Can damar varnish be used as a wood finish?

Answer 1

Damar varnish is an excellent wood finish. I have used it on two kitchen table tops.

When dry, damar varnish is hard as nails. It dries very clear. Many layers of damar varnish can be used to coat a surface. There are two primary benefits: Irregularities will become filled (leveled, when performed carefully); and, each additional layer provides additional protection to the underlying surface. When complete, the damar varnish provides a waterproof, stain resistant, scratch resistant, glossy surface.

Specifically, I have used damar varnish as a finish to table tops that have been painted with oil paint, by a local artist. I started with damar concentrate. For each additional layer I added gum turpentine to the solution. In this way the varnish contained a gradually increasing the amount of fat for each additional layer. Between layers, I hand sanded with 220 grit sand paper and sanding block.

DAMAR CONCENTRATE

A solution of one part damar crystals (by volume) to one part gum turpentine yields "damar concentrate". Use ONLY pure gum spirits of turpentine. Example: 1 lb damar crystals + 1 qt gum turpentine yields 1 qt damar concentrate.

Expect the damar crystals to contain impurities - this is common. Expect to wait several days for the damar crystals to dissolve in the pure spirits of gum turpentine. Slowly stir the solution once in the morning and once in the evening until completely dissolved. This part requires more waiting than actual stirring. I recommend mixing in a wide mouth mason jar and not filling to the top (leave space for stirring).

When completely dissolved, the solution will be thicker at the bottom than the top and most of the impurities will be towards the bottom. This is okay. Carefully pour the solution through a layer (or more) of cheese cloth into another mason jar to remove impurities.

The result is ~ 1 qt of damar concentrate. Damar concentrate has the consistency of honey. If the solution is not that thick, the solution can be set aside to evaporate (in a well ventilated area) until enough of the turpentine evaporates to get the honey-like thickness.

USE AS FINISH

Damar concentrate may be used as the first layer of varnish. This is what I used on the table tops. I started by leveling the table top. Specifically before adding any varnish I made the table surface approximately level - so that the drying varnish would result in a flat and level surface. I used the first two thick varnish layers to fill in the differences between layers of oil paint (note: the method used by the artist resulted in differences in height in the surface of the table top. The subsequent task of filling in the difference with damar concentrate is part of the design.)

I allowed this to dry. I cleaned off layers of dust that accumulated during the drying process. I used 220 grit sandpaper to remove defects, insects, and to add enough bite for the next layer of varnish. I mixed a solution of two-thirds damar concentrate to one-third gum turpentine for the next two layers. With oil painting, the rule is "fat over lean" - and so it is with this varnish.

Briefly, the reasoning behind "fat over lean" is to account for the way damar varnish "dries". Damar varnish does not dry by evaporation. It dries by oxidation. The topmost layers of varnish must remain flexible while the lower layers (layers closer to the wood) are drying. The varnish, though it will feel dry at the surface, will actually be drying from the inside out. Interesting. For more detail about oxidization, ask someone who has been in through the first chemistry series at university.

RESOLUTION

I have struggled to find concise, clear, expert guidance from a craftsman on "using damar varnish as a wood working finish". I offer the above as a recommendation only. I encourage the reader to experiment and respond. I would like to understand more about damar varnish in woodworking.