Creating setups
All CAM operations in Fusion are contained within a setup. A setup tells Fusion how a piece of stock is positioned on the bed of the CNC machine by specifying a coordinate system and an origin point for the stock.
Setups also serve an important secondary function: they group cutting operations together. Partly this is a convenience, allowing you to encode several cutting operations in a single instruction file. Load them up and let your CNC machine do the rest.
Grouped operations are also essential for rest machining. Rest machining is simply an operation that cuts only the material that wasn’t removed by previous operations. Rest machining is especially critical for 3D machining, where machining times can become unmanageable long.
Creating a setup involves three steps:
- Choosing the parts of your design that you want to include in the setup.
- Indicating the X, Y, and Z axes, and also the origin point.
- Indicating how far your stock extends beyond the borders of the pieces you are machining.
Create a new set-up by choosing CAM > Setup > New Setup.
Setup tab
This tab allows you to specify the orientation and origin point of your stock, as well as the bodies or components you wish to machine.
Work Coordinate System (WCS)
Orientation: Select Z axis/plane && X axis
If you followed my advice and set up a work coordinate system for your model that matches your CNC machine, then you can choose “Model orientation” and you’re done. Otherwise, choose one of the next three options, which are roughly equivalent, and adjust the other WCS parameters accordingly.
Z axis: Select either a plane that is perpendicular to the Z axis (such as the stock top), or an axis that is aligned with the Z axis (such as a vertical edge of the stock).
Flip Z Axis: (optional)
Fusion will guess the direction in which the Z axis is ascending. If Fusion guesses wrong, check this box to flip the direction of the axis.
X axis: Select an edge in your model that is aligned with the X axis.
Flip X Axis: (optional)
The X (red) axis should be pointing in the direction of ascending X values. If not, check this box to flip its orientation.
Origin: Stock box point
The other options are also valid, and fairly self-explanatory. You need to set an origin point. All that matters is that you pick one that you can zero your bit on.
Stock point: Choose the lower-right point on the top edge of the stock
Or choose a different point. You can put your origin point wherever you want, as long as your zero your bit at the same point.
Model
Model: Select the bodies that contain your cuts.
Stock tab
Stock
Mode: relative size box
You can choose a fixed size box if you know the exact dimensions of your stock, but usually the default is fine. The default option is to define the stock dimensions relative to the model you are machining.
Stock Side Offset: 0.5 inch
Choosing a value of at least bit diameter * 2 makes it easier to see your cuts during simulation.
Stock Top Offset: 0
You generally only want to include a top offset if you are planning to face the stock before machining your piece. If you are not planning to do any facing, make sure to set this to 0. Otherwise your cutting operations will all have incorrect Z values.
Dimensions
These values are automatically calculated based on your prior selections. Review them to verify your selections. If the Z value is way too large, for example, you probably didn’t properly orient your axes (i.e., Fusion thinks your X or Y axis is the Z axis). If the Z value is close but not quite right, you might have forgotten to set the ply of your stock correctly, or accidentally added an offset to the top of the stock. In short, make sure these values describe the dimensions of the physical thing you are making. If they don’t, figure out why before proceeding with any cuts.
Post Process tab
The defaults on this tab are all fine.
