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| Ask Dale is a regular column featured in Woodturning Design. Listed below are the questions and Dale's answers from Issue 18. | |
| I am a relatively new turner and am having trouble using the scrapers without getting some tearout, particularly on the end grain in bowls. Could you explain the proper technique to prevent this from happening? | |
| I don’t believe you can eliminate tearout on the end grain in bowls. However, the problem can be reduced to an acceptable surface by following these recommended suggestions. Tearout can be extensive or minimal depending upon a number of factors. First, the extent of the problem may depend on the material being turned. Soft hardwoods such as aspen are difficult to scrape without tearout. Hard, dense woods such as sugar maple will scrape with little tearout. Highly figured areas which contain multiple grain directions are difficult to scrape clean, so some of the problem with tearout will depend in part on the selection of material. Second, treat your scraper as a finishing tool and use it to remove fine, tissue-like shavings. Take light cuts, because heavy shavings will increase tearout and make the problems more difficult. To accomplish this, the tool should be freshly sharpened, with a light burr on the cutting edge. When you pick up a scraper, run your thumb across the top of the cutting edge. If it feels smooth, the scraper is dull and needs to be re-sharpened. Keep in mind that the scraper may need to be sharpened frequently because the burr edge is weak and quickly worn off. You cannot produce a smooth, quality surface with a dull scraper. Third, the scraper tool must be presented to the wood in “trailing mode,” which means that the tools should not be used with the bevel rubbing, but must be pointed slightly downward. The cutting area of the scraper should be at the center of the work, but the handle should be above center. Raising the handle makes the cutting action less aggressive and the tool less likely to “catch” or dig in. The trailing position will require the tool rest to be raised to support the tool at the correct angle. Fourth, once all shaping and surface blemishes have been removed, there may be slight “bruising” or very shallow tearout in an area or two of end grain. Some turners will lightly oil these sections, working the oil well into the area. Let it stand for a few minutes, then with a freshly sharpened scraper, take a very light cut or two, just skimming the area. This will usually remove the last visible signs of tearout. Another way to improve the quality of the interior end-grain surface of a bowl is with the shear scraping technique. Mastering this technique takes a lot of practice, but a tool called the Kelton Shear Scraper can be very useful for finishing bowls and other similar types of work where irregular grain pattern or tearout is a problem. This tool is easy to control and adjustable to the exact angle you need for various applications. The tool has a milled flat surface on the shank to automatically position the cutter at 55° for an optimum shearing cut. |
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| I know that Dale has answered several questions regarding lathe speeds for turning, but how about some insight into how fast the lathe should be going for putting on waxes and other finishes? How about the best speeds for sanding? I don’t have a digital readout on my Jet lathe; it just has six positions for the pulleys. The manual tells roughly the speed by the pulley location, but is it important to be exact? |
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| There has been a lot of discussion regarding speeds for sanding. Personally, I sand at the same speed at which I turn. It might be better to lower the lathe speed a bit, but it’s too much trouble to change speeds, especially on a step pulley lathe. However, lowering the lathe speed about 30% will probably allow for efficient sanding and reduce heat buildup between the abrasive and the work. I think it is more important to use new abrasive paper and discard dull or clogged papers. You will get better results “if you use abrasives like someone else is paying for it.” Using abrasives too long can cause problems such as surface checking, caused by friction built up from used abrasives. Also, a worn piece of 220 grit, for example, cannot and should not be used to replace 320 grit. Waxes and other finishes, such as friction polish, can be applied at the same speeds at which the work was turned. Answering the lathe speed question, my previous responses to lathe speeds have not indicated that speeds need to be exact. Other factors, such as the balance of the workpiece, soundness of stock, and length of the spindle, must be taken into consideration. If in question, always set the lathe speed on the lower side. You can always speed it up. |
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| I am a novice turner. Years ago, my wife bought me a Craftsman lathe for my birthday, and I spent some time reading and experimenting with it. But hard times forced me to work two jobs for nine years, pretty much killing any turning time. In the meantime, poor environmental conditions in my garage seriously damaged my lathe. Now I intend to get a new lathe and pick up where I left off. I am primarily interested in small spindle work. When I was attempting to teach myself, I had many notable adventures with my skew chisel, as you can imagine. Out of frustration, I finally put together something I saw in Holtzapfel’s Plain or Simple Turning, along with things I read in Frank Pain’s Practical Woodturner, and reground my skew chisel into a square chisel with a single 30° flat bevel on the underside. This tool I was able to use! So my question is, should I continue to develop skill with an out-of-fashion tool with which I am comfortable, or should I abandon it and force myself to learn to use a skew chisel? (Please don’t say I should use a skew chisel because everyone else does. That is not my nature!) |
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| The tool you have developed is probably only new to you. It has likely been used for years by other turners in other parts of the world and you were not aware of it. In North America, Britain, and Europe, the skew is a common and useful tool, as you well know. However, in France, a tool called a Bedan is the tool of choice for cutting beads, sizing tenons, and smoothing small diameter spindle work. In Utah, we have a production turner who is highly skilled and proficient in using the Bedan, and is, in my opinion, one of the best I have ever seen. Tom Sorensen grinds his own tools from a flat bar stock of high-speed steel. The tool is flat on the top and shaped to a round nose shape, then it is ground to a 30° angle on the underside. It will make most of the cuts usually made with a skew and some cuts which can be made with a gouge. The sheared surface made from this tool will require little or no sanding. The tool is commercially available as the Spindlemaster and made by Robert Sorby of England. There are usually many ways to solve a problem, and you have developed a way that works for you. So go ahead and use your method. Most turners would agree, “If it’s not broke, you don’t need to fix it.” Good Luck! | |
| I am a new turner, and have been turning for about two years. I’ve been turning mostly bowls along with some miniatures on my mini lathe. Now I’ve become interested in turning some plates and platters. I own quite a selection of books by many authors. Unfortunately, I have not been able to find any literature on this subject. It appears that the topic just simply isn’t covered in any detail. I am interested in learning about holding fixtures, specifically methods of holding the front and reverse sides of the plate/platters. Could you point me in the right direction and possibly provide some helpful hints on the subject? | |
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Platters are a very useful woodturning project. They are typically turned from wood 1-1/2" to 2" thick and usually 12" to 16" in diameter. Typical uses are for serving crackers, cookies, etc. The following instructions are for use with a screw center faceplate, but a regular faceplate screwed to the top of the platter would work just as well. Step 1: (a) Drill a 1/4" hole 3/4" deep for a platter 1-3/4" to 2" thick. (b) Install the screw center faceplate onto the lathe, and screw the platter onto the screw. (c) For a 12" to 14" platter, set the lathe speed at around 500 RPM. Step 2: (a) True up the edge of the platter. (b) Face off the bottom. (c) Lay out the dovetail recess which will receive the chuck jaws in the expansion mode. The recess is 3-1/2" to 4" in diameter and 1/4" deep. (d) Remove the waste wood from the dovetail recess with a small gouge. (e) Clean up the corners and cut a 5° dovetail angle. Step 3: (a) Turn a foot ring around the recess area. The diameter of the foot ring should be about half the diameter of the platter. (b) Turn the platter to rough shape. (c) True up both sides of the outside rim. (d) Complete the outside shape. (e) Design the rim so it feels comfortable in your hand. (f) Sand and finish the outside of the platter, including the recess. Step 4: (a) Remove the platter from the screw center faceplate. (b) Install the expanding chuck on the lathe. (c) Fit the platter to the expanding chuck. Tighten securely. (d) Move the tailstock with the revolving center into the support position. Step 5: (a) Turn the inside of the platter with a 1/2" bowl gouge. (b) Turn a gentle pleasing curve from the rim to the bottom. (c) Measure carefully for depth. Leave 1/4" or more wood above the dovetail recess. Step 6: (a) Sand and finish the inside of the platter. Sanding: I prefer the Velcro sanding system. The 2" pads work well on the outside of the platter, due to tighter curves. The 3" pads work best on the inside, making it easier to keep large areas flat and smooth. I suggest a sanding sequence of 80, 100, 150, 220, and 320 grits. Finishing: I prefer finishing the platter with a full wet coat of lacquer sanding sealer, brushed on. Let the full wet coat stay on the wood for a minute or two, then wipe dry with a cloth, rag, or paper towels (I prefer Viva brand). When the wet lacquer has been removed, turn on the lathe and spin the platter against a clean cloth, rag, or paper towel until all the lacquer has been removed from the surface and the surface feels dry. The platter is now ready for a coat of Danish oil. I prefer Waterlox, which seems to give a satin sheen finish with only two or three coats. Apply the Waterlox, let it set for three to five minutes, then wipe dry. Let the platter dry for 24 hours before applying another coat, repeating the procedure. |
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Reproduction of the contents of this website or magazine (including images) in any way whatsoever without written permission of the Publisher is strictly prohibited.
ANY unauthorized use of the materials contained within WILL be prosecuted to the fullest extent of the law.
Woodturning Design Magazine is published by All American Crafts, Inc. View our other magazines.