Sorry if this has been covered before but I can not seem to find a reference anywhere.
In the Shape alternative, what do/are the G1,2 and 3 Blends about please.
Brian

Hi Brian, I didn't really tackle that in the help file because it is pretty difficult to describe without going into technical details.

Basically it has to do with smoothness.

When 2 curves or surfaces are tangent to one another, that is one level of smoothness.

But there are additional levels beyond that - for example if you have a line and then and arc meeting such that they are tangent, there is still a change in "curvature" between them.

Curvature is basically what radius of a circle a curve resembles at any given point, kind of like how much it is bending at any one point along it. If the curvature between 2 different curves is the same when they meet, that is called G2 or curvature continuity. Tangent is G1 continuity. G3 is a shared rate of change of curvature between the 2 pieces.

The options that say "Blend" mean that instead of a circular arc, there will be a somewhat more organic and arbitrary shaped curve between them, with the given amount of continuity (G1 = tangent continuous, G2 = Curvature continuous, G3 = rate of change of curvature continuous).

One other thing is that the higher types of continuity also require more complex surfaces to be built - tangent requires 4 points for each cross-section, G2 requires 6 points for each cross-section, and G3 requires 8 points for each cross section. So the geometry gets heavier as you use higher continuity.

Things that are curvature continuous have some interesting properties when it comes to reflections - just tangent continuous things will cause a break in the reflection where it crosses the line between the 2 surfaces, while G2 continuous surfaces will have a smoother looking reflection line. So these things tend to come into play a lot more for objects that are highly reflective like car bodies.

- Michael

Thanks Michael. Not that I think I really understand!!
I my terms, I think you would be suggesting to try out those alternatives if all else fails?

There are a few other similar type things in the dropdowns that do not seem to be "detailed" in the Help.
Maybe some others may want to point them out.(If/when I know more I might better detail the questions!)

> I my terms, I think you would be suggesting to try out those alternatives if all else fails?

I guess the best way to sum it up would be to try those options if you want something that is less "mechanical" than a regular circular cross-section fillet.

The blend options can give a more "organic" type of rounded piece.

With the exact circular cross-section, the fillet itself tends to draw some attention to itself, I mean that it tends to be more recognizable as a mechanical rounded thing. The blending styles can help to make the blend appear more seamless between things, like they are more one continuous skin.

For example if you were working on a dinosaur and had a surface for the dinosaur's leg that you wanted to join with the dinosaur's body, and then wanted to round out the sharp edge between these 2 pieces, that's the kind of thing that you would want to use a blend for instead of a circular fillet, because dinosaurs don't have exact circle shapes in them.

- Michael

"because dinosaurs don't have exact circle shapes in them."

I will be giggling for hours Michael!

Anyway, thanks for that "witch" will be added to the previous in my Help!