The oilstones used for sharpening lathe tools do not differ from those used in sharpening joiners' tools. Both should cut freely and smoothly. If the tools are rubbed on a strop after whetting, the edge will be made smooth, and it will cut better.

Gouges are not easily rubbed on a strop, and, therefore, a very hard stone is used to remove the wire edge, and give the smoothness required for fine work. Such stones are usually shaped as shown in Fig. 289, and are called oilstone slips. They vary greatly in size. For sharpening ordinary turning tools, use a slip about 3 inches long by 1 1/2 inches wide.

The grade known as hard Arkansas is excellent for school use. These stones are very brittle, and should be used with care. Use oil on them the same as on the India oilstone, used in the wood shop.