Sharpening systems are a matter of personal preference and budget. There is no "right" way to sharpen your tools (but there are plenty of "wrong" ways). As long as your system is capable of quickly putting a fine edge on your tool it will work. Many turners use a standard bench grinder with aluminum oxide wheels (or better). Others prefer more esoteric systems such as the Jet or Tormek. Such high-end systems work very well if you have the budget or already own one. If this is the case you may want to look into special attachments for turning tools.
Bench grinders are one of the more common methods of sharpening, and the least expensive (other than sandpaper or hand stones - both of which can work but are extremely slow). Grinders generally come in three flavors: high-speed (3450 RPMs), low-speed (1725 RPMs), and variable-speed. Regardless of what anyone tells you, it doesn't matter what speed grinder you use for sharpening HSS tools. Any of the above will work.
Another grinder choice you'll be faced with is wheel size. 8" grinders are often touted as putting less of a concave on the tool bevel than a 6" grinder. Again, it doesn't really matter. The wood is not going to know the difference. The best argument for 8" wheels is that they are available in 1" wide offering you a bit more sharpening surface to work with. 6" wheels are generally 3/4" wide. Again, the difference is a matter of convenience and personal preference. Either will work.
As mentioned above, aluminum oxide wheels (or better) are well suited for sharpening HSS steel. Wheel color is not important. Wheels between 80 to 120 grit are generally considered good for sharpening. 60 grit wheels (or lower) are best for reshaping but could also be used for sharpening with a light enough touch.
One of the most popular grinder set ups out there is the Woodcraft 8" slow-speed grinder. It sells for around $100 and comes with two AO wheels making it a great bang-for-the-buck.
Last edited by Neal Addy; 01-03-2010 at 11:55 PM.