The scraper steel is then passed rapidly to and fro on the flat side of the scraper, Fig.

157.
After that the edge should be turned as before.
[Illustration: Fig.153.Sharpening a Cabinet-Scraper: 1st Step, Drawfiling.] _Sandpaper._ The "sand" is crushed quartz and is very hard and sharp.
Other materials on paper or cloth are also used, as carborundum, emery, and so on.

Sandpaper comes in various grades of coarseness from No.

00 (the finest) to No.

3, indicated on the back of each sheet.