When a design is imported into WAM, it is simply a set of lines and curves previewed in white. In order for your parts to cut properly, WAM needs to determine which side of the line to cut. This is known as a Cut Path and comes in 4 different styles.
Before I go into details regarding a Cut Path, there are 2 prerequisites for WAM to determine a cut path successfully.
- In order to determine opposite edges on a line, an enclosed shape is necessary. Please make sure the shape is a closed loop - otherwise, how do you know which edge belongs on the inside vs outside?
Another example is due to unenclosed lines within CAD. I have drawn a rectangle with my own lead-in tail. The rectangle appears to be closed when I drew it in CAD, but the nodes along the line never connect. No matter which cut path I assign to the shape in WAM, it cannot discern an edge - so the only possible outcome is to cut it center-line.
If no white line can be seen during the cut path preview, that means a center-line cut path is being used. The green line represents the cut path, so the cut takes place directly on top of the white design line.
- Additionally, offsetting the kerf of the water jet is necessary for parts true to design size. The kerf of the water jet is approximately 0.044in/1.2mm, so this must be accounted for to give a cut part accurate dimensions. The default offset value in WAM takes care of this for you! (Default offset values are 0.019in or 0.48mm)
Here is an example of an offset to achieve an accurate cut on the outside edge:
Here is an example of an offset to achieve an accurate cut on the inside edge:
There are 4 cut path options in WAM. In order, they are:
- Outside Cut Path. If precision is your priority, the cut path must take place along the outside of the part. The Outside Cut Path will automatically offset the kerf to the outside of the part appropriately!
- Additionally, if any enclosed shapes exist inside of another, the offset side is automatically swapped in order to continue to give the most accurate cut out of the design part!
Outside Cut Path
Outside Cut Path with Shapes Inside Another
- Centerline Cut Path. As you can imagine, this cut path places the kerf right on top of the design line. Essentially, this means you will get a smaller part than designed - the inside of the kerf will eat through the design, while the outside of the kerf will eat through the remaining material. Centerline cutting will take place along the center, no matter how the shapes are laid out or organized! This path will be used as default for any lines that are not a closed loop!
Below is a close-up example of the water stream/kerf:
- Inside Cut Path. If a precise stencil or holder is required, cutting on the inside of a line is required! (Think of this cut path as the exact opposite of Outside Cut Path) The Inside Cut Path will automatically offset the kerf to the inside of the part appropriately!
- Additionally, if any enclosed shapes exist inside of another, the offset side is automatically swapped in order to continue to give the most accurate cut out of the design part!
Inside Cut Path
Inside Cut Path with Shapes Inside Another
- No Cut. This option is used for referencing purposes only. In order to help a user place a fixture or jig in the appropriate location. If this option is ever selected, WAM will display an warning or error message to alert the user.
