You can split the workpiece by using a parting surface or mold volume to create the core and cavity volumes of the mold model.
• Split the workpiece using the All Wrkpcs split option.
• A new mold volume is created equal to the workpiece volume.
– Reference model geometry subtracted.
• The volume is split into one or two volumes.
– Use a parting surface or other volume.
Figure 3 – Split Mold Model Cavity Volume
You can split or divide the workpiece with the All Wrkpcs split option by using a parting surface or a mold volume. When the workpiece split is performed, Creo Parametric calculates the total volume of the workpiece and creates a mold volume from it. The system then subtracts, or trims, the reference model geometry and any mold features such as gates, runners, and sprues from the workpiece volume and creates a Refpart Cutout feature in the model tree (this Refpart Cutout feature displays in the model tree differently than a reference part cutout operation that is performed on a mold volume).
The remaining mold volume is then split at the specified parting surface or mold volume. The system trims the amount of workpiece volume to one side of the parting surface or mold volume and turns that volume into its own mold volume. If applicable, the system also trims the amount of workpiece volume on the other side of the parting surface or mold volume and turns that volume into its own mold volume. A simple mold model containing only a core and cavity is a typical example. One of the mold volumes becomes the core, and the other the cavity.
One Volume or Two?
For each split operation you must determine how many resultant mold volumes are to be created by specifying one of the following options :
• Two Volumes — Splits the workpiece into two mold volumes.
• One Volume — Splits the workpiece into a single mold volume, discarding the other portion. You must specify which portion you want included in the mold volume. You can do this using the Island List. The Island List enables you to select which portion to include in the new volume. When you cursor over an island in the list, the corresponding geometry highlights blue in the graphics window.
Regardless of how many volumes are created, the system prompts you to name each one. You can determine the volume to be created by shading it. The system hides all the other volumes at this time, and creates a mold volume with the name you specify.
Workpiece Splitting Guidelines
Consider the following guidelines when splitting the workpiece:
• A split operation in a mold model using the All Wrkpcs option is typically only performed one time.
• Splitting a workpiece does not modify its geometry. Whenever a workpiece is split, the system copies the volume occupied by the workpiece and creates a mold volume from it.
• If you split a workpiece by a parting surface, the system modifies the existing volume. That is, a volume is split and either one or two volumes
are created in place of the original volume.
• Splitting the workpiece with parting surfaces ensures that these solid mold components add up to the desired volume, with no extra or missing pieces.
• If you split the workpiece by a parting surface, the parting surface must completely intersect the workpiece.
• If you split a workpiece by another volume, the original volumes are not modified. Rather, the original volumes are copied and then split. For
example, if you use the Mold Volume, Two Volumes option and split mold volume A using mold volume B, there will be a total of four mold volumes after the split: original volumes A and B, and new volumes C and D. One of the new mold volumes C or D will be identical to the splitting mold volume B. As a result, you should use the One Volume option when splitting by a mold volume. This way, when you split mold volume A with mold volume B, you end up with a total of three mold volumes: original volumes A and B, and new volume C. New volume C is equivalent to volume A minus volume B.
Using the One Volume option avoids redundant volumes and keeps the number of mold volume features down in the model tree.
• Name all resultant mold volumes appropriately, as this will help you determine which mold volumes to create solid mold components from later on. For example, if the mold volume will become the core mold component, name it “core_vol”.