It should be obvious to anyone who has ever washed a driveway or patio with a garden hose: For the best results, you must keep the stream of water precisely where it's needed. The same principle applies to delivering coolant to the cutting zone. Until recently, most shops used coolant lines or tubes that the operator or setup person manually positioned to deliver coolant to the tool-workpiece interface. However, the method was not foolproof. The operator may move the coolant line out of the way to index an insert, clear chips or adjust the setup and forget to reposition it. The tool itself may get in the way of the stream. In any case, the coolant doesn't get to the place where the tool meets the workpiece and for all practical purposes the machine is cutting dry. Dimensional accuracy and surface finish suffer as a result, and tool life is significantly shortened.
One solution to the problem is the Point Blank coolant-fed OD turning toolholder developed a few years ago by LMT-Fette (Cleveland, Ohio). The toolholder's coolant nozzle shoots coolant where it's needed—on the cutting edge. In addition, the size of the nozzle's orifice maximizes coolant velocity, resulting in improved chip evacuation, increased tool life and improved surface finishes, even at higher cutting speeds.
The original toolholders included both 3/4- and 1-inch square shank tools, for the right or left hand, and accepted all common turning inserts. They were so well received that the company has expanded the line and widened its areas of application. Point Blank is now available in three new configurations for OD turning and ID boring on Swiss-style machines.
The toolholders come in a range of sizes, including 3/8-, 1/2-, 3/4-, 1- and 1 1/4-inch square shank tools, for the right or left hand. They are also available for all common turning inserts, including CNMG, WNMG, VNMG and DNMG styles. Boring bars are now available in 1- to 1 1/2-inch sizes and in negative 80-degree geometry. Because the toolholders are made to ANSI specifications, they can be used in place of conventional counterparts without having to adjust existing machining programs. They include industry-standard hardware that make conversions to the toolholders simple and cost-effective. They also are suitable for all roughing and finishing applications.