FILENAMES: Drill1.jpg Drill2.jpg DESCRIPTION: These are pictures of drill bits with special sheet metal points. Posted by Jim Rozen . Jim provided the following description: ================================================================= Here are two snapshots from Jim Rozen showing a couple of sheet metal drills that were offhand ground from standard twist drills. I use this style of drill a lot to cut clean holes for elctronic chassis. Shown are a 3/8 and a 7/16 diameter size. The drills are substantially different from the spur-point woodworker's drills in that the entire length of the cutting edge does cut, and the outside of the edge breaks thru the sheet metal first, cutting out a slug. The woodworker's type does most of its cutting on the lip, the rest of the edge just acts as a chipper. These drills *must* have a pilot hole to work into, and like to be used with a lot of pressure behind them, with a large feedrate. Grinding them by hand is a bit of a trick. I hope that folks can get a feel for how it is done by looking at the photos, but the only advice I can give is that it really is like a regular twist drill point, where the included angle of the lips is slightly negative, compared with the standard postive 60 degrees. Jim