I dont have the manual in front of me, so I don't know if this will help you out or not. While in a SW part, under "Help" search for "equations". There are several topics to choose from. I am not sure if this is more info than the manual.
What kind of equation are you interested in adding to your part? Or are you just wanting to gain knowledge of the equation option.
FYI, if you are using the API, then dont bother using equations. SW dumps each equation to a temporary one-line VBA macro anyway, then executes each in turn.
Scott, I'd like to see your reply in the FAQ area, but am not sure how to do that, and in any case, I think you should get the credit for it (it was exactly what I needed)
Here is something else I need: I have a need to define the wall thickness of a part before I actually need to use it. I haven't seen anything that indicates I can create a variable name in the equations then use that name in another equation.
When I enter Eq. 1, I get a message that it's an invalid equation.
Any thoughts would be appreciated
BTW, the counterbore is being put into a preform which is then split in half with each half shelled out in separate part files based on the same preform (I didn't create this group of files, I just have to deal with it). I'm sure there are other ways to skin this cat (multibodies for one), but due to the complexities of each half, I'm focused on not redoing the model, just making smart incremental changes
Combining both the answers from Scott and The Tick, I discovered a reasonable solution.
Create a Surface Offset, then, using Scott's double click advice, capture the feature dimension and rename it "Wall Thickness", and add it to the Equations list. Leave the offset surface in place as a piece of reference geometry.
Create another one, repeat the process, and relate it through an equation as a percentage of the Wall Thickness.
The two offset surfaces convey the intent of the thing, and can now be used to drive the acutal Shell feature and attendant CBore dimensions (even if they aren't restricted to the surface used to create the offset, but lay elsewhere on the shell).
You may also want to look up link values ("link --> dimension values" in SW2003 help). This is another way to apply common values across many dimensions.
"Great ideas need landing gear as well as wings."--C. D. Jackson
DT (Design Tables) are used to help with equations in SW. I use DT to control my models over Equations because I can use Excel formulas to control my dimensions. I (you) can take that a step further by adding VBA callouts to your models with equations and a DT. It gives it some Automation. DT are probably not needed for smaller files, but then again they might be depending on your need.
You can find some VBA and DT examples at my site -
You could also use offset planes rather than offset surfaces, which would probably create a smaller file and less likelyhood of future surfaces complications.