Some types of wood have grain with many open pores. Oak is a good example. The pores show through finishes and are especially noticeable under paint. It’s OK to leave the grain showing, but if you want a smooth, grain-free look, you’ll have to fill the pores before painting. There are a few methods. You can apply several coats of a high-build primer, sanding between coats until the pores are filled. Or you can fill the grain with spackling as shown here. If your cabinets have a lot of curves ...
