CAM ToolShape

Description

ToolShapes are a core part of the CAM Tools system. ToolShapes are the templates from which ToolBits are created. They represent the specific physical shape of a tool. A ToolShape does not completely describe the bit - for that some additional parameters are needed which will be added when an actual bit is parameterized from the template.

Initially ToolShapes are just FreeCAD documents with a single Body created from the Workbench PartDesign Part Design workbench.

Creating new ToolShapes is an advanced topic. The most commonly needed ToolShapes already exist and are provided with the FreeCAD installation at:

  • On Linux it is usually /usr/lib64/FreeCAD/Mod/CAM/Tools/Shape

  • On Windows it is usually C:\Program Files\FreeCAD\Mod\CAM\Tools\Shape

  • On macOS it is usually /Applications/FreeCAD.app/Contents/Resources/Mod/CAM/Tools/Shape

They are:

:: ballend.fcstd
bullnose.fcstd
chamfer.fcstd
drill.fcstd
endmill.fcstd
probe.fcstd
slittingsaw.fcstd
thread-mill.fcstd
v-bit.fcstd

These can be found in the Mod/CAM/Tools/Shape/ subdirectory where FreeCAD was installed.

Usage

  1. Create a new FreeCAD document.

  2. Open the Workbench PartDesign PartDesign Workbench.

  3. Create a Body and give the Body a label you want to show up in the bit selection.

  4. Create a PartDesign NewSketch Sketch on the XZ-plane and draw half the profile of the bit.

  5. Constrain the bottom most center of the bit on the origin (0,0). This will be the center of the axis on which the G-code will rotate the bit.

    • Note: Do not add dimensional constraints at this time.

  6. Close the Sketch.

  7. PartDesign Revolution Revolve the Sketch around the vertical Sketch axis.

  8. Open the Workbench CAM CAM Workbench.

  9. Select the Sketch in the Tree View. This ensures that the PropertyBag created in the next step will be nested in the Body.

  10. Select the CAM  Utils  PropertyBag option from the menu.

  11. A PropertyBag named Attributes is created. This PropertyBag will be used to control the dimensions in the Sketch.

  12. Double-click the PropertyBag in the Tree View.

  13. The Property Bag task panel opens.

  14. Click the Add…​ button.

  15. The Create Property dialog opens.

  16. Create a property named Diameter. This property is mandatory for ToolBits. Property names are case-sensitive and may not contain spaces.

  17. Select Shape from the Group dropdown list.

  18. Select the appropriate Type.

  19. Optionally specify a ToolTip.

  20. Click the OK button.

  21. In the Property Bag task panel enter a value for the Diameter property.

  22. Similarly add all other required properties.

  23. Click the OK button in the Property Bag task panel when done.

  24. Double-click the Sketch in the Tree View.

  25. Add dimensional constraints and apply the properties from the created PropertyBag. For example to apply the Diameter property:

    1. Double-click a dimension.

    2. Click the Bound expression icon.

    3. Enter [Attributes].Diameter in the Formula editor.

    4. Click the OK button twice.

  26. Repeat this until the Sketch is fully constrained.

  27. Save the FCStd file where FreeCAD expects to find ToolBit files. See Description above.

    • Note 1. If you are denied access to the folder on Windows, start FreeCAD in ADMINISTRATOR mode.

    • Note 2. The Body of the ToolBit must be the first object in the Tree View. These instructions ensure that this is the case.

Tool Thumbnail Images

ToolBits will have a small icon image of the tool in the Tree View if the file is saved with thumbnails active.

Important notes:

  • Before saving the document make sure you have Save Thumbnail selected, and Add program logo deselected in FreeCAD’s preferences.

  • Also make sure to switch to Front View and Fit content to screen

  • Whatever you see when saving the document will end up being the visual representation of the template