Musings

Finishing Workshop @ CW – Grain Filling 2

“Cold wax” grain filling with a rush polisher was integral to the finishing practices of the ancients.  It was primarily used to finish solid wood cabinetry as opposed to the hot wax method, which was generally restricted to fancier work like marquetry.

The process is so simple that there is almost no explaining to do.  The precursor step is to plane, scrape, and in some rare instances scour the wood with abrasives like sharkskin, glass paper, or horsetail rush.  Then,  the wood surface is scrubbed with  a block of beeswax until there is a generous, but not continuous, deposit.

Taking the fiber polisher in-hand the surface is rubbed with as much pressure and vigor for as long as you can manage, first working at a slight angle to the grain, then its opposite angle, then finally with the grain.  The friction developed at the point of contact between the tip of the polisher and the wood generates enough heat to turn the wax buttery and presses it down into the grain, filling it.

In some instances, as I had them do in this exercise, the surface is sprinkled with a colorant, usually powdered pigment or resin that has been ground into a fine flour.  In this case I had them use some raw umber pigment to accentuate the technique (in the real world the colorant would be selected to best fit the coloration of the wood).

When finished any excess wax would be scraped off then the surface buffed with linen and wool rags until there is a uniform gloss.

For most plain solid wood furniture and cabinetry, this actually sufficed as the finished surface and nothing more would be done.  You can see the resulting surface at the upper left corner of this sample board.