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How to Pre-finish Wood Trim Before Installation
Learn how to pre-finish crown molding, bead board and other wooden trim before installation.
Pre-finishing new wood trim such as crown molding, baseboards, bead board, and chair rails before attaching it to the wall has a number of benefits. Among those advantages are minimizing fumes by working in a well-ventilated workshop or garage, applying the finishes while you stand upright at a convenient work surface, and eliminating the likelihood of smudging painted walls or dripping on interior floors. You can apply multiple coats of stain and topcoat and allow them to dry at your convenience, thus keeping your interior living space clutter free until you are actually ready to install the trim. Nail holes present no problem, because they can be touched up with a wax finishing pencil that makes no mess whatsoever. Add the potential of using water-based finishing projects for easy soap and water clean up, and the entire project goes quickly and efficiently.
Step by Step Instructions with Video
Step
1
Purchase Materials and Assemble Tools
Purchase the required wooden trim and assemble your project tools and materials. This brief demonstration uses only a pneumatic brad gun and water-based finishing products, but your project may require both power tools and products that emit harmful fumes, so be sure to use appropriate protective gear such as safety glasses, a facemask, and gloves.
Step
2
Lay Out the Trim on Your Work Surface
Cover and protect your work surface with a tarpaulin or sheets of craft paper, as we did. Lay out strips of scrap wood in one direction and then set the trim at right angles to it to lift it off the work surface. The space beneath will facilitate coating the edges of the trim and minimize the amount of stain and topcoat lost on the protective cover. Having a dedicated workbench is a great help, but you can set up a temporary work area with sawhorses and lay the trim across them just as easily.
Step
3
Tear the Sand Paper Sheet into Quarters
Tear a sheet of 120-grit sand paper into quarter sheets. We use a home-built "jig" (a board with a sharp metal straightedge screwed down at each end) to rip the paper. Insert the paper underneath the straight edge and pull upwards against it to tear the sandpaper.
Step
4
Fold Each Quarter Sheet into Thirds
Fold each quarter sheet into thirds with the abrasive side outward. Folded to this size, the sandpaper conforms neatly to your fingers or the palm of your hand and, consequently, to the particular area of the molding profile that you want to sand.
Step
5
Use Thumb, Fingers, or Palm to Conform to the Sand Paper
Use your thumb against the sandpaper for smaller curved surfaces and multiple fingers for larger surfaces on molding. On bead board, use the sandpaper fold in the palm of your hand. Be sure to rub with the grain of the wood to avoid leaving scratches in the grain that will become more evident with the application of stain and topcoat.
Step
6
Sand Crevices with the Sand Paper's Folded Edge
Sand with the folded edge of the sandpaper to smooth grooves and crevices. Hold the folded edge flat against the wood rather than using a corner of the fold to avoid making nicks.
Step
7
Refold the Sandpaper to Expose a Fresh Surface
Refold the sandpaper to expose a fresh surface when necessary and to make good use of every inch of the sheet without waste.
Step
8
Remove Dust with a Tack Cloth
Clean off the fine dust left by the sandpaper by wiping the wooden trim with a tack cloth. Its sticky surface grabs the dust without making it airborne the way a brush or dusting cloth would.
Step
9
Choose Good Stain in the Desired Color
Choose a good brand of stain in the desired color to make the wood look its very best. We use a water-based product that permits soap and water clean up for hands and brushes.
Step
10
Shake the Stain Well to Mix It
Shake the stain well in its container to mix it and then pour a small quantity onto a clean wiping cloth for application. A cloth also works well for larger flat areas, but is limited for working stain into grooves or crevices.
Step
11
Use Long Sweeping Motions to Apply Stain
Use long sweeping motions to apply the stain, working with the grain of the wood. Wearing gloves is always a good idea when working with chemicals or foreign substances, but this stain will wash off with soap and water.
Step
12
Pour Stain into a Container to Use with a Brush
Pour some stain into a separate container (after shaking it to mix it) in preparation for using a paintbrush for larger areas, grooves, and crevices. Check the manufacturer's instructions to confirm whether optimum results require a natural or synthetic bristle brush.
Step
13
Use the Same Technique for Brushwork
Use the same technique for brushwork as you did for wiping the stain on with a cloth. Work with the grain in long sweeping motions.
Step
14
Wipe off Excess with a Cloth
Wipe off the excess stain with a soft clean cloth, regardless of whether you used a cloth or brush to apply it.
Step
15
Clean Up with Soap and Water
Clean your hands and brushes with soap and water before they dry. Let the stain on the wood dry for the length of time recommended by the manufacturer.
Step
16
Select Topcoat Product in Satin Or Gloss Finish
Select the top coat in the desired satin or gloss finished desired. We will use a wipe-on water-based polyurethane topcoat. Shake the topcoat well prior to use.
Step
17
Apply Topcoat with a Cloth
Pour a small amount onto a clean lint-free wiping cloth and coat the trim. You can also pour some into a pan, dip the cloth, slap it against the sides of the container to remove the excess, and apply it to the trim. With either application method, the topcoat seals in the stain, protects the surface, adds sheen or gloss, and gives the wood finish depth.
Step
18
Apply Finish in Long Straight Strokes and Work with the Grain
Apply the finish in long straight strokes and work only in the direction of the wood grain.
Step
19
Let the First Topcoat Dry
Let the first topcoat dry according to manufacturer's directions.
Step
20
Sand Out Imperfections in First Topcoat
Use 220-grit sandpaper between topcoats to smooth out dried air bubbles or particles caught in the finish.
Step
21
Quarter the Sandpaper and Fold Each Quarter in Thirds
Tear the sandpaper sheet into quarters on the home-built jig and fold it into thirds as you did for the first sanding pass.
Step
22
Sand with Light Pressure in the Direction of the Grain
Use light pressure and sand only in the direction of the wood grain.
Step
23
Remove Dust with a Tack Cloth
Remove the sanding dust with a tack cloth.
Step
24
Apply a Second Topcoat
Apply a second coat of topcoat/finish using the same application method as the first coat. Let it dry.
Step
25
Install Wood Trim on Walls with Pneumatic Brad Nailer
Install the wood trim with a pneumatic brad nailer.
Step
26
Fill Nail Holes with a Wax Stain Pencil
Fill the nail holes with a wax pencil that matches the stain color.
Step
27
Wipe Off Excess Wax
Wipe off the excess wax, once you have filled the holes.