Cutting/Beveling tools operate on all paths that are specified as contours in the file. When a plain cutting tool is used, it is a straight forward operation.
DSTV also specifies making weld preparations on any given edges of a contour. When a beveling tool is used, the importer generates extra geometry for on which beveling tool is applied. All of the calculations involved in creating bevel geometry such as offsetting are automatically handled.
Currently the following types of beveling are supported:
•K-bevel
•Negative bevel
•Positive bevel
If there are bevels but not beveling tool is set it the ignores bevels and creates a straight land cut.
Example showing (in 3D view) the outside edge of the part. This is variation of the above part, a positive bevel with a land. The beveled path is automatically offset to account for the angle and depth of the cut. The highlighted path (in red), is an open path that represents the land portion and it is also the original outer edge of the part.
Example of the same part, but this time with a K-bevel (positive bevel + land + negative bevel). The negative bevel (highlighted in blue) is an open path created by the auto process and automatically offset to account for the angle and depth of the cut.
Offsetting
Offsetting is required when positive beveling is used. To see why, imagine the cutting torch making a positive beveled cut on the outside edge of a part: the final size of the part will be larger than the outside edge because the bottom of the part will be visible when looking down. To correct for this, offsetting calculates the offset depending on the bevel angle and part thickness, this is automatically performed on all paths.
In some cases however, it is desirable to create pre-offset paths, and not have the bevel processing be offset again. This is created by setting 'Geometry Defines Top Path' property to true on the bevel process (only applicable to positive bevels).
Extra geometry is automatically created for weld preparations. Since this geometry is already calculated with the correct offsets, the 'Geometry Defines Top Path' property of the processing is automatically set to true.
See Also