There are many things that can go wrong when painting. You can end up with drips, stains, a gritty finish, or other problems. We are going to go over the three problems mentioned and how you can fix them:
Drips are caused by too much paint being applied, this can be from a brush or roller that was overloaded with paint.
To remove a drip you will need:
A paint scraper
Paint in the color of what you are working on
Use your scraper to scrap back the drips so that the surface is even. Then sand the area to a smooth finish. Now you will repaint the sanded area.
Stains can be caused by several different factors, if mildew is what caused your stain you will need to fix the underlying problem before fixing the stain.
To remove a stain you will need:
A paint prep cleaner
Stain blocker or oil based under coat
Top coat in the color that is on the rest of the wall
Clean the area thoroughly with the paint prep cleaner and allow to fully dry. Using a paint brush, apply the stain blocker or oil based undercoat. Once this is dry you can then apply the topcoat.
Fixing a Gritty Finish:
A gritty finish can be caused by old paint that was not sieved or by a poor prep job.
To smooth a gritty finish you will need:
Lint free cloth
Topcoat in the color that matches your walls
Sand the gritty area down so that it is smooth. Using a lint free cloth, clean the area so that it is free of dust a debris, allow to dry. Repaint the area with the topcoat. If it was your paint that caused the gritty area, be sure to sieve the paint. Some people have found that running the paint through a pair of old panty hose into a new paint bucket helps to remove all the debris.