In this chapter, all the utility functions currently available in the TOP package are presented.

First of all, it should be noted that these utilities are not intended only for mechanical designers, but for anyone who needs additional support in drawing. These functions therefore complement all the features provided by the base CAD system.

Some of these utilities are entirely new compared to traditional commands, while others are adaptations of existing ones, suitably modified. The result is a package optimized for both performance and functionality.

Construction Lines and Circles

These functions allow the drawing of horizontal, vertical, tangent lines, concentric circles, tangent circles, etc., using a special linetype. They provide useful references within the drawing.

These lines and circles can be hidden, deleted, or restored using dedicated commands. They are not intended to be displayed in the final drawing or printed—their sole purpose is to serve as precise references for the designer.

Fillets and Chamfers

The Fillet and Chamfer functions complement the base CAD commands, introducing small but significant differences.

For example:

  • It is possible to create a fillet or chamfer without modifying the second selected line
  • The two lines involved can be connected by thin continuous lines (useful as a reference for dimensioning the fillet)
  • It is possible to chamfer two lines by specifying only the distance on the first line and the chamfer angle

Special Modify

The commands described in the Special Modify section are essentially shortcuts that combine two operations into one.

They allow you to:

  • Move and rotate a selection
  • Rotate and then move a selection
  • Copy and rotate a selection
  • Rotate and then copy a selection

This makes it possible to select objects once and use a single command instead of two, improving workflow efficiency.

Text

Additional utility functions are related to Special Text.

These allow the insertion of text using predefined settings stored in the customization file, where both a Normal and a Highlighted text style are defined with specific color, style, and height.

Welding

These functions are specifically designed for mechanical designers.

They allow the creation of linear welds, circular welds, or welding triangles using settings defined in the customization file (which can be easily modified through a dialog box).

Machining Symbols and Surface Roughness

These functions enable the insertion of commonly used symbols to indicate the machining requirements or surface roughness of a component.

Mechanical Drawing

Also specifically designed for mechanical designers, these functions allow you to:

  • Draw shafts with varying lengths and diameters
  • Create shaft breaks
  • Draw section axes with references on any part
  • Add keyways for shafts and hubs
  • Draw splined shafts, spacers, and break lines (via a customizable library)

These tools provide effective support for creating precise mechanical drawings quickly.

Transmissions

A set of useful functions is also provided for calculating and designing transmissions, both chain-driven and belt-driven.

These functions guide the user step by step, from drawing sprockets or pulleys, to selecting the chain or belt, and finally adapting and drawing the transmission path.

Dimensioning

More general-purpose functions are available for dimensioning.

These include:

  • Adding dimensions to holes with diameter or threaded symbols
  • Dimensioning multiple selected holes relative to a reference point
  • Exporting measurements into tables

Tolerances

Commands related to tolerances allow the insertion of tolerance values and symbols in dimensions and text, including special symbols for geometric tolerances.

Special Functions

Finally, a set of Special functions is provided for optimized drawing management.

These include features such as:

  • Magnifying glass (zoom tool)
  • Block preview before insertion
  • Measurement of lengths and angles
  • And more

For better understanding, the following sections list and explain each command associated with these utilities.