If you buy something through a link in our posts, we may get a small share of the sale.
Sanding rough wood removes imperfections, reveals the natural beauty of the grain, and prepares wood for finishing. In this article, learn everything you need to know about sanding rough wood, including how to prepare for the job, the correct order of sanding paper to use, and tips to achieve a perfectly smooth surface from even the roughest wood.
How to Prepare to Sand Rough Wood
- Assemble your materials. To sand rough wood, removing imperfections and getting it finish-ready, you will need; a belt sander and/or random orbital sander, sanding belts or sanding discs, sanding paper and a sanding block. A shop vac or household vacuum is also useful for cleaning up sawdust, as is a tack cloth to remove any dust clinging to the wood. If using a battery-operated sander, make sure the battery pack is fully charged.
- Choose a sander that connects to a shop vac, if possible. Most power sanders come with a filter bag to collect sawdust as you move along. These need to be emptied and replaced frequently for the power sander to work at its maximum capacity. Some power sanders can also be connected directly to a vacuum hose, saving you the time and effort of changing out or emptying the filter bag.
- Choose your workspace. Sanding outdoors is convenient as long as you have a dry space to work and the weather is comfortable. You will also need an appropriate outlet to plug in the vacuum, and the power sander if you’re using a corded variety. If sanding indoors, aim for a contained space with a filtration system, or vacuum up sawdust as you work to avoid spreading it all over the house.
- Protect yourself from sawdust. Avoid inhalation of sawdust particles by wearing a simple dust mask. Goggles or even safety glasses will help prevent sawdust from becoming lodged in your eyes. If you have long, thick or curly hair, consider tucking it under a cap so it doesn’t become clogged with sawdust.
How to Sand Rough Wood
Once you’ve chosen your work area and obtained your materials, you’re ready to get to work. Follow the steps below to turn rough wood into a smooth, project ready material.
- Begin sanding with low-grit sandpaper, in the 40 to 60 grit range. Grit refers to the number of abrasive particles stuck to the sanding paper. The lower the grit number, the larger those particles are, and the rougher they will be on the wood. Low-grit sandpaper, in the 40 to 60 range, will remove deep scratches and unevenness, but may add shallow scratches in the wood. Don’t worry about this, as you will remove those scratches in later steps.
Sand until the surface of the wood appears relatively even and major scratches, gouges, and dents have been removed. The wood will not feel smooth to the touch. Since this is the most labor intensive part of the process, it is recommended to use a power sander. Either a belt sander or random orbital sander will work well.
- Clean up the sawdust. Most of the debris generated during this project will come off the wood while sanding with low-grit sandpaper. Use a brush and dustpan, shop vac, or vacuum to clear up the bulk of the dust. You may need to clean the filter of the shop vac or empty the vacuum bag/canister when you’re done. At the very least, thump the filter with your fist or bang it against a sturdy surface to prevent the filter from becoming clogged with sawdust.
- Continue sanding with medium-grit sandpaper. This kind of sandpaper has a grit between 80 and 120. Use a random orbital sander for this step if you have one, as it will save you significant time and effort over sanding by hand. A belt sander is too powerful for this step. Stop when the surface of the wood feels smooth to the touch and the scratches left by the low-grit sanding are no longer visible.
- Optional: clean up the sawdust again. If you’re working indoors and don’t want to find sawdust all over your home in the coming weeks, it’s a good idea to take another pass with the vacuum. If you’re working outdoors, you can easily wait until after the next step to clean up the dust generated with medium-grit sanding paper.
- Finish with fine-grain sandpaper. Sanding paper between 150 and 180 grit is generally considered to be fine grain. Switch to a sanding block for this step, especially if you’re working with softwood. A sanding block spreads the pressure more evenly across the surface of the wood than scrubbing at it with folded sandpaper, resulting in a smoother, more even finish. Take your time with this step, working in sections. Stop when the wood feels very smooth to the touch.
- Optional: use extra-fine grain sandpaper. If you plan to apply lacquer, consider sanding with 220-grit sandpaper first. Lacquer is a high-gloss finish that will show even miniscule imperfections or unevenness in the base layer. Because it goes on so thin and reflects so much light, these defects will carry through to the final product. A super-smooth finish is therefore advisable if you plan to finish the wood with lacquer. Sanding thicker finishes like varnish, including polyurethane, are generally more forgiving, so this step might not be necessary.
- Remove all traces of debris from the wood. Sweep or vacuum up all visible sawdust. Use a tack cloth to wipe your work surface first. Then, wipe the workpiece, using fresh tack cloth if necessary. Tack cloth will not only remove sawdust, but any other dust clinging to the wood’s surface, and will prepare it to accept any kind of finish.
Rough Wood Sanding Tips
Wood that has already been finished may not need much more than a light scuff to prepare it for refinishing, but rough wood needs a lot more work. Follow the tips below to easily and painlessly take your wood from scary-rough to super-smooth and finish-ready.
- Sand in the same direction as the grain. Different types of wood have different grain patterns. Sanding parallel to the grain is more important on the last step of the process, using fine-grit sandpaper, than it is when removing deep gouges and scratches using low-grit sandpaper.
- Let the tool do the work. Avoid pressing down on your power sander. It increases the likelihood of mistakes. Not only that, it places undue pressure on the machine and wears out the sanding paper more quickly.
- Avoid mistakes. Improper sanding technique results in swirl marks or pigtails, which are coil-shaped marks across the surface of the wood. Random orbital or dual-action sanders are the most likely culprits. Debris between the sanding paper and the wood (including excess sawdust) is to blame for most sanding mistakes. Changing your sanding paper regularly and cleaning up sawdust as you go will help avoid these mistakes.
- Check for mistakes before changing to a higher grit. Shining a bright light at a low level reveals problematic defects that may not be visible in direct light. The only way to remove swirl marks and pigtails is to properly re-sand the area with the same grit that created the defect, which is why you should check for and eliminate them before changing to the next level of sanding paper.
Learn about the differences in a grinder and a sander for your next wood project.
Proper preparation is key to successfully sanding rough wood. Start with a low-grit sanding paper before moving on to medium and fine grits. Clean up sawdust and check for mistakes every time you change sandpaper.