I use a V tool carving tool to first cut the grooves. Then I use gouges or my Dremel to round over the "beads". The I use a wire wheel in the drill press or lathe to cut the texture. You have to find the right wire wheel. I usually buy the cheap ones from Harbour freight in a couple of varieties. ONe of them will usually be the right stiffness for your particular wood. Softer wheels produce a finer texture. When I have that done I use a V shaped riffler file to cut the very bottom of the grooves for a cleaner look. Then I follow this with a soft brass brush. I usually use Krylon Fixatif as my spray finish for this texture. I learned this from John Jordan.