Cutting corners out of current stock

[Farrgolf (Dick Farrell)]

New here. I created a sign out of 3/4” red oak for my second project. Happy with the sign, but now would like to fillet corners from sign. How do I cut off only the corners without having a tool path around complete stock? I don’t know how to create just these four individual tool passes. Then I would like to create an inside outline of entire sign 1/4” from edge. Hope this makes sense

Shapeoko Pro XXL

[WillAdams (William Adams (Carbide 3D))]

Draw a rectangle with the desired corner treatment:

Offset to the outside by tool diameter plus 10%:

Apply

Draw in a square which isolates one of the corners using ctrl (or command on a Mac):

Then use that square to draw a larger one:

centered on the corner.

Then select the original rectangle and duplicate it, then select it, and the offset geometry and the larger square:

and use the “Trim Vectors” command to isolate what you wish to cut:

If need be, use Node Edit to delete anything which won’t delete:

Done

Select the open geometry which isolates where one wishes to cut.

and use “Join Vector” to close it:

Yes

Apply a suitable toolpath:

and verify the cut:

Then duplicate the geometry 3 times:

and use the Mirror or Rotate tool(s) to adjust each for orientation:

and drag each into position:

using a Node to snap against the original rectangle.

Attached as a v7 file.

flipped_fillet_corner.c2d (76 KB)

[mhotchin (Michael Hotchin)]

Can also do this using Boolean Subtraction, with no Node Editing.

Start with the desired profile:

Offset buy bit width + ~10% (I used .300)

Draw a rectangle than covers the top and bottom portions you don’t want:

Select the inner boundary, the outer bounday, and the rectangle (last!). The rectangle is now the ‘Key’ object:

Boolean Subtract:

Repeat with a horizontal rectangle:

For each corner, select the outer boundary then the inner boundary, then boolean subtract:


Repeat for each corner, then pocket each area:

You could also draw both rectangles first, Boolean Union to create a cross-like shape, then use Boolean Subtract with that.

Now treat each corner as above.