Poor Quality Roller Cover
One of the most common problems with roller marks is using a roller made of poor quality. These roller covers can cause textures and highly visible marks on the paint surface. Less-expensive rollers tend to be cut straight at the ends rather than the more expensive one that are beveled. The marks may not be visible until the paint is dry. This can cause unsightly blemishes and an unprofessional appearance.
Applying Too Much Pressure
While you are painting, if you put too much pressure or roll too fast, it can cause air bubbles or foam to get into the surface. Cheap rollers are usually installed on top of a cardboard outline. Once the roller gets wet with paint, the cardboard does too and it will lose shape. Because of this, it makes it difficult to maintain equal pressure while you are painting. The roller frame also is known to be a culprit at leaving roller marks. Inexpensive frames also have too much give and will paint unevenly. Higher quality rollers will not flex as much.
Paint and Splatter
Inexpensive paint also does not level well. After you paint, tiny bubbles will former and roller traces will not level, which can form roller marks. An additional problem is roller splatter, which can happen when you roll too fast. Some paints can also splatter more than others. Woven roller cover can reduce the amount of splattering than others. This type of roller will hold in the paint better and does not splash as much.
Solution
Purchasing higher quality roller covers can diminish problems with roller marks. After time, rollers can wear out and begin producing roller marks. When this happens, you should change the cover. Using a cover with a shorter nap length can help the paint be more leveled once it is applied. High quality paints with a high proportion of solid particles and binders can help with roller marks. Another solution, is painting in a zigzag pattern rather than an up and down movement.