SolidWorks 2011 Parts Bible - Matt Lombard [116]
Using folders
When you have a large number of fillet features, it can be tedious to navigate the FeatureManager. Therefore, it is useful to place groups of fillets into folders. This makes it easy to suppress or unsuppress all the fillets in the folder at once. Separate folders can be particularly useful if the fillets have different uses, such as fillets that are used for PhotoWorks models and fillets that are removed for FEA (Finite Element Analysis) or drawings.
Making multiple fillet sizes
The Multiple radius fillet option in the Fillet PropertyManager enables you to make multiple fillet sizes within a single fillet feature. Figure 7.30 shows how the Multiple radius fillet feature looks when you are working with it. You can change values in the callout flags or in the PropertyManager.
FIGURE 7.30
Using the Multiple radius fillet option
This may seem like an attractive way to group several fillets into as small a space on the FeatureManager as possible, but I cannot think of a single reason that would drive me to use this option. While there may be a small performance benefit to condensing several features into one, many more downsides adversely affect performance:
• Loss of control of feature order.
• A single failed fillet causes the whole feature, and thus all the fillets, to fail.
• Troubleshooting is far more difficult.
• Smaller groups of fillets cannot be suppressed without suppressing everything.
• You cannot change the size of a group of fillets together.
Best Practice
While this may be more personal opinion than best practice, I believe that there are good reasons to consider using techniques other than single features that contain many fillets, or single features that drive fillets of various sizes. Best practice would lean more toward grouping fillets that have a similar use and the same size. For example, you may want to separate fillets that break corners on ribs from fillets that round the outer shape of a large plastic part.
Another consideration is feature order when it comes to the fillet's relationship to draft and shell features. If the fillets are all grouped into a single feature, then controlling this relationship becomes impossible.
Rounding corners
The Round corners option refers to how SolidWorks handles fillets that go around sharp corners. By default, this setting is off, which leaves fillets around sharp corners looking like mitered picture frames. If you turn this setting on, the corner looks like a marble has rolled around it. Figure 7.31 shows the resulting geometry from both settings.
FIGURE 7.31
The Round corners option, both on and off
Using the Keep edge/Keep surface toggle
The Keep edge/Keep surface toggle determines what SolidWorks should do if a fillet is too big to fit in an area. The Keep edge option keeps the edge where it is and tweaks the position (not the radius) of the fillet to make it meet the edge. The Keep surface option keeps the surfaces of the fillet and the end face clean; however, to do this, it has to tweak the edge. There is often a tradeoff when you try to place fillets into a space that is too small. Sometimes it is useful to try to visualize what you think the result should look like. Figure 7.32 shows how the fillet would look in a perfect world, followed by how the fillet looks when cramped with the Keep edge option and how it looks when cramped with the Keep surface option.
FIGURE 7.32
The Keep edge option and the Keep surface option
The Default option chooses the best option for a particular situation. As a result, it seems to use the Keep edge option unless it does not work, in which case it changes to the Keep surface option.
Using the Keep Feature option
The Keep Feature option appears on the Fillet Options panel of the Fillet PropertyManager. By default, this option is turned on. If a fillet surrounds a feature