SolidWorks 2011 Assemblies Bible - Matt Lombard [183]
The final steps for the parting surface are to knit it together into the core surface and the cavity surface. Follow these steps to accomplish this:
1. Use Knit to knit together the Boundary surface and the Parting Surface body resulting from the manual mode process.
2. Make sure this knit surface goes into the Parting Surface Bodies folder, as shown in Figure 21.18.
FIGURE 21.16
Setting up the Boundary surface
The parting surface is larger than you need it to be, and it is not a pretty shape, but neither of those issues matters.
FIGURE 21.17
The completed Boundary surface
FIGURE 21.18
The completed Parting Surface and Feature tree
Tooling split
Assuming either you have completed the parting surface manually or through the SolidWorks Mold Tools, the next step is the tooling split. If you complete the parting surface manually, make sure it is knit together as a single surface body, and then in the Surface Bodies folder, drag the knit surface into the Parting Surface folder. The Tooling Split feature does not work unless all the surface bodies are in their correct folders.
Figure 21.19 shows the PropertyManager for the Tooling Split feature, along with a preview of the feature. The feature will produce two solid bodies, representing the cavity and core blocks of the mold. This model is included on the DVD with the material for this chapter.
FIGURE 21.19
The Tooling Split PropertyManager and the finished product
A tooling engineer would probably change a few things about the layout of this split, but for learning how the tools work, this is sufficient. The parting line of the front part of the device should probably face forward instead of up to reduce the amount of vertical steel in the mold. To send the cavity and core blocks to a shop for mold building, you will probably want to separate the multi-body part into individual part files.
Note
To check the cavity and core blocks to ensure that they make the desired shape, make a new block that is larger than the original part, ensuring that the Merge Result option is deselected. Then use the Combine tool to subtract the mold parts from the new block. Finally, use the inverse scale to shrink it back down to the finished part size (1⁄2 the original scale factor).
Using the Core feature
The following example uses the Core feature to create a set of core pins. All the standing steel that creates the counterbores for the screw bosses is made from separate replaceable pins. You can use many techniques to locate pins rotationally. This is not a lesson in mold design, but only in mold modeling techniques.
You can either pre-create a sketch or just make a sketch when the Core feature asks you for it. The Core feature is looking for a sketch that will cut out the block of mold material from which you want to make a core. Again, you can use this for side cores or core pins. In this case, you will make several core pins.
To start, activate the Core feature; then sketch circles centered on each of the screw boss cores in the cavity body. When you exit the sketch using the Confirmation Corner, SolidWorks prompts you for an extrusion depth for the sketch to create the feature. The Core PropertyManager and the feature preview are shown in Figure 21.20.
FIGURE 21.20
The Core feature
Again, you can save out these core pins as individual part files. You can use similar techniques to create side cores, lifters, or other types of side actions.
Intervening Manually with Mold Tools
You can conduct the entire mold modeling process manually, without using any of the semi-automated tools from Mold Tools. You may even come across situations where you do not need to use surface modeling at all. These situations will often involve parts with a planar parting line, with no shut-offs or cores.
Experienced mold designers tend to use different techniques,