When sketching, should i use splines or 3 point arcs?

And which is simpler to use?

3 Answers

arc - geometry is better unless you need a flowing surface

I agree with Robert. I work in manufacturing and one of the problems we often face is that when 2D views are generated from 3D models, there are often splines created. This is a problem because most CNC controllers cannot handle splines, in particular simple controllers that have conversational interfaces. These interfaces only allow the operator to enter arc or circle data, usually center point, start point and end point or the radius of the arc as a blend between lines. Even some older CAM software can't handle splines at all, they just refuse to recognize them. We are often tasked with redrawing the spline as 3 point arcs that approximate the spline.

Depends what you are doing. Arcs are better for certain applications as has already been mentioned. But if you are doing something like a car body only splines will work.