![\"movingui](\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2014\/12\/movingui-block-300.png\")
<\/a>\u00a0 ![\"granadillo](\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2014\/12\/granadillo-block-300.png\")
<\/a><\/p>\nFour rectangular knob blanks cut from each block (+1)<\/p>\n \u00a02.\u00a0\u00a0 \u00a0The center of a horizontal surface is marked on what will be the bottom of the knob.\u00a0 Done imperfectly, this will cause wastage and a smaller knob.\u00a0 From that center point, a circle is drawn in pencil to the nearest edge of the side, for later use in roughing out the knob.<\/p>\n 3.\u00a0\u00a0 \u00a0Because these knobs are turned on a wood lathe using the threaded shaft of a pen-making adapter (Woodcraft #145998), a \u00bc-28 hole is drilled and threaded into the center of the bottom of the starting block.<\/p>\n 4.\u00a0\u00a0 \u00a0A special bit adapted from a 9\/16 spade bit is used to hollow out the bottom so that it will pass the threaded shaft and mounting nut of the control.<\/p>\n 5.\u00a0\u00a0 \u00a0The starter block is turned up on its side, with the grain horizontal and drilled and threaded for a 5-40 set screw, to meet with the splined or smooth control shaft.<\/p>\n 6.\u00a0\u00a0 \u00a0A belt sander then takes the corners off the block, just outside of the previously inscribed circle in (2).<\/p>\n 17 roughed-out knobs with hollowed and threaded bottoms and threaded set screw holes<\/p>\n Detail of single roughed-out knob<\/p>\n Detail of set screw hole<\/p>\n Lathe left to right:<\/p>\n pen-making adapter, spacer, rough knob w\/carbide bit and holder, tailstock<\/p>\n 8.\u00a0\u00a0 \u00a0The live-center tailpiece is push up to the starter block.\u00a0 The lathe is started and the tailpiece point is pushed into the starter block until it meets significant resistance and spins.\u00a0 Unfortunately, this is necessary because the adapter does not sit perfectly in the lathe headstock socket and will otherwise loosen while the block is cut to cylindrical shape.\u00a0 This leaves a dimple in the top center of most of these knobs.<\/p>\n 9.\u00a0\u00a0 \u00a0The starter block is cut to a cylinder on the lathe.\u00a0 At any point in the cutting from this point onwards, the tool can always catch in the wood and gouge it, requiring a change in the size and design of the knob as the gouge is cut away.\u00a0 This is especially true with a horizontal grain knob, because as the tool cuts from the end grain to with the grain, it can break off a chip even if it doesn\u2019t catch and gouge.\u00a0 So few if any planned designs survive contact with the tools.\u00a0 The knob designs must always be flexible.<\/p>\n 10.\u00a0\u00a0 \u00a0The ends of the knob, top and bottom are squared off.<\/p>\n 11.\u00a0\u00a0 \u00a0The top of the knob is usually rounded over.\u00a0 This allows the thinned finish to flow off of it without pooling.<\/p>\n 12.\u00a0\u00a0 \u00a0Now the basic profile of the knob is cut, and rough diameter set, all subject to how the wood reacts to the tools.\u00a0 At this point knobs with horizontal grain usually develop white spots at or near the end grain sides.\u00a0 Apparently the tool cuts away softer wood, leaving whiskers of tougher fiber sticking up.\u00a0 Only filing or sanding will get rid of these spots.\u00a0 This extra work is the price of iridescence.\u00a0 If the wood has no iridescence, the grain might as well be vertical.<\/p>\n 13.\u00a0\u00a0 \u00a0Before or after the white spots are removed, the tailpiece is pulled away.\u00a0 Final sanding includes filing and sanding the top to remove any tool marks, white spots and ridges around the tailpiece dimple.<\/p>\n 14.\u00a0\u00a0 \u00a0Now the knob can be polished to a high gloss with decreasing grits of sand paper, including 0000 steel wool.<\/p>\n 15.\u00a0\u00a0 \u00a0Removing knob from the lathe adapter requires a sheet of rubber and channel lock pliers, because it has jammed tightly on the threads from the force of previous cutting.<\/p>\n 16.\u00a0\u00a0 \u00a0For finishing with polyurethane varnish, the polished knob is dropped into the thinned solution to soak a short while, then taken out, wiped off and left to air dry.\u00a0 About twice a day, the knob is recoated with the thinned polyurethane solution until it becomes glossy after drying.\u00a0 This can take up to a week.\u00a0 Usually the thinned solution flows smoothly over the knob and leaves only a thin coat with few defects.\u00a0 The knobs may be polished with an ultra-fine abrasive cloth in between coats to take out any dust or other particles that have settled on them, or to break down small finish bubbles that have dried without popping.<\/p>\n 17.\u00a0\u00a0 \u00a0The \u00bc-28 threads have been left in the mounting hole in case the finish fails and needs to be removed by sanding or to be repolished on the lathe.\u00a0 Once the finishing is done, they must be very carefully drilled out to \u00bc inch.<\/p>\n 18.\u00a0\u00a0 \u00a0At this point the set screw hole should be rethreaded to clear out the finish.<\/p>\n Done.\u00a0 We now have a one-of-a-kind wood guitar knob, with beautiful or spectacular or iridescent grain, depending on the wood.<\/p>\n","protected":false},"excerpt":{"rendered":" On a couple of YouTube videos, the makers chuck a round wood dowel into a metal or wood lathe (presumably with the grain along the length of the rod), cut a curved version of a top-hat knob, drill out a … Continue reading <\/a> <\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a>7.\u00a0\u00a0 \u00a0The block is screwed onto the pen-making adapter shaft, backed up by a special spacer.<\/p>\n<\/a><\/p>\n