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Resumen del manual
Once a cylindrical form has been obtained, you can change the turning speed to the second or third speed setting. NOTE: Continue to move the tool rest inward toward the work piece to keep the safe distance between the two. POSITION OF HANDS While turning, the hand that holds the tool handle should be in a natural position. This hand provides the leverage for the tool by either moving in toward the workpiece or moving out. The position of the tool rest hand is more a matter of individual preference, rather than a “set” or “proper” position. However, a palm-up grip (Fig. 36) is generally considered best. In this position, the first finger acts as a guide, sliding along the tool rest as the cut is made. The alternate position is a palm-down grip (Fig. 37). In this position, the heel of the hand or the little finger serves as a guide. The palm-down position is solid and positive – excellent for roughing or heavy cutting. Most beginners start with the palm-down grip, switching later to the palm-up position for better manipulation of the chisel. Fig. 36 Fig. 32 Fig. 33 Fig. 34 Fig. 35 Fig. 37 13 SMOOTHING A CYLINDER To smooth a cylinder, use a large skew chisel. This requires practice, but experience with this tool is very important. Place the cutting point near the center of chisel and high on the work (Fig. 38). Sometimes, in striving for a certain position in relation to the work, the beginner will often overlook this all-important point. Raising the handle will increase the depth of cut while lowering the handle, of course, does the opposite. As with the gouge, you can advance the skew in either direction. The center of the skew toward the heel does the actual cutting. The back portion of the grind or bevel supports the tool, while the handle-hand controls the depth of cut by rocking the chisel on this pivot point. Because of this, keep the skew bevel perfectly flat. Fig. 38 Fig. 39 Fig. 40 Fig. 41 Fig. 42 USING THE PARTING TOOL The parting tool is perhaps the easiest turning chisel to handle. Simply push this scraping tool into the work (Fig. 39). You can achieve a somewhat better cutting action if the handle is held low. This tool is, in many cases, held with one hand while the other hand holds the calipers in the cutting groove. When parting tool cuts are deep, make a clearance cut alongside the first cut (Fig. 40) to prevent burning the tool point. SQUARING AN END You can use the parting tool to quickly square an end. Since the parting tool is a rough cutter, the cut can then be smoothed by the use of the skew. However, you can do the whole operation with the skew. First, make a nicking cut with the toe of the skew (Fig. 41). A deep cut here could burn the chisel, so make a clearance cut by inclining the skew away from the first cut and pushing the tool into the work. This procedure of side cut and clearance cut is continued as often as needed. NOTE: While the skew can be pushed into the wood in any direction, the cutting edge itself must be inclined a little away from this plane. If the full cutting edge of skew bears against the cut surface, the tool will have a tendency to run. See Fig. 42 for the proper way to make the cut. Push the chisel straight into the work, and incline the cutting edge away from the cut surface. Use only the extreme end of the toe for this cut. This important principle in skew handling will be used repeatedly in making shoulders, beads and vee cuts. 14 CUTTING A SHOULDER Use the parting tool first to reduce the wood to within 1/16” of the required shoulder and diameter (Fig. 43). Clean the waste stock out with the gouge (Fig. 45A), then use the skew for the actual cutting of the shoulder (Figs. 45A and 45B), which is a duplication of squaring an end. The skew then makes the horizontal cut, but in a different manner from plain cylinder work. If the shoulder is long, use the ordinary skew position for the outer portion of the cut. Move the chisel in at the angle shown in Fig. 45B. In this position, raise the handle of the chisel slightly to allow it to cut while the tool moves along the rest. Use a very light cut to produce smooth work. The heel of the skew can be used for making the entire cut, if desired, but the cut, whether in this position or any other position, should not be picked up directly at the end of the stock. Horizontal cuts started directly from the end of the work will have a tendency to bite into the wood, often ruining the entire piece. Always run off the end and not into it. Where a very short shoulder makes this impossible, use the skew in a flat scraping position. If the cutting technique is used, engage only with the heel of skew in a very light cut. Fig. 43 Fig. 44 Fig. 45A Fig. 45B Fig. 49 Fig. 50 Fig. 47 Fig. 46 Fig. 48 CUTTING SMALL BEADS Beads can be scraped or cut. Using the spear chisel is the easiest method of scraping, and works to best advantage on beads separated by parting tool cuts (Fig. 46). Scraping is slower than cutting and is not as clean, ...