Applying Grain Filler Onto a Wood Surface

As you gain experience in working with wood you will no doubt discover more about the characteristics of wood, including the wood surface, how to cut it, smooth it, glue it, and nail it. One of your discoveries might be about the wood grain, about when you'll need to fill the grain, and how to fill it. You'll likely learn about wood fillers, which ones work better with certain types of wood, and how to apply it. To learn more about applying grain filler to a wood surface, follow the steps below.

Things you'll need:

  • Wood filler
  • Sandpaper
  • Paint brush
  • Clean cloth
  • Scraper
  • Dry towel, or burlap
  • Stain or varnish

Step 1 – Filling Open Large Pore Wood

In choosing which type of wood you will want to work with in your project, you should not only consider the color of the wood, its hardness, and the characteristics of its grain, but the type of filler you will need to apply to your wood. Take into account that wood pores, like skin pores, are different in various types of wood. In open pore woods such as walnut, cherry, chestnut, hickory, etc., you will find a texture that is more rough. Plan for the pores in these woods to absorb more stain, giving these pores a darker shade than areas surrounding the pores. For these woods, plan to use a paste filler.

Step 2 – Small Pore Wood

For small pore wood (open grain wood), such as maple, aspen, sycamore, alder, etc., plan to finish your wood without using a filler. You'll find that, even without a filler applied, you'll get a finish with consistent color. Because of the small pores, your wood surface on these wood types will be smooth, without your applying fillers.

Step 3 – Test Your Filler Application

If you are a novice in working with wood fillers, you'll be wise to practice applying your fillers on scraps of wood, before applying it to your finished wood piece. Practice not only different methods of applying the filler but other steps such as sanding and varnishing. When you are satisfied with the results of your tests, then apply them to your project piece.

Step 4 – Applying Your Filler

Before applying your filler, lightly sand your surface to create a more smooth surface for your filler. In using a paste filler, mix the paste with your solvent (turpentine is usually recommended) to get a consistency like thick cream. Remember to stir thoroughly during initial mixing and during application. Apply the filler in the direction of the grain and against the grain, using a paint brush or clean rag.

Step 5 – Removing Excess Filler

Removing excess filler before it dries is an important step. Waiting until the filler dries will make removal a challenge. Before your filler's glossy appearance begins looking dull, use a terrycloth towel, burlap, or plastic mesh to remove excess filler. Apply strokes across the grain until all pores are filled and all excess filler is removed.

Step 6 – Finishing

When your filler is dry, lightly sand it again, then wipe away any dust or residue, and apply your choice of finish coat.