Barrel cutting tools are being used more and more by manufacturers because of the unique advantages they offer. These tools, with effective radius between 50 and 1000+ mm, help you achieve the desired scallop height with less cutting passes. This can shorten machining time, while improving surface finish.
Barrel cutting tools are used for various machining operations, including finishing of flat and slightly curved walls, as well as deburring. NX CAM software supports programming using barrel mills enabling you to improve your machining efficiency.
This tech tip explains the best practices about using barrel mills and it also highlights some of the new functionality in NX CAM 12.0.2.
Below, we will describe how to define barrel cutting tools and how to use these tools for NC programming.
In NX CAM 12.0.2, we added a new tool type, Tangent Barrel, which simplifies the user interface. As shown in the example below, the new settings enable you to easily define and use barrel mills for NC programming.
Note that in the older versions of NX, you can define these tools as ‘BARREL’ or ‘MILL_10_PARAMETER’ but it requires some settings that are not always obvious from the vendor catalogs.
Taper barrel mill tool needs to be defined using a ‘MILL_10_PARAMETER’
Note: MILL_10_PARAMETER does not allow to define the upper fillet, so the tool shape follows the untrimmed corner. This fillet is not a recommended working area of the tool and this representation assures we are always on the safe side. Note that this is not a functional limitation.
To help you find the key settings, we’ve created the attached NX part (.prt) file:
User fills in the data from the vendor catalog into the expressions (blue), and it will generate a solid body of the tool with 3 PMIs to be used in the CAM tool definition. Follow the green arrows to set those correctly when building the 10 parameters tool.
In future releases, we are planning to add a new tool type in NX to simplify the definition of these tools.
Using data provided by Fraisa, we created some of their tools in NX:
These predefined tools let you browse and select a tool:
Attached prt contains several tools defined in NX.
NX CAM software supports barrel mills in Surface Contouring (Fixed and Variable Axis) for long time. In Variable Axis, it is recommended to use the “Swarf Drive” option:
Set the tilt angle as recommended by the vendor (α/2):
With appropriate increase / decrease of the tilt angle, you can control the contact point on the tool (Ring Height):
Tilt angle = 18 Deg – Contact closer to tip
Tilt angle =15 Deg – Nominal Angle
Tilt angle =10 Deg – contact closer to shaft
Starting with NX CAM 12.0.2, the Multi-Blade Blade Finish operation was optimized to support these tools for blisk machining.
The Guiding Curves capability in the next release will be expanded to support barrel mills. The user will be able to directly control the Ring Height, Swarf angle and use Tilt tool axis for avoidance and smoothing. We will make it available through the Early Adaptors Program (EAP). In future, we will develop a set of operations targeted to machine pockets using barrel mill tools.
Please contact me directly at email@example.com if you need more information.
Before you go, check out this new two minute video made by our friends at Fehlmann AG and FRAISA. The video shows a nice machining cut that highlights the Adaptive Milling toolpath as well as 5 axis finishing with a barrel tool -- using NX CAM software!