Paint Wood
You might think aside from walking and maybe riding a bike, painting wood would be a close third in the "things that are really easy to do" category. This might be the case if the wood you are painting is attached to an old barn. When setting out to paint wood, however, you have a couple of options: do it well or do it sloppy. You should strive to do the best you can, so with a little patience and a good technique, you can paint wood as well as any professional.
Contents
Steps
Preparing Wood for Painting
- Take your time to prepare the wood for painting. This is probably the most overlooked part of painting wood, and in many ways is the most critical. Your work is only as good as the canvas upon which your creation takes life. Paint will not fill in cracks, dents, holes or other imperfections in the wood and keep them hidden after it dries. In fact, those imperfections will probably be even more apparent.
- Remove any old paint from the wood as necessary. If the wood you want to paint has paint already on it, you’ll want to remove that paint before adding a new coat. Take a putty knife and scrape away as much paint as you can without getting too persnickety about coverage; don’t worry, you’ll sand away smaller flecks of residual paint before the preparation is done.
- Unless the existing surface is an oil based stain or finish, do not use chemical strippers. Scrape as much off as possible and then use a trisodium phosphate (TSP) solution to clean off the rest of the loose paint and grime. Rinse well.
- If your wood is treated with a stain or a finish, apply TSP to the wood. Instead of trying to remove the stain or finish entirely, focus on cleaning and sanding it (more on sanding later) in order to give the paint a porous surface to adhere to.
- Fill all dings and deep gouges with quality wood putty, if possible. Use a flexible putty knife and fill in all the areas needing attention. It is better to use too much in this step than not enough. You will sand down the area after it dries and hardens, so it doesn't need to be perfect at this step.
- Use regular spackle or joint compound to fill in small or shallow scratches. Wait to dry completely before sanding.
- Caulk areas of long and deep cracks. Use a tiny bead of caulk, smoothing it out well. Wait to dry completely before sanding.
- Sand the surface of the wood with coarse sandpaper and finish off with fine sandpaper. Start by sanding down the area where you've used putty or filler before moving to the rest of the surface for an even feel. Use a fine grade sandpaper for this work sanding the wood with 80 to 100 grit sandpaper, making sure to remove any paint that’s still on the surface. Finish off with fine 150-grit or higher to smooth out the surface and get it ready for priming. Remember to work the sandpaper with the grain of the wood, not against it, and to keep power sanders moving.Sanding tools:
Random orbital sander: Powerful but expensive, requires sanding disks.
Sheet sander: Less effective, but cheap and uses regular sandpaper. Best on flat surfaces.
Sanding block: Very labor-intensive. Not recommended except on small projects or for finishing touches. - Clean off any dust or wood residue with a clean towel. If you have a vacuum, vacuum off the wood thoroughly, followed by a sweep with a damp cloth. If you don’t have a vacuum, wipe off the dust or residue with a dry cloth, finishing off with a damp cloth. Wait for the wood to fully dry.
- Paint or primer won’t adhere properly to dirty surfaces. Paint does its job best when the surface that you apply it to is clean.
- Tape off any parts of the wood that you don't wish to paint. If you want a section of the wood to remain unpainted, or you want to paint a section of the wood a different color, you'll want to use tape to cover the parts of the wood you don't want to paint. You can get specially-treated tape designed for latex paint, like Frog Tape, at most hardware or home repair stores. These kinds of tapes adhere to wood well and are designed to minimize paint seeping into the pores of the wood.
- If you want to leave parts of the wood unpainted, you'll want to tape off at this stage of the prep. If you want to paint the wood different colors, you'll want to tape off after you've primed all the wood and painted specific sections.
- Prime the wood. Primer helps paint achieve a uniform, rich look on top of wood. Apply several coats of primer for the most even look in your final product. If priming raises the grain of the wood, consider sanding with a fine-grit sandpaper before the final coat of primer.
- Which color primer should you use? Use grey primer for darker coats of paint and white primer for brighter coats of paint.
- Should you use oil-based vs. latex-based primer? For many years, professionals instructed painters to use an oil-based primer on wood and follow it up with latex-based paint. That logic is slowly being turned on its head. Oil-based primer adheres to wood better, but it's also less flexible than latex primer, which means it's more susceptible to cracking. Especially if you are painting wood outdoors, latex primer is probably your best bet. Unless the type of paint you want to use specifically requires oil-based primer, use latex-based primer for most cases.
- Should you use a spray primer or brush-on primer? It's mostly a matter of preference. Spraying is easier and faster, but it usually requires several coats to get good coverage. Brushing is slower and more painstaking, but creates a thinner, more even layer of primer onto which to paint.
(Be sure to wipe off excess residue before applying the final coat of primer.) Follow instructions on your primer when calculating time between coats as well as the number of coats.
Painting the Wood
- Choose your type of paint. Most home paint jobs today rely on latex (water-based) paint. Aside from a handful of scenarios, this is probably the type of paint you want to use when it comes to wood.Alternatives and additions:
Oil-based paint: a durable coat good for heavily used items. Dries slowly, leaving fewer brush marks.
Conditioner or Extender: Add this to latex paint to slow down drying and reduce brush marks. - Choose a kind of sheen for your paint. Sheen, or gloss, is the amount of light reflected in your paint. High-gloss paints will appear to shimmer when exposed to light, while matte paints will absorb light and hide imperfections. When choosing a paint, look for descriptions of sheen and buy accordingly.Common types of sheen:
Flat: non-reflective finish good for hiding imperfections
Matte: very slightly reflective. Easier to clean than flat but not as much as more reflective paints.
Eggshell, Satin: increasingly more reflective. These tend to vary greatly by manufacturer.
Semi-gloss, Gloss: the most reflective and durable sheens. - Whatever kind of paint you choose, use high quality paint and brushes. It doesn't help to be cheap with paint; any savings you get by choosing cheaper paint will be sunk when the paint under performs and you need to buy supplies for a whole new project.
- Some people might be tempted to use a foam brush for their projects, but foam brushes give the painter less penetration and more air bubbles than bristle brushes. A high-quality bristle brush should blow a foam brush out of the water.
- Load your paintbrush with paint. Submerge about a third of your paintbrush into your chosen paint. Tap the paintbrush on the side of the paint bucket, turn the paintbrush 180°, and tap the other side of the paintbrush against the bucket. You should have a fully-loaded paintbrush with just the right amount of paint for good coverage.
- With a loaded brush, start from the top of the wood and move down. Brush evenly using somewhat shorter strokes. Repeat this three to four times until one segment of your wood is fully covered. Try not to let the paint stand very long between coats.
- Use an unloaded brush to pull the tips across the paint. This process is called tipping, and it helps you get good coverage while minimizing brushstroke appearance. The brushstrokes will flatten out as the paint dries, which is one of the reasons why slow drying paint is important.
- Wait for the paint to dry fully before repeating the process one to two more times. Depending on the paint you're using, as well as the finish you want to achieve (some people want the grain of the wood to stand out; others don't), you probably want to apply more than one coat. Before the final coat of paint, work over the dried painted surface lightly with a very fine sandpaper. This will give your final coat a nice surface to grip onto.
Sealing or Protecting the Finish
- Determine if you need a sealer or clear topcoat to preserve the paint on top of the wood. Many paints nowadays contain protectants that safeguard the paint against water and wear, for example, meaning you don't have to spend extra time applying protectants to your dried wood surface. Some people, however, may want to add an additional layer of protection between the wood and the weather, especially if the wood will be outdoors.
- Certain kinds of sealers or topcoats may not interact well with certain kinds of paints. Latex-paint, for example, is meant to breathe and dislikes some sealers. If you are unsure whether you need to seal your paint, or what sealers work with which paints, ask a representative at a local paint or hardware supply store.
- Prep the surface of the painted wood by lightly sanding and vacuuming off any paint residue. Prepping the painted wood in this way should not visibly affect the sheen of the paint or the evenness of the tone.
- Apply up to three coats of sealer or topcoat of polyurethane, depending on your preference and topcoat directions. Wait for the sealer or topcoat to dry, and sand if instructed. Repeat until the desired consistency is achieved.
Tips
- Use a stiff putty knife for your scraping work and use a flexible one for your putty work.
Warnings
- Wear protective clothing and eyewear when working with TSP. It is a strong cleaner that can causes irritation and burning of the skin. Rinse all areas in contact with TSP thoroughly.
- Wear a respirator when sanding and scraping wood. Old wood especially, may contain lead and this is hazardous to your health.
Things You'll Need
- Stiff putty knife
- Flexible putty knife
- Multiple grit sandpaper
- Caulking
- High quality paint brushes, various sizes
- Good quality paint
Related Articles
- Paint Wood Crafts
- Paint a Barn
Sources and Citations
- http://www.woodworking-news.com/woodworking-tips/random-vs-sheet-sanders.shtml
- http://www.bobvila.com/articles/30124-dream-it-do-it-how-to-paint-wood-furniture/#.U81rBI1dW-I
- http://www.lowes.com/projects/paint-stain-and-wallpaper/primer-buying-guide/article
- http://www.mlive.com/living/kalamazoo/index.ssf/2011/04/latex_vs_oil-based_paint_wood.html
- http://www.diynetwork.com/painting/differences-in-water-based-oil-based-and-latex-paints/index.html
- http://www.familyhandyman.com/painting/tips/trim-painting-tips/view-all
- http://www.elledecor.com/home-remodeling-renovating/home-renovation/advice/a2777/different-types-paint-finishes/