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| Usual method of thinning the point of a drill when the web has become too thick because of repeated re-pointing. | Undercut Thinned Point - Another common method of web thinning. If properly done, this type of thinning will produce a fine curled chip. |
| Diameter of Drill, Inches | 1/8 | 1/4 | 1/2 | 1 | Over 1 |
| Web-Thickness Expressed as a Percentage of Drill Diameter Variable | 20 | 17 | 14 | 12 | 11 |
