How to Finish Rough Cut Lumber
- 1). Sand the lumber with 100-grit sandpaper to remove dirt and surface imperfections. Attach it to a power sander to treat the majority of the wood, and use a sanding sponge to reach crevices and tight spots by hand.
- 2). Wipe the sanded surface with a tack cloth to clean off the sawdust. Otherwise, small particles of the lumber could become trapped during finishing.
- 3). Stain the lumber to enhance its color and appearance. Follow the manufacturer's instructions to determine whether you should brush, wipe or spray on the coat. Wait the recommended period for it to cure.
- 4). Wipe a light coat of sanding sealer onto the lumber using a painter's rag. Clean off the excess product before it dries, then allow the remainder to air dry.
- 5). Sand the lumber lightly with 280-grit sandpaper to ensure that the final finish adheres properly. Wipe the surface with a tack cloth once again to prepare a clean foundation.
- 6). Brush or wipe the lumber with a polyurethane wood varnish. This sealant provides the lumber with a protective coat against drying, cracking and general wear. Allow this first coat to cure overnight.
- 7). Sand the lumber with 280-grit sandpaper before a second application of the varnish. After the second coat, apply one to two more to provide the most long-lasting finish.
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