Derek’s comments on the April Meeting
The Enchanted Woodturners had our first meeting at Santa Fe High School last night, and it was a great success. The woodworking shop is large and provides a good space for presentations. They have lathes and other equipment in place, which lessens setup time. Thanks to Dana Richards and SFHS for hosting us!
John Ellis presented an excellent demonstration on turning platters. He showed us half a dozen or more exquisite platters in varying styles, that he has turned over the years, and commented about the salient features in making them. He then took us through the process of turning a platter, starting with a bandsawn disk. John showed us how he attaches the workpiece, via double-stick tape, to another disk, made from MDF, to begin the shaping process on the lathe. He then trued the face, the rim, and cut the mortise/recess for remounting the workpiece in a scroll chuck in expansion mode.
Part of John’s focus was on the use of high vanadium content scrapers to produce a finish that requires very little sanding. John demonstrated several scrapers containing the V10 steel alloy, made by Doug Thompson. The scrapers had profiles similar to curved skews, with double-sided bevels, and roughly a 45 degree included sharpness angle. John showed how he creates a burr at the grinding wheel, turning the tool into a very fine negative-rake scraper. With a light touch, the finish quality is superb. John pointed out that the burr lasts a very short time, but once the grinder is properly set, the burr can be renewed in seconds. The burr makes this a temporarily single-sided tool; it can be reground on the opposite side, in order to reverse the burr, and allow the tool’s curve to match other parts of the desired profile. John said that while this technique can be used on other steel alloys, the burr on the high vanadium tools lasts much longer.
John took us through all the steps in making a platter, up to the moment when he would have begun finish sanding. For me, it was a very well-organized and clear presentation, filled with valuable information, and presented with great wit. Thanks, John.
The show and tell was less well populated than last month, but included intriguing examples of “the good and the bad”, as our president had requested, often on the same piece. Thanks to everyone who showed and explained their interesting works. Eric showed a beautiful large pine bowl, with striking blue stain coloring, which led to a discussion of where this color comes from. I’ve done some research today, and I’d like to pass along what I learned. Blue stain is caused by a fungus, listed in Wikipedia as Grosmannia clavigera, although other sites list other fungi names. It affects many types of pine and related trees, especially lodgepole and ponderosa, in this area. The fungus is carried by a beetle, but it can infect cut wood as it is drying, independent of the beetle. Several Virginia sawyers said that it is an issue in all pine cut during the summer months, in their area. Unlike some wood fungi, blue stain doesn’t decrease the strength of the wood. Several sites said that their are no specific health risks associated with blue stain fungus. However, one site said that individual people may be, or become, allergic to the spores of this fungus. The fungus becomes inactive below 19% moisture content, but the spores will remain in the wood. If the wood is sealed, it is unlikely that anyone using the turning would face significant spore exposure. Some people try to promote the growth of blue stain by storing damp wood in piles with some blue stained pieces, for a few months. All this is Internet research, so keep the quality and reliability of that source in mind.
The club voted to continue meeting at SFHS indefinitely. We also approved a letterhead design, incorporating our logo and that of AAW. Kathy Knorr created the design.
Next month, Taz Bramlette will present his hollowing system. He has been developing his ideas for more than a year, and has patented some of his improvements and innovations. I look forward to seeing his state of the art tool. I also hope to see additional works from all members, for the show and tell.
For the program committee,
Derek
SFTurners.org 