How to finish wood trim
It's so easy to give woodwork and trim a smooth, satiny finish every time with this simple three-day process. And you don't need expensive tools, special knowledge or skills to get a flawless finish - just sand, stain, seal and finish.
Discover how easy it is to finish all your wood projects perfectly. We show you how and when to sand, using the correct sanding products, how to apply stain evenly and without blotches on all the surfaces and the best ways to get a smooth satiny surface with sealer.
Believe it or not, finishing wood is not complicated, but it does require patience and attention to detail. It pays to get each step right the first time. Going back to correct mistakes is time consuming, and it's nearly impossible to achieve blemish-free results.
We recommend finishing your wood with one of the Woodoc range of products, as these sealers are formulated to be absorbed into the wood, and while varnish finishes are tough and have their place, especially on high-wear, water-prone surfaces like tabletops and hardwood floors, they're less forgiving to use.
Prepare by sanding
Preparation is the key to a good finish, and a good finish starts with sanding the bare wood with 80-grit sandpaper. This step is crucial for achieving a uniform wood surface that'll absorb stain evenly. It also smoothes out surface imperfections, which might show through the clear coat.
Your goals are to eliminate the sawmill “burnish” (shiny surface left by the cutting blade), smooth off any standing rough wood fibres and sand out any blemishes. Blemishes can include dirt, fingerprints, machining imperfections and label residue. Don't sand with finer grits at this stage or you're likely to end up with uneven stain.
The sanding tool you select depends on the profile and size of the trim you're finishing. For large areas or deep imperfections use a random orbital sander. It's aggressive enough to smooth quickly.
Sand tight cracks with folded sandpaper. The edge will wear quickly, so refold the paper often.
If you are sanding by hand, always sand in the direction of the grain and sand every square centimetre, whether you think it needs it or not. Your fingertips and eye will tell you when enough is enough. But look closely with good light before you call the job finished. Otherwise, imperfections like scratches caused by cross-grain sanding marks will become painfully obvious when you start staining.
Another common problem is burn marks. Sometimes extra elbow grease will be needed to eliminate those. This may sound like a lot of work, but believe me, if you use fresh paper and sponges, the sanding goes fast.
High-quality finishing supplies take the pain out of staining. An investment in good tools and accessories will greatly speed up the job and increase the quality of your finishing work.
- Sanding supplies. Buy 80-grit and 120-grit (medium) products for sanding the raw wood and either 180- or 240-grit (extra-fine) sanding paper for sanding between clear coats, depending on the profiles you're sanding.
- Brushes. You will need natural bristle brushes for staining, dry brushing and applying the clear finishes. Don't buy cheap brushes. If you take care of it and clean it well, a top-quality brush will last for 20 years or more. A cheap brush is more likely to leave brush marks and bristles in the finish.
- Only use lint-free cloths or rags. Mutton cloth will leave fibres behind.
- Gloves. A box of disposable gloves will protect your hands from solvents, and you won't have to struggle with putting on reusable ones after coffee breaks.
- Mineral spirits. Buy a 1 litre bottle to clean brushes and to thin stain if needed.
Clean the room
A clean work area is crucial for a smooth, blemish-free finish. If you have the option, sand the wood outdoors or in a room that's separate from the finishing area.
If you're forced to sand in the finishing area, wait several hours after sanding before cleaning the room, to give the dust a chance to settle out of the air. Use a vacuum that has water filtration to clean the floor and any nearby work surfaces. A water-filter vacuum extracts the dust and dumps it into the water rather than back into the air.
If you don't have a water-filter vacuum, use a damp mop to wipe floors and surfaces. Avoid sweeping—it just stirs up more dust.
Spread out stain-soaked rags and let them dry before disposing of them in a waste container. Piles of damp staining rags are a spontaneous combustion hazard.
Brush on the sealer and wipe it off fast
The key to getting an evenly stained surface is to saturate the wood thoroughly.
Start by gently stirring the sealer, scraping a paint stick across the bottom to pull up any settled solids and ensure that the stain is well mixed, then work them into the solvent until they're all dissolved.
The best application method is to simply dip a natural-bristle brush into the stain and brush it right onto the wood .
If the stain is absorbed very quickly - under 5 minutes - then apply more sealer until the wood no longer absorbs and the surface stays wet for 5 minutes.
Allow sufficient drying time for the first coat, possibly overnight, and then lightly rub down with steel wool.
This process removes any excess sealer left on the surface and allows the second coat of sealer to penetrate deeply.
Apply the second and final coats without any sanding but allowing each coat to dry thoroughly before applying the next coat.
For a high-gloss shine a fourth coat can be applied. However, bear in mind that this will also darken the final colour.