• Thick paint is subject to runs.paint image by jeancliclac from Fotolia.com
  
  The thickness of paint is an important factor in the final results of any painting project. If paint is too thick, the brush will leave unsightly streaks in the surface. If the paint is too thin, it will run. When you desire a thick coat of paint on the surface, the best way to achieve this is to paint multiple coats, waiting for each coat to dry. Trying to lay paint on in a single thick coat will almost certainly result in runs.
  
  

Rounding

• If you want to lay paint thickly onto a sharp edge to round the edge, you can, although the surface will probably require a large number of coats. You're better off rounding the edge before painting it if your goal is to take the edge off. You can round a wood edge with a small block plane or a piece of sandpaper. Blunt a metal edge with a file. If you must round the edge using paint, don't attempt it in a single coat. Continue adding thin coats and allowing them to dry until you achieve the necessary rounded shape on the corner.
  
  

Chipping

• Depending on the material you're painting and the quality of the paint, a corner that is built up with paint is subject to chipping if exposed to abuse or heavy wear. Particularly if it is brittle oil paint on a metal surface, the sharp edge on which the paint has been applied may cut through the paint when the surface is hit with something, causing chips to break off. Keep some paint on hand to repair this problem if it occurs.
  
  

Running

• If the edge that you are painting is irregular, it may cause the paint to run. As you apply the paint with a brush, a larger amount of paint will remain in spots on the edge where the brush has scraped across at a more acute angle, and the heavier areas of paint will run downward in accordance with gravity. When you are painting an object that is movable, position it so that the edge you are painting is horizontal to lessen any problems with drips forming. Don't thin the paint any more than absolutely necessary, and don't make the coats too thick.