Correction. At the end of the last paragraph I should have said, "one other advantage of the flat bevel systems over the Tormek system... David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Tuesday, October 19, 2010 9:06 PM To: pianotech at ptg.org Subject: [pianotech] Chisel Sharpening epilogue After our lengthy discussion I wandered into my favorite spend-whatever-extra-money-I-have-store, The Japan Woodworker, with my chisels in hand to try various sharpening systems that they had available. I won't bother you with everything but I tried various systems, hand and machine, including the Tormek T7, Lap Sharp and Work Sharp systems. The best system, I found, was the Lap Sharp system ($795) LS 200-2009. It can be used either wet or dry and features replaceable abrasive discs in a range of grits and has a honing guide that will hold all types of chisels and plane irons at precise angles which are easy to duplicate. The system is fast and easy to use but expensive. The Tormek T7 ($599) system also works well especially if you use gouges and things as it has some accessories that makes sharpening them easy and quick (also expensive). Using quality diamond or wet stones with a proper guide also does a good job but it is slower than the machines and by the time you purchase the various stones (some up to $90 each) and guides is not that much less expensive than a quality machine. The best machine for the money that I found (in fact I ended up buying one) is the Work Sharp WS 3000 ($199). The is a dry system using replaceable pressure sensitive adhesive disks of various grits that adhere to a thick, removable glass disk. The system comes with two glass disks and you adhere the abrasive disks to both sides creating a sequence of 4 (or more if you want to buy more disks) progressive grits that is more than adequate to get a very finely polished and sharp result. Very simple and quick to use and easy to duplicate honing angles. You do need to purchase a Wide Blade Sharpening system design for this machine to accommodate wider blades (especially plane irons) over 2 inches wide ($60). The replacement disks are not expensive and available in grits from 80 - 6000. You can also purchase a leather honing disk for fine polishing ($28). One comment, at least according to the folks here, is that if you use Japanese chisels (which I do), it's not recommended that you use hollow grind systems (like the Tormek). The reason is that the Japanese chisels are made of two types of metal laminated together--a high carbon steel (which is the cutting part) and a low carbon softer steel for the backing. The hollow grind systems tend to remove too much of the backing which can impact performance and longevity (though honestly I didn't quite get exactly how). Nevertheless, they advise to use a system that creates a flat bevel. All the machines mentioned above will create a microbevel, btw, but only the Lap Sharp and the Work Sharp systems create a flat bevel as opposed to a hollow grind that comes from sharpening on a turning wheel as in the Tormek system. One other advantage of flat bevel systems is that as the Tormek wheel wears of course the diameter changes and thus the "hollowness" of the grind also changes and becomes more acute over time. A flat bevel system doesn't have that problem FWIW. That's my report. David Love www.davidlovepianos.com
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