This is usually called "Sanding". I prefer to call it "Surface Preparation" because the finish can be no better than the surface of the wood under it. For more information on sanding turned wood, please read, My 5 Rules For Sanding in my "Finishing Secrets" articles.
Start sanding at whatever grit is necessary to remove ALL of the torn grain from the tool. Do any reshaping of the watch with the coarse grit. I sand at about 800 RPM to control the heat and dust.
From here on, all I am doing with the finer grits is refining the scratch pattern of the sandpaper.
Work up through the grits, removing all of the scratches from the previous grit before going on to the next. Keep the sandpaper moving to reduce scratches.
Stop sanding at 280-grit. Stop the lathe and look for blemishes and torn grain. Fill any cracks or voids in the wood, and then go back to whatever grit is necessary to level the repair. Repeat the travel up through the sanding grits.
Don't be too concerned with a few sanding scratches. We will remove all of them during the next several steps. And, don't wipe away the dust. It will be used as a grain filler in the next step.
I apply a coating of CA to every watch whether it needs it or not. It acts a "hardener" for soft woods, and as a grain filler for the harder ones. "Thick" CA works the best because of its slow cure. "Medium" is OK if we work faster.
Apply it with any synthetic material. I make little applicators from synthetic dressmakers batting stuck to a short piece of 3/4" wide masking tape with another piece of tape wrapped around this one to make a handle that keeps my fingers from sticking to anything. Do not use a cloth or paper towel to apply CA glue because the cellulose in the material acts as a catalyst.
While the CA is still wet, wipe it with a piece of soft paper towel. The cellulose in the towel will act as a accelerator and the glue should cure to a smooth surface.
Now we go back to sanding again.
Start with 220 and 280 grits used dry, and remove all of the CA from the surface. The CA is used as a wood filler and hardener, and not as a finish. We want the glue IN the wood, not ON it.
Put 4 or 5 drops of the CA glue across the applicator, and then apply a uniform wet coat to the watch. Use a slow lathe speed to keep the glue from being slung into your face.
Now we wet sand the watch, starting with 320 grit, followed by 400 that is also used wet. I use the Watco Liquid Finishing Wax as a lubricant, but any paste wax will do as well. Use a lathe speed of about 800 RPM or whatever will not sling the wax from the surface.
Wipe all of the gunk from the watch. Then continue sanding with finer grits. I follow with 600, 1000, 1500, and 2000 grits that are used "dry". There is no need for lubrication with these finer grits because there is sufficient residual wax on the wood.
Then speed the lathe up to at least 1600 RPM, and burnish the surface with a piece of brown grocery-bag paper. This is the equivalent of a 2500-grit, and will leave a polished surface on the wood.
