Creates a circular fillet or a blending surface along selected edges of a given surface.
How to use
Round can be used in various situations and with different approaches. Let's examine some of them with the help of examples.
Rounding edges of a primitive
1. Click the Round icon or choose the Tools > Surfaces > Round command.
2. At the Tolerance console prompt, type the tolerance value for the Boundary Representation construction. Accept the default value (modeling tolerance of solidThinking).
3. At the Sew tolerance console prompt, accept the default value of the sew tolerance value for the Boundary Representation construction.
4. The program console prompts Pick a surface.
5. Pick the object whose edge/edges you want to round.
6. The program console prompts Pick edges.
7. Pick the edges you want to round directly in the views. To select multiple edges, just pick them while holding the Ctrl key down. Picked edges are displayed in yellow. See the following.
8. To end edge selection, press Spacebar.
9. The program console prompts Radius.
10. Type the radius value in the console. Default is 1.
Selected edge is now round.
Below you find an other example of filleting.
Creating a fillet between two given surfaces
We want to create a fillet between the cylinder and the parallelepiped.
1. Round works on one or more edges belonging to the same surface. Since Round does not compute intersections, you must first use the Intersect Modeling Tool in order to find them. After picking the two intersecting surfaces, the Console prompts Store each face as a separate object? and offers you two options: Y for Yes, N for No.
2. Type N if you want for the splitting of the intersecting surfaces to output a single object composed by all the resulting faces. This is often the most correct approach as it offers the possibility to maintain the model as a whole and, at the same time, to clear it of unwanted faces.
3. Click all the internal faces that would disturb edges definition while holding down the Alt key down.
4. Then use the Edit > Delete command or the Win / Mac shortcut to delete the picked faces.
At this point you are ready to use Round.
5. Click the Round icon or choose the Tools > Surfaces > Round command.
6. Then, pick the surface resulting from the Intersect Modeling Tool when the program console prompts Pick a surface.
7. At the Pick edges program console prompt, pick the edges you want to round directly in the views. You should remember that, dealing with surfaces and not solids, the only difference between round and fillet is the face you are looking at. In fact, seen from the opposite face, a round is a fillet, and viceversa.
8. To end edge selection, press Spacebar.
9. At the Radius console prompt, type the radius value in the console
A circular fillet has been created
Let's now go back to step 2, and examine the case where you type Y at the Store each face as a separate object? console prompt. Here, you are asking for the splitting of the intersecting surfaces to output separate objects for any resulting face.
This sort of approach can be practical when selecting and deleting internal faces of a model would otherwise be difficult. Thus, instead of deleting unwanted faces, you just select the ones pertaining to the round action or all the face that you want to keep.
Then you can use the Combine modeling tool to turn the faces you want to keep into a single object. As you can see in the wireframe picture below, only the internal face that was not selected has been left out the newly combined object.
At this point you can follow steps 5 to 9 again to obtain exactly the same result but through a different approach.
Troubleshooting
If you
need to round more edges of the same object, it is always suggested that
you perform this in the same operation (multiple edge selection is possible
when you pick them while holding the Ctrl
key down) instead of performing more round operations.
In
some cases one of the two faces which define an edge could be the result
of a fillpath command applied to a non-weighted circle. In this situation
you may have some sewing problems. Therefore you can raise the Sew tolerance
value since the beginning.
The constant radius round is based on rolling
ball method: a theoretical sphere of constant radius is rolled along two
boundary surfaces of selected edge. Points where the ball touches the
surfaces define the rails, then radius control the angle between surfaces.
If Round command fails you can try to change the Round tolerance. The suggested tolerance is a value that is 4 to 6 decimal places in accuracy relative to the size of the model. If the above operation fails, the problem could be due to edge gaps. Raise Sew tolerance by multiplying it for 10 and, if this is not enough, multiply another time for 10. Be careful not to use a Sew tolerance value much higher than Round tolerance in order not to slow down the program.
Round status
Round is currently supported for manifold edges. Manifold edges are edges with only two adjacent faces.
There are some cases, related to Round corners (what happens at the end of fillet surfaces), where round fails. In particular, case that have not yet been implemented are:
The edge to be
rounded is a closed edge (i.e. top edge of a cylinder) that attaches to
the vertex two times. It can have either zero or one additional edges
coming into the vertex. Start
and end of closed edge are not tangent (end of a solid created from extrusion
of a tear drop shape).
There are four or more edges adjacent to a vertex and not all of them (for example only two) need to be filleted.