Historic Finishing Workshop – Big Board Exercise Second Inning
It is worth reiterating the purposes of the Big Board exercise, which in many ways is the foundation for the whole workshop curriculum. When I present a 2-foot by 4-foot piece of unremarkable luan or birch plywood to the students and tell them they will be finishing this entire board with a 1-inch watercolor brush, their quizzical expressions are met with my exhortation to hang in there as the outcome will be workshop-life-changing. Once this exercise is completed, actually it is an entire series of exercises embedded into a single plywood board, the student will have become fearless Finishing Ninjas. Everything else in the workshop is frosting on the cake.
I have come to refer to each finish application session as an “inning”, and the big board exercise for the workshop entailed three innings. First thing on Day 1 it was a light abrading with a pumice block followed by four or five consecutive brushed applications of the shellac varnish, then set aside for several hours. Inning 1 was my opportunity to preach about the selection of the correct brush and proper use of that brush. Even by the end of Inning 1 it was readily apparent that a near-perfect film could be built with that 1-inch watercolor brush, with no resulting overlap margins due to good brush technique.
Inning 2 commenced with a light sandpaper smoothing of the material deposited during Inning 1, followed by another four or five consecutive applications of the brushed spirit varnish. Again, this was set aside, this time until the following morning.
By this point we were well on the way to constructing an excellent foundation for the final elements of the exercise as almost a dozen layers of spirit varnish were flowed on skillfully.
When finishing things with shellac, my first few coats of shellac get applied using chip brushes from the hardware store. I’ve had people tell me I need to use a better brush, but especially for those first couple coats of a 1.25# cut (2 oz of flakes in a 14 oz salsa jar), I haven’t found anything better than a chip brush, as long as I give the old one time to soak in the shellac long enough to soften the previous shellac in it.
For a pad, I agree with the cheesecloth core, but I’ve been using pieces of old T-shirt (nearly lint-free after years of washings) to wrap it. I should acquire some linen cloths to try on the pads, but I’m fairly happy with my results with t-shirt, and I have lots of those on hand.