When you import scan data, the data will be loading in the software, and a new Mesh Feature will be added in the Feature Tree. Sometimes, you can have additional items created after the Mesh Feature, but you will not be able to immediately be able to trim the mesh using these items. This is because parametric CAD systems have a history, meaning that it not only records what you do, but when you did them, and what the current state of the model was at that time. When we Rollback to edit the model, we are going back in time. Any items that did not exist at that time will not be available. We have three possible solutions to this situation, as follows:

Preparation
1. Click the (Import) button, Click Insert > Import to open the Import dialog box.
2. Select all files.

3. You can see an unedited mesh data as shown in the image below.

1. Using Ref.Plane

First at all, when you create a Ref. plane, the plane feature is recorded under the mesh feature. In this case, you will not be able to select of use the Ref. plane. We can, however, chage the order of the events in our history. By moving the plane to occur before the mesh, we will the be able to use it while editing our mesh feature.

You must move the Plane 1 up before the mesh feature, as shown in the image below.

Double click the Mesh Feature in the Feature Tree or click the (Mesh) button. You will enter the Mesh mode, and then you can edit the mesh by using the Ref. plane.
You can see the Ref. Plane in the Mesh mode as shown in the below image.

Click the (Split) button, or click Tools > Mesh Tools >Split in the menu.

Check By Entity as Method and select Plane1 as the Tool Entity. If you want a closed mesh, you can check the Cap Section Ends option. Click the (Next) button.

Select the remaining region and click the (OK) button.
Shown below is a split mesh.

2. Using a 3D Sketch

This method is to use the 3D Mesh Sketch. First at all, you must sketch a line by using the spline command, and then copy and to move it.

Click the (3D Mesh Sketch) button. Click the (Spline) button, or click Tools > 3D Sketch Entities > Spline in the menu.

Sketch the spline on the mesh as shown in the image below.

Click the (OK) button. You can see 3D Sketch 1 Feature located under the Mesh Trim Feature. In this case, you cannot edit the mesh with the 3D Sketch.

Select 3D Sketch 1 in the Feature Tree and copy it using Ctrl + C on the keyboard.

Click the Ok button.

To paste the Copied Sketch (Ctrl + V)

Select Copied Sketch and move it up before the mesh feature as shown in the image below.

Double Click the mesh and enter the Mesh mode.

Click the (Trim) button and check By Curve as the Method. Select the previously created spline as the Curves. Click the (Next) button.

Select the Remaining region and Click the (OK) button.

Shown below is a Trimmed mesh

3. Moving the mesh

This method is to use the copy & paste command and is very similar the previous method.

Click the (3D Mesh Sketch) button. Click the (Spline) button, or click Tools > 3D Sketch Entities > Spline in the menu. Sketch the spline on the mesh as shown in the image below. Click the (3D Mesh Sketch) button again to escape this mode.

Select the mesh in the Feature Tree and copy it using Ctrl+C on the keyboard.
Click the OK button.

Paste the Copied Sketch (Ctrl +V) and it is automatically placed at the end of the Feature Tree as shown in the image below.

Note

If the mesh is not placed in the appropriate place, under the 3D Sketch; you must click-and-drag to move the mesh feature below the sketch feature desired.

Double click the Copied Mesh to enter the mesh edit mode.

Click the (Trim) button and check By Curve as the Method. Select the created spline as the Curves. Click the (Next) button.

Select the remaining region and Click the (OK) button.

Shown below is a trimmed mesh.