This one is for you 3D. Let us try a little more complicated edit which SE breezes through.
Here we have a “Magazine” that feeds capsules into a machine that will fill them.
There are feed problems with the original factory parts and we are changing the end of the magazine assembly to a rounded instead of angled feed end. While doing so and being in a hurry and having three different change requests thrown at me I see a .02″ offset that could conceivably hang a capsule up. Now I think the chances are really slim this would happen but we are going to eliminate this. Now as you look at this part remember that both ends could have been just as complicated and the edit would work in the same exact fashion so this is not a situation where I am fudging things by leaving the XYZ zero point on a simple set of corner faces. It is just how this part is made and since it is a real world part how it is going to stay.
Now keep in mind as you work in Synchronous the direction you assign to dimensions is important and good habits here will save you trouble later. I assign (lock down) directions where ever possible radiating out from my X Y Z zero point. I also assign the right rear top corner of the part whenever possible ( or the imaginary corner of the block of stock this will be cut out of if there is a corner round or radius at that point. ) as XYZ zero because someone will have to make this thing and you might as well anticipate how they will have to set up to cut it. One of the BIG things to remember here is to check and see that you have as few dimensions as possible to make the part work. You will find that there is a tendency to apply a dimension twice to the same feature as you work without realizing you did so. For example it is easier than you think to have a block and assign a “z” dimension twice to different corners because you did not quickly see the first one. One of the two can cause you problems especially if they are directed to be locked down for different relationships. So look twice and clean these things up or better yet learn not to do it. When you are working with faces and features that can interrelate you can cause problems that can be solved but may take extra trouble to do so. If you want certain behavior to happen just turning live rules off to complete your edit can defeat this and though it is the quick and easy answer to almost all problems caused by dimensions you want to learn to work with rules when you need to have predictable behavior in selected features. Holes constrained as a set for instance where you don’t want to have to pick each feature for an edit but would rather just click once and edit.
Let’s edit this part.