It’s not necessary to sand above 180 or 220 grit when applying an oil or oil/varnish blend finish. You can achieve the same smooth feeling results by sanding each coat after the first while that coat is still wet on the wood. You are wiping off all the excess anyway, so sanding dust isn’t a problem.
Here are the steps:
- Sand the wood to 180 or 220 grit, sanding in the direction of the grain.
- Apply a wet coat of boiled linseed oil, 100% tung oil, your own mixture or oil and varnish or one of a number of commercial brands of oil/varnish blend (often called “Danish” oil).
- Keep the finish wet on the surface for at least 5 minutes, adding more finish to areas that become dull.
- Wipe off all the excess finish. (Be sure to hang your rags individually to dry so you don’t risk spontaneous combustion.)
- Let the finish on the wood dry overnight (three days for tung oil) in a warm room.
- Apply a second wet coat and sand with the grain using 400- or 600-grit wet/dry (black) sandpaper while the surface is still wet. You don’t need to use a sanding block to back your sandpaper.
- Wipe off the excess and let dry overnight (three days for tung oil) in a warm room.
- Apply a third coat using the same wet-sanding technique if you want. You’ll usually improve the results a little with a third coat.
Run your hand over the surface. It should be silky smooth with a beautiful soft, satin sheen—and with much less work and better results than if you sanded the wood through all the sanding grits up to 400 or 600 grit.
