Choosing the most appropriate tool will help you achieve superior results.
When it comes to smoothing wood, choosing the best tool for the job is the first step in getting the best results. The three main wood-smoothing tools at your disposal are sandpaper, scrapers and planes. Each has its advantages.
Good ole’ sandpaper contains tiny particles that scrape away imperfections and scratches. One advantage to sandpaper is that using it requires little finesse (unless you’re using a power sander) and therefore little practice.
You’ll need to start with a coarser grit and work through finer and finer grits (higher numbers, in the United States) to remove the scratches and imperfections the previous grit left behind. Skip a grit and you may see flaws. How fine a grit you end with depends on your project and the wood you’re working with.
Different sandpapers use different abrasive materials. Aluminum oxide is durable and often used for sanding wood. For a particularly smooth finish on bare wood, garnet sandpaper may work best.
One downside to sanding wood: It creates dust, which you don’t want to inhale. Wear appropriate respiratory protection, especially when operating powered sanding equipment. The dust can not only enter your lungs but also “clog” the sandpaper. “Open coat” sandpaper has more spaces between the particles and is slower to become clogged. “Closed coat” sandpaper is the most common.
To smooth wood faster and achieve superior flatness, a hand scraper, aka card scraper, is the better tool. Dirt cheap compared with other options (unlike sandpaper, you buy it only once), a hand scraper is nothing more than a thin piece of steel, usually rectangular, with a sharpened edge, or blade. A cabinet scraper is a hand scraper mounted in a frame, with screws for adjusting the blade. Pushing the blade slices off very fine wood shavings, leaving a perfect, smooth finish, no scratches (and no dust).
If you’re planning to stain or vanish the wood, scraping or planning may produce more clarity and contrast than sanding.
The key to using a scraper effectively is sharpening and honing the blade and then creating a “burr,” a minuscule lip or hook at the edge of the sharpened steel that becomes the cutting edge and makes smoothing wood easier. One way to create the burr is with a tool called a burnisher.
Scrapers tend to lose their edge quickly, so be prepared to re-sharpen and re-burnish as necessary. When the shavings left behind become more like dust, it’s high time.
Conventional wisdom calls for using scrapers on hardwoods only, though some people use them on softwoods, too. Be prepared to put some elbow grease into the job — scraping can be tiresome.
More expensive than scrapers, hand planes can be used for a variety of jobs, from smoothing wood to cutting down stubborn cabinet drawers and door frames to creating more level surfaces. Available in various lengths and sizes, planes can flatten and smooth surfaces to the point of perfection. Pushing the plane creates wood shavings at the back of the tool.
One key to using a plane successfully is starting with a finely sharpened blade. Some planes have adjustable blades. Until you know how deep you can cut without tearing the grain, start with a shallow blade setting and gradually increase the depth as necessary.
This video has tips on how to grip and use a plane with good results and without getting too tired.
Power planers can get the job done faster, but they’re not appropriate for all tasks, and many experts agree it’s a good idea to master the hand tool first before graduating to a power tool.