http://www.todaysmachiningworld.com/forum/topic/tapping Brought to you by Todays Machining World en-US Mon, 06 Sep 2010 15:36:05 +0000 http://bbpress.org/?v=1.0.2 q http://www.todaysmachiningworld.com/forum/search.php http://www.todaysmachiningworld.com/forum/topic/tapping#post-19 Tue, 21 Oct 2008 17:23:03 +0000 Anonymous 19@http://www.todaysmachiningworld.com/forum/ <p>There is no off-the-shelf answer to your problem that I know of, but there is a simple solution that works quite well: It’s called a “pivot cutoff.” You’ll need to grind your own tool from a brazed carbide stick tool or an insert type grooving tool.</p> <p>The idea is that you will grind the leading edge of the cutoff tool at an angle that is perpendicular to the point on the work. For strength and clearance, you will grind the trailing edge of the tool so that it will clear the point being generated by two degrees. </p> <p>Picture the tool grinder with the blank groove tool’s cutting edge oriented parallel to the grinding wheel. You will need to rotate the tool clockwise 60 degrees to grind the leading edge of the tool. The trailing edge will be ground by rotating the tool counterclockwise by 32 degrees. This will give the tool tip an included angle of 88 degrees, resulting in a strong edge.</p> <p>Programming the tool is a simple matter of turning the angle in one pass. Usually there is no benefit to any roughing. The weight, length and diameter of the work will dictate the speed and feed rate you will use with this tool. The longer and heavier the work, the slower the spindle speed will need to be. Sometimes it helps cycle time to break the tool path into two segments; run the first segment at a higher speed and feed rate. Then, drop the rpm and feed lighter as the tool approaches spindle centerline. </p> <p>Dan Murphy<br /> Regional Sales Mgr.<br /> Tsugami/Rem Sales </p> http://www.todaysmachiningworld.com/forum/topic/tapping#post-18 Tue, 21 Oct 2008 17:20:49 +0000 Anonymous 18@http://www.todaysmachiningworld.com/forum/ <p>I have a job in which I need to drill and tap one end of a part and cut off at the other end to a sharp point at a 60 degree included angle. I don’t have a sub-spindle lathe and it would sure be nice to drop off the part complete. I’ve tried a variety of cutoff tools, but no matter what I try, the part breaks off with a large cutoff burr. Is there a tool that can cut off to a sharp point? </p>