Making CNC Turning Easier

A good example is the new 8050TC lathe CNC from Fagor Automation (Elk Grove Village, Illinois). The aim of the new design, says the builder, is to offer lathe users a CNC as simple to operate as a DRO. The new CNC offers an easy and intuitive interface, eliminating the need for a lengthy training period in order to be able to program a part.

The interface is based on the most common operations performed on a lathe—turning, facing, threading and so on. Each one of these operations is selected via a specific key and it is designed in such a way that all the operator has to do is enter the machining conditions and part geometry data, which can be obtained directly off of a typical part print.

This sort of control makes sense in a number of typical manufacturing applications. For example, prototype manufacturers are often presented with relatively complicated parts, but that are made in very small quantities, perhaps only one. An easily programmable CNC can handle complicated geometry that's difficult to cut manually, and also keep quantity-of-one jobs out of the CAM department.

Moreover, many companies with operators who are skilled in machining, but not programming, need an easy-to-use CNC in order to save on machine setup time. With them in mind, an interface has been developed which allows operators to enter part geometry the way it appears on a print, without having to use any programming language. All that has to be done is enter the operations required to make the part (turning, facing, and so on) sequentially and with the proper coordinates. All these operations may then be graphically verified on the CNC monitor before finishing the part program.

For longer run manufacturers, the CNC offers an advanced profile editor (capable of solving part geometry with undefined coordinates, tangency, and so on) or the choice of using ISO and high-level language programming.

The CNC spans an operational range from emulation of a manual lathe to full production turning. In jog mode the control shows the basic process information including position of the axes, feed rate, spindle rpm and selected tool. In this mode, the operator may perform simple machining operations in a conventional way by means of electronic handwheels. Selected tools are indicated by icons on the screen that show the shape of the tool to help avoiding accidental errors.

The CNC also offers simple control of spindle speed, turning direction and orientation. It includes operation at constant surface speed, operation with live tools, operation with jog keys (to move the axes manually) and operation with handwheels.

It also offers a number of tool management features. To establish tool offsets, the operator just has to secure the part, enter its dimensions and touch it with the tool. Then the CNC automatically collects all the necessary data to run without errors. And there is graphic assistance to enter tool geometry.

Automatic cycles are designed to better adapt to the usual working methods of a shop. The machining process is divided into a certain number of operations represented by icon keys with LEDs to indicate whether they are activated or not.

The CNC offers quite a wide variety of automatic cycles including turning, facing, rounding, taper cutting, threading, grooving, drilling and face tapping. Each one of these cycles may be simulated by using the graphics key on the operator panel in order to verify that it will run properly.

Also, profiling cycles offer several levels, depending on the complexity of the part. In Cycle 1, to enter the shape of the part, all one has to do is know the locations of its theoretical corners (up to a maximum of 12 points) and enter the desired corresponding radius or chamfer conditions. In Cycle 2, it is possible to "tell" the CNC to solve the undefined variables that come up—for instance, tangency. The program editor searches and calculates, in a totally transparent way to the user, the possible solutions according to the known data, thus eliminating the need for additional manual calculations. MMS