How to avoid brush marks when painting? January 27, 2009
Posted by admin in : Painting Tips , 1 comment so farHow to avoid brush marks when painting?
Some paint-works look great from afar - fresh paint, strong colours, sharp edges - but as you approach nearer, imperfections in the form of brush
marks become obvious. It is a very common problem, and much more obvious on glossy surfaces than on satin or matt ones. This is because brush marks form undulating profiles that reflect light unevenly. If the paint used is glossy, the unevenness is exaggerated.
In an earlier post, I gave some ideas how brush marks can be prevented (see post - Method of Painting - By Brush). Basically, we need to watch 3 aspects of our painting - the brush, the paint and technique.
The Brush
A bad brush in the hands of a professional and with the best paint will give mediocre result at best. It is always good to pay 
more for the brush. Not only does it give you a quality finish, it also saves you time and a lot of frustration. Aside from the problem of brush marks, a low quality brush tend to open up at its sides, making painting of clean edges an impossibility. Then there’s the problem of bristles dropping and sticking onto the painting surface.
To avoid brush marks, always choose bristle that are relatively soft. The length of the bristle should preferably be at least 2 inches or longer. Short bristles tend to be harder at the ends and can cause brush marks easily.
The Paint
Choose paints that have a certain amount of "body". In technical terms, we refer to this as volume solids. All else being equal, paint with higher volume solids tends to self-levels better, resulting in less brush marks. Another point to note about the paint is its ability to flow easily. If the "flow" is poor, brush strokes will not be smooth, again resulting in brush marks. This problem can usually be solved by thinning with the recommended thinner. Lastly, find out about the drying time of the paint. Extremely fast drying paint (dries in minutes) does not give us time to smooth out any brush marks. Many nitrocellulose-based paints fall into this category and are poor candidates for brushing on. The alternative is to spray on such paints.
Technique
Load the brush with enough paint. As mentioned in the earlier post, dip only 1/3 the length of the brush (see picture on the left) into the paint and lightly touch the inner side of the paint can to drain off some excess (but not too much). Apply and distribute the paint with horizontal strokes before smoothing it out with light long strokes, lifting off lightly at the end of the stroke.
If all else fails, use a roller !
