4. Modeling concept and basic manipulations

Simulation of TinkerCad program

To understand the simulation process, let’s try the open source virtual program TinkerCad. 

• Click on the link →https://www.tinkercad.com/dashboard. Clicking "Creat new design" prepares the desktop. 
• Drag the cube into the empty space from the toolbar on the right. On the left side of the window, the navigation tool (cube-shaped) must be set to “Front”.

^{Figure 22. Editing parameters of cube}

^{Figure 23. Scene view after grouping}

• To change the parameters of a cube, clicking on it opens a window with the parameters next to it (Figure 22). 
• The program allows you to choose from different types of shapes. Possible settings are a convex model or a recess (or hole) in its shape. 
• Select the sphere tool, load it in the top plane of the box, and set the hole parameter. This will give us a spherical recess in the cube.  
• Place two cylinders on the different edges of the box. Set the property to "solid" for one and "hole" for the other. The shapes assigned to the "hole" feature look like glass. But this is only an imaginary part of that figure. In order to "cut" holes in the box, all parts of the scene need to be grouped. 
• Select all objects in the scene and select the "group" function (Figure 23).
• All you have to do is export the prepared model to * .stl file (Figure 24). You can choose to print the entire model or specify specific parts. 
• There is also the option to save the model, or print directly. TinkerCad has the ability not only to print the model, but also to cut it with a laser  machine.  

^{Figure 24. Exporting a file}