Use the Offset page to specify settings for an offset-style contour mill strategy, which creates cutting moves by offsetting the model or block.
Style — Select the type of offset.
Offset spans in contact with model — This offsets the spans in contact with the model.
This produces a toolpath which:
- Maintains constant tool load and chip production
- Maintains cut direction
- Avoids machining small or thin walled upstands
- Minimises full-width cuts.
Minimise air moves — This offsets all spans and minimise air moves.
This produces a toolpath which minimises the number of lifts and works extremely well for soft materials.
Each area is machined with one plunge at the start of the toolpath. This works well if cut direction is not important, as it is difficult to maintain cut direction if you are not allowed to lift the tool.
Maintain cut direction — This offsets all spans and maintain cut direction.
This introduces additional lifts when required to maintain cut direction. If you want to use trochoidal machining (refer to Tool Loading), you must select this option.
Remove cusps — Use this option to control both the maximum stepover and the addition of cusp removal moves. This option is selected by default, which means that the stepover is limited to the maximum flat diameter of the tool (so, a 10 mm tool with a 2 mm tip radius has a maximum stepover of 6 mm). PartMaker adds cusp-reduction moves to ensure that no cusps are left and that no tall, thin upstands are formed.
When the option is deselected, the stepover is limited to the diameter of the tool and cusp reduction moves are added only to prevent tall, thin upstands forming. This can be useful when machining soft materials where any remaining cusps will be removed by the next machining level height, as the additional moves slow down machining unnecessarily. However, additional moves to prevent the forming of tall, thin upstands are added.
These two toolpaths were created using the same tool (a tip-radiused tool with a 10 mm radius and a 2 mm tip radius), and at the same setting (a stepover of 8 mm) on the Model area clearance page.
With Remove cusps selected:
With Remove cusps deselected:
Spiral — Select this option to enable spiralling to occur (where the original offsets are closed and have one-to-one nesting).
For example, it converts this:
to this:
