hei'ya Shorn, welcome to the forum,
great first post, loads of different reasons-
for doing things one way or another,
it depends on where you want to get to,
as an end product
see att-prt fileSW2013 to get started
hope this helps you, have a good'n kelef
hole spacing.SLDPRT.zip 56.1 KB
One way is to place a centerline down the middle of the surface, fully define the first circle, then mirror it about the centerline. While I avoid linear patterns in sketches, mirroring works well (except with arcs, for some reason) and I use it often.
Similarly, you could place both circles, place the centerline, then Ctrl+select both circles and the centerline and apply a symmetric relation, which is effectively the same thing as the mirror.
A third option without using the centerline would be to place construction lines for both circles, as I have below on the right side, and apply equal relations.
This is one of those questions that has a bunch of right answers. Another way to align them is to use a centerline between them. I like doing this and then using another line to select the midpoints which makes them equal distance from the edge like the others.
You can also just make the center points horizontal.
It all comes down to end use and what you find works best for your modeling.