When you don’t draw an arc, SOLIDWORKS adds a radius dimension and not a diameter dimension.
I once told a supplier that it was impossible to change the dimension into a diameter.
Turns out I was wrong.
Imagine you are designing a leaf spring with a hole hinge.
A hole hinge is a super awesome hinge out of a single piece of metal, with zero play.
When creating a drawing, SOLIDWORKS will automatically show a radius dimension on the arcs that are not complete circles.
Suppose now I want to change the R3 dimension into a Ø6 dimension.
You do that in the properties menu that shows up when you select a dimension.
Click one of the two options in red. Both options turn the dimension into a diameter. I selected the option on the right.
Now you have a diameter dimension, but the position is strange.
You’ll have to drag the dimension by the anchor point to reposition it.
This is the final result:
So that was easy, wasn’t it?
Then you need to check out this article on drawing dimensions from the SOLIDWORKS help.
Or check out our add-in Drew. Drew can automatically add outer dimensions to your drawing views. Without the crappy AutoDimension.