Hand sanding works best: Walnut, although easy to work with, can be difficult to finish. To help bring out the amazing grain patterns in walnut, hand sanding works best. Simply use finer grits of sandpaper as you go along to get a smooth finish that showcases the beautiful grain patterns walnut is known for.
You shouldn't need to go any finer than 180 or 220 grit for this process. Using a rag or shop towel, coat your work piece with a liberal amount of the Tung Oil Varnish. Be sure to get the edges and end grain. While the oil is wet, sand it with 220-grit wet/dry sand paper.
The best finish for walnut is a clear one. Several coats of Danish oil provide clarity. For protection, add a compatible clear topcoat.
General Finishes EF Sanding Sealer is a high quality acrylic waterborne sanding sealer that builds fast and makes sanding smooth and easy. For wood with large, open grain, such as walnut or mahogany, sanding sealer is especially handy as a final fill after most of the grain has been evened out with grain filler.
All walnut pieces need a good regular dusting. It's best to avoid commercial cleaners. These can leave residue on lacquered wood or damage oil and wax finishes. Oil finished furniture does best with the application of natural linseed oil once a year.
Unlike cherry, maple, and oak (which all darken in color as they age), walnut wood will actually lighten slightly over time.
Walnut wood can change color depending on the way it's dried or its age. The heartwood usually is a dark brown color and the sapwood is a light yellow color. When the wood is left out in the elements, such as the sun, the lighter wood will turn darker and the darker wood will turn lighter.
The kernel of a young, only torn walnut has a light color, after lying for several days, the kernel it darkens a little. This is a natural and normal process. After drying, the kernel takes on its permanent color.
Walnut is a tough hardwood of medium density, with moderate bending and crushing strengths, and low stiffness. It has a good steam-bending classification.
As you might expect, veneered pieces are very delicate and require careful sanding to avoid irreversible damage. If you sand veneer too much, you may render it unusable.
As long as it has been seasoned for over a year, walnut wood is moderately easy to split in comparison to other types of firewood. However, there is an exception. If walnut trees are grown along a sprawling landscape, then the inner bark could become knotty and forked.
Woods such as oak, mahogany and walnut are characterized as having “open grain” because the wood pores are large. In contrast, “closed grain” woods like hard maple, cherry, poplar and beech have smaller pores. You don't have to fill the pores of any wood before applying a finish.
Species such as maple and walnut dry at an intermediate rate, ie a 1” walnut board air dried in the south in the summer time will dry in about 120 days, and species such as oak, mesquite, and hickory dry very slowly (ie 1” per year).
Is wood conditioner necessary? Wood conditioner is not necessary. You can stain perfectly fine without it. However, as you will see with my test pieces below, using a pre stain conditioner results in smoother finishes, especially when using dark wood stain colors on light, soft woods.
Freshly sawn Walnut is a greenish-brown color heartwood with nearly white sapwood. This is a stark contrast for many who desire the appearance of all heartwood. The removal of the sapwood can be costly as the perimeter of the log contains the clearer, and hence more valuable lumber.
Sometimes during the finishing process we use water to 'pop' the grain before final sanding to help achieve a smoother finished surface. It also gives you a sneak peak into what the piece will look like when the finish is applied.
Paraffin wax, available in the canning section of your grocery store, is a great sealer for end grain cutting boards. While boiled linseed oil will cure to a solid, it would take many applications and a lot of drying time to seal the end grain enough to keep food juices from seeping in.
New walnut has a consistent dark-brown color but as it gets older, two changes occur. 1: Unlike maple and cherry, it gets lighter. 2: A rich honey color starts to come through the grain. You can see the difference between a new table (left) and a four-year-old table (right).