Sketch quickly and accurately in SolidWorks... with Grid / Snap

Understandably, SolidWorks users generally prefer defined sketches to ensure the stability of their CAD model.  However, when it comes to initially sketching splines for example, oftentimes an early or preliminary sketch may be comprised of both defined and undefined points.  This mixed approach lends itself well to developing a working sketch while still retaining some flexibility to manipulate the sketch as desired.

Another and perhaps more flexible approach toward developing a preliminary sketch however, could be to set SolidWorks System Options and Document Properties to enable Grid and Snap.  An often overlooked carryover from 2D CAD systems, the Snap-to-Grid method provides a convenient means for quickly drawing a sketch with relative accuracy, while also leaving the entire sketch free to manipulate.

The preliminary spline sketch shown here is an example of a sketch type that lends itself well to the Grid / Snap approach.

Spline sketch utilizing SolidWorks Grid / Snap option setting

By setting the Document Properties - Grid/Snap - Major and Minor grid spacing options to a preferred measure of detail, the ability to easily snap sketch points with accuracy and proportion quickly becomes evident.  

So the benefit of using the Grid and Snap options is really during the initial development of a sketch.  Rather than early on, going back and forth editing dimensions simply to tweak coordinates, the Grid and Snap options allow a user to save time and effort before committing to defined dimensions.  

Later, when it becomes readily apparent and prudent, the sketch can be defined with dimensions.  With the sketch then defined, the Grid and Snap options can easily be disabled.