soapy water keep doing it till its all off

Use a mini grinder with a very fine buff pad on it

Make sure to get to it as soon as possible. Using a solution of warm, soapy water and a non-abrasive sponge, then leave to soak for few munites you should be able to scrub most paint away.

Firstly, as soon as you spot the problem try and resolve it straight away before it dries to much. I would use ultra grime multi purpose wipes, that are designed to soak up spills and clear paint. If this fails to remove the paint, i would get a dry cloth and dab it with white spirit. Then firmly scrub at the paint, you can also get a small scouring pad to help lift the paint ( don’t apply to much pressure with this). Then to finish wipe over with the ultra grim wipes.