From the 4.0 version, CAD GRAAL offers for you to create 3D surface drawings. These functions will enable you to draw very varied shapes with great ease, notably by thermoforming stamping. Implementing these functions is extremely easy because it uses the 2D tools of the CAD software; only four icons have been added to generate surfaces.

Pentium II 233 Mhz 128 MO de RAM.

The general method for generating surfaces consists of the creation of "profiles" and possibly "guide curves", or closed contours that will be made in 2D with all the familiar tools, on which the surfaces will be based. In fact, the surfaces are generated automatically, and only the profiles, guide curves or contours are to be drawn in 2D.

N.B.: the term "guide curve" is a generic term; it is obvious that they can be created with all the types of entities available: (lines, polylines, Béziers curves and circles)

The "profile" will be used to create the surfaces, it is in fact the representation of a section of the surface thus generated.

Attention: the profiles, guide curves or contours must, if they have been constructed with several objects, be locked (sub-menu "lock" then the "edit" menu). The lock entirely links the entities together by transforming them into Béziers curves. Not to be confused with the " associate " function.

To create surfaces, it is sometimes necessary to direct the curves or profiles along the " Z " axis. The " 3D " icon   to be found on the horizontal bar will enable you to activate " Z " axis data entries and because of this create moves, rotations, etc on the different objects following the three axes. In " 3D " mode a rotation on the " Z " axis is made by using the " rotation " function of the contextual menu, by clicking on "show the centre or the rotation axis" then by designating two points on the " XY " view ; the object will be rotated by turning around this axis of the indicated angle.

Attention: in 3D mode, to make a rotation on the XY plane, just click the rotation point then validate with a right click (this " right click " validation is not necessary in 2D because only one rotation is possible).

Generally speaking, it is advisable when drawing in " 3D " to create several windows depending on the size of the screen, to have several different views, the ideal being to have the four views: XY, XZ, YZ, and perspectives. In fact, some manipulations and modifications are possible in all the planes. To have faster access to all the views, four icons have been added for calling up views directly, to avoid scrolling the " window "menu. Four types of surfaces can be created:

An extruded surface is a surface that is created by the movement of a profile following a straight line or a curve. The extrusion can be linear or based on a guide curve.

In the CAD module, click on "new file".

For this example, use the dimension parameters of the default blank.

Create a new window and arrange the screen as on the following view attributing the "perspective" view to the smallest window. Activate the "realistic rendering" on the
" XY " view.

to create a new window, just click in the window menu on "new window" then on " tile " and finally redimension the windows as in the example.

Draw a profile on the " XY " view (a semi-circle as in the example).

Activate the " 3D " functions   

Select the profile and make a rotation of 90° following the " Z " axis placing the rotation axis at the base of the arc.

The position and the length of the rotation axis are of no importance.

N.B.:

If you click from left to right the profile will be in positive.

If you click from right to left the profile will be in negative.

If the value is less than 90° it is the opposite.

The profile is now at 90° in relation to the " Z " axis.

N.B.: the rotations are always in the trigonometric direction (anti-clockwise)

Click on the icon: "surfaces"     then on the icon: "extruded surface" 

In the following window, validate: "linear" extrusion mode then click on " OK ".

Position the first point of the extrusion line (for example on the left side of the profile)

Click then position the second point at the desired final place of the extrusion.

Once the second point is validated, the surface is created, the "realistic rendering" function of the "window" menu creates this surface.

All the modifications: (formings, rotations, etc.) are possible on the object thus created; these modifications can also be created on the " XZ " and " YZ " views