b'Extended reach is not just how long it isbut how long it is in relation to the tool diameter.a 2"-dia. tool at 14" length is only aextended-reachtoolholdersisThe tool steel itself, along with 7-1 ratio, which is not particularly ex- achieving suitable rigidity. The lon- the Rockwell hardness of the tool tended length. ger and thinner the holder, thesteel and the substrate, all relate more likely that bending forces willto the rigidity of the tool assem-Extended-Reach Machining cause runout. bly, Bishop said. Lets say you try Bishop said customers typically use extended-length holders to reach past fixtures, obstructions or part features to machine other part features beyond. For those applica-tions, he recommends keeping cut-ting forces light to minimize radial or axial radial deflection. M4000The cutting tool chosen could be more positive or high shearing,Efficiency across he said. Or we can apply toolpaths, such as high-efficiency or high- all generations.feed milling, which are different ap-proaches to speeds and feeds and depth of cut.Trochoidal milling, a form of high-efficiency milling, is one option for extended-length toolholders be-cause it exerts less stress on the spindle. The idea for a 1"-wide slot is to use a smaller-diameter cutting tool, like a " milling cutter instead of a 1" cutter, and then feed the cutter forward in a circular toolpath open-ing the slot to the 1" width instead of creating it with one big hog pass thats 1" wide, said Mark Backus, product specialist for machine in-tegration and tooling systems at Sandvik Coromant Co., Fair Lawn, New Jersey.ThemainchallengewithPowered by TigertecSilver M4000 is the universal system for all users who want to have as many options as possible when milling. The M4000 range can master all machining tasks with our most efficient indexable insert powered by Tigertec Silver. Whether it is a shoulder milling cutter, high-feed cutter, chamfer milling cutter, or T-slot milling cutter, the about the authorsquare system indexable inserts can be used across the entire M4000 range. Save time and money, and invest in the future. As the Walter Green seal shows: The Holly B. Martin isM4000 is fully CO 2compensatedfrom raw material to manufacturing to storage.a science writer and technical copywriter based in Winchester, Virginia. For more information, visitwww.walter-tools.com/uswww.hollybmartin.com.ctemag.com/cteguide.com55Toolholders.indd 55 6/13/19 4:47 PM'