Surface based features

Surface based features toolbar

Making a part solely with the part design workbench may not be possible. Therefore, at times, it may be required to use surfaces and we may create them in the Surface design workbench. The surfaces we create are put to use with the help of tools available in the surface based features toolbar. The surface based features toolbar comprises of tools like Split, Thick surface, Sew surface and Close surface. Let's see each none of them in detail.

Split - Split is used to cut part with the use of a surface. When the surface is used to cut the part, only one side of it can be kept and this is specified with the arrow direction (in orange).

Split performed using yellow surface as splitting element. Orange arrow direction can be changed with a click.
After the split, the surface was hid using the Hide/Show option.

After the split operation, the other half is removed. With the help of direction, you can specify which part you wish to keep. The Split would also work if you specify a plane like xy, yz and zx as Splitting element instead of surface. So you may cut your part even with a planar surface or a plane itself.

Thick surface - A complex feature of a part, or a complete part may be modeled using only surfaces. However, surfaces are of zero thickness and do not exist in real life. So, to convert it into a solid part that can be used for manufacturing of moulds etc, we would require to convert the surface into a solid part first.

Surface created a surfacing workbench, subsequently converted into solid by adding thickness of 2mm (1mm on each side)

Thick surface is one such command that can be used to convert a surface into solid. It adds thickness as per our desire and convert the surface into a solid.

Surface with open ends, closed to form solid

Close surface - A close surface tool can be used to convert a complex surface with open ends into a solid. A thing to keep in mind while converting such as surface is that the surface can be as complex as you want. However, the ends (as can be seen above) should be planar. If the circular ends of the cylinders were not planar, the close surface command would not have worked. Or you can use a completely close surface as shown below to convert it into solid (as seen below).

Closed surface, converted to solid.

Sew surface - With the use of sew surface, you can sew a surface to a solid and can combine them both into a solid body, a sort of boolean operation. The option would work only if the surface boundary lies entirely on the solid. Below you can see that we can combining a surface (yellow) with a body (green) and subsequently, you can see the resulting complete body (in green) after the surface is hid.

Where do we use sew surface?

Now one might think that where might this be useful. In case of a complex object that's being reverse engineered, many times could data of points is extracted using a CMM (coordinate measuring machine) and a surface is created fitting this cloud of points. Now this surface extracted may require to be combined with a solid base to make a mold or pattern, In such a case we may use sew surface operation. We may also use it to combine a solid with complex surface that we have modeled in surface design since it could not be created in a part design workbench.