Woodturning is one of the most basic of crafts and the requirements are simple; a wood lathe to hold the work and make it spin, wood to shape and tools to cut the wood. This is woodworking at its most basic. In order to also make it among the most enjoyable of woodworking crafts is that most basic of wood cutting needs, sharp tools. There are a few things to keep in mind when sharpening wood turning tools.
First is the edge that is sought after. Many wood workers seek to sharpen a knife, chisel or plane blade to a razor edge for a clean cut and lovely shaving. However the wood for a typical woodworker stays still while the blade cuts. At the wood lathe the opposite occurs, wood spins and the tool is guided to the cut. The spinning wood, often with bark, knots and perhaps included grit rapidly ruins a razor edge. So the edge sought is one that works well but is not so sharp as to disappear.
Second is the equipment needed. Woodworkers often get a beautiful edge with various stones while woodturners are more at home with a good tool grinder. Most of the time the tool will be sharpened at the grinder and presented to the wood. A good wheel made of aluminum oxide with a grit of 80 to 100 will give a serviceable edge with a good surface left on the wood.
Third is the skill needed to sharpen that array of woodturning tools. Many woodworkers will need to sharpen straight edges with the possible foray into sharpening saws and wood carving gouges. Woodturners have tools with blades straight, curved, round, and fluted. Many have angles of sharpening that vary along the curved edge. While being able to sharpen freehand is a great asset, sharpening guides are wonderful assets to both the professional and the amateur.
Fourth is the frequency of sharpening. While the person who has learnt how to sharpen a knife well will find themselves infrequently going to the sharpening bench, a woodturner may find themselves at the tool grinding machine every couple of minutes. This makes a difference as to how a person sets up the shop to prevent too many footsteps between the wood lathe and the grinder.
Fifth comes the selection of tools. Principally they are made of three materials for the blades, high carbon steel, high speed steel and specialty steels. For all intents and purposes, most turners use the high speed steels. They will hold an edge longer than high carbon and are significantly cheaper than the specialties. A grinder with that aluminum oxide wheel will do a good job on them and will be adequate for each of the others, especially when using a sharpening jig.
Sixth is the consideration of what cuts are required by the tool. This may mean that some otherwise identical tools need to be sharpened with different configurations. Turning wood bowls is an excellent example. Some cuts are best performed with a bowl gouge sharpened straight across at a forty five degree angle. Others need a similar bowl gouge but shaped to have long wings and an angle varying from about seventy degrees at the tip to forty five along the edges. Again, a sharpening jig simplifies the sharpening process.
Seventh and perhaps most important is learning to relax while sharpening the various tools. If a poor edge or the wrong angle is obtained, it is a simple matter to return to the tool grinder and fix it. Tension is more likely to ruin an edge than is poor technique. Besides, woodturning is meant to be fun. Relaxing and enjoying such a large part of the process only adds to the amusement. Once again, consider making or buying a sharpening jig to add to the joy of woodturning.
Sharpening woodturning tools is a skill accessible to everyone who wishes to turn wood or work with a wood lathe. There are a few things to keep straight but as in all things with wood turning, practise may not make perfect but it goes a long way to getting great results.
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