- Here I want to talk boundary and extract.
You can either use the reference file that you downloaded,
or select on the extract function,
hit F1 on the keyboard,
download the file there, and get to work.
So here we have a curve and a solid
and you can do this on surfaces as well.
With the extract definition,
you're going to select either a face, an edge, or a vertex
that you want to extract.
So in this case, if I come to the solid,
I can specify this face and what it'll do,
let me select OK, is that it'll extract just that face.
It creates a surface based off of the face.
If I come in and I'm going to go into Part Design.
I'm going to throw an edge fillet on this.
Right here.
(mouse clicking)
Go ahead and hide this extraction.
I'm going to back into Generative Shape [Design].
Go to My Extract Tool.
Now I'm going to pick this face.
You'll notice that I have a propagation types as,
is set to no propagation.
If I change this to say tangent continuity,
what's going to happen is all those tangent faces
are going to come in and get picked.
Remember: the edge fillets will always create tangent
boundaries to the adjacent faces.
So there I have my extracted face.
Extractions are good for various reasons.
You may need to use that face over
and over again, and by extracting it,
you have now an element in the tree
that allows you to pick a stable element.
So if I need to reference it over and over again,
I just go back to the extraction.
Here you see I have a curve.
The same thing can be had, I can go into My Extract.
I'm going to pick this curve.
You'll notice that it picks most
of the curve and it stops at this point.
There's a slight discontinuity;
it tells you there's a discontinuity,
it's not tangent, at that point.
If I change this to curvature,
you'll notice it stops over here.
Because there's a difference in tangency to curvature.
If I wanted the entire curve to be extracted,
I could just change this to point continuity.
Select OK.
So using those different propagation types
allows you to be very specific about a region
or a portion of an element that you want to extract.
Go ahead and hide these extractions.
(mouse clicking)
Now...
Where does...
Boundary come in handy?
Boundary, again, is similar to the extract in that
it's going to, basically, pull off an element
and it's going to be a boundary type element.
If I come in here and pick this face,
it's not going to extract the face,
it's going to extract all of the boundaries
or edges of that face.
So I select OK, you'll notice it puts
that curve in the tree as a boundary.
And again, if I need to, let's say,
set put a points set along that edge,
rather than picking all of those edges,
I may just extract boundary, create the boundary,
put the points on that boundary.
That way if I need to make a modification,
the points will go with that boundary.
So if something happens I can always re-attach the boundary.
These are tools that help you in the modeling process.
We try to avoid picking edges and faces,
repeatedly, over and over again.
And this is kind of what these tools are for.
To give you the ability to create
a stable feature or an element in the tree.
If I were to use a boundary on this curve,
you'll see that it doesn't pick anything.
Because the curve in and of itself is a boundary.
Also if I try picking an edge, off of that solid,
technically, that is not a boundary, right?
That is an internal patch.
I'm going to cancel.
If I needed to get that internal edge,
I would go back and use the extract.
It's just saying propagation type is set to point.
Doesn't know what to do.
So I can just come over here and change it to no propagation
or tangent [continuity], select OK.
And now I have that boundary that is, or that, extraction
pulled off of the solid, from that edge as a reference.
Between the boundary and the extract,
you can build stable elements for re-use.
If I were to bring up this extracted surface...
There we go.
Let me go ahead and hide this solid.
Now, with the boundary...
Go in here, select My Boundary.
Pick this edge, you'll see right ow it's point,
it's going around all the way around the part.
I can come in here and say tangent,
it's going to just pick the tangencies and so on.
So, boundary is more for picking edges off of faces,
whereas extract, you can extract the entire face,
you can extract a region or a portion of a curve,
or even, with the extraction, you can extract out a vertex.
So if you know you need to use a vertex over and over again,
you can pick that vertex, select OK,
and it creates a point at the vertex for you.