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Woodturning (rec.crafts.woodturning) To discuss tools, techniques, styles, materials, shows and competitions, education and educational materials related to woodturning. All skill levels are welcome, from art turners to production turners, beginners to masters. |
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Over on Olympus there is a thread on roughing gouges, their design and use.
It is a thread which has come up here amongst the Hoi Polloi as well, and the same old positions are being restated. Might as well restate mine. A roughing gouge is designed to remove a large shaving in a single pass, and in spite of a long history of service to turners, its detractors seem to feel that it is poorly designed for the task. I am not one of them, as I regularly use and teach the use of the "Big Kahuna" 1 1/4 U-shaped Sorby and the 1 3/8 shallow Sorby to 6 - 12th grade youngsters. The problem as stated is the weakness of the tang, which should be no problem at all if the gouge is properly applied to the task. First, the gouge is not designed for great reach over the toolrest. That's what bowl gouges are for. I'm sure I don't need to do the "Four Simple Machines" demonstration which I give in 6th grade Physical Science labs to remind turners that we are dealing with a fulcrum and lever, and the mechanical advantage is heavily in favor of the operator when the overhang is less than an inch. Keep it that way or chose another tool. Second, bringing the wood to the gouge rather than the gouge to the wood, as in scraping, relieves much of the force on the gouge, transferring it along the tool instead. Keep the toolrest low, the handle of the tool lower, and don't push into the wood, but allow the wood to contact it, peeling back what you don't want. You can use the gouge anywhere along its edge, either perpendicular to the piece or askew, bringing it in tangent to the turning, then moving it in the downhill direction, allowing the wood to peel as you move laterally, where the vector force is now along the tool. The sides of the "U" can be used as an extremely stable skew on spindle turnings or on flat or convex surfaces of faceplate (bowl) work, as long as you keep the corner in trail and out of contact with the surface. The curvature of the gouge is actually a help in taking larger bites, as it takes a progressively deeper shaving when the curve is at the first point of contact with the wood. Third, you can use the "U" gouge as a _very_ wide parting tool or Bedan when cutting tenons by laying it on its side on the rest and allowing the bevel to ride the surface. This works even when the piece still has corners, but it demands a gentle hand to present slowly initially, waiting until the bevel rides tangent to the new surface to begin removing heavier shavings. Now for that big shallow fingernail 1 3/8 gouge, which has most of the benefits available to the "U" without the danger of catching a corner. It can even be used inside shallow turnings with little danger as long as, of course, the overhang is minimal, the handle is low, so as to transfer the force longitudinally, and there's space to swing the handle laterally as you approach the bottom. Deeper work, of course, favors the bowl gouge, with its shorter bevel at the bottom. If there's a proper mindset to turning, it has to be what old Frank Pain said - cut the wood as it wants to be cut. When you do that, there's very little force required on the handle, therefore the tang. And there are _shavings_ coming off the tool, not dust. |