FreeCAD Tutorial 0: The FreeCAD User Interface
Link to: CAD Main Page
Link to: Tutorial 1a (next)
Introduction
FreeCAD is a free, open-source CAD package that was under development for years; and recently it has produced a "release" version. By attracting developers from all over the design community, FreeCAD has assembled an impressive collection of features and add-ons.
Download FreeCAD
To get started, please visit the FreeCAD download site if you haven't already done so. When you click on the link it takes you to the FreeCAD download page.
Most of the FreeCAD user support is done through a Wiki. If you go to the installation instructions you will find more information on downloading and installing FreeCAD. This link also takes you to a large online user manual.
Load FreeCAD From the Desktop
Double-click on the 
FreeCAD icon (or shortcut) on the desktop. The window will show a startup dialog as shown below. Click on New File - Parametric Part to create a new part.
Windows Menu Bar
The FreeCAD interface for Windows includes a standard menu bar, and no doubt analogs are there in the other operating systems.
The "File" and "Edit" menus include the usual items as well as some CAD-specific utilities. Most importantly, under the "Edit" menu, there are "Cut" "Copy" and "Paste" what work as one might hope. In a sketch, the user can select one or several items, pull down "Copy" and the "Paste."
The effect is to copy the selected features into the clipboard and then paste the copies onto the same location where the originals were copied. To use this feature effectively, the original items must be moved away from their original location after "Copy" but before "Paste." Then with every subsequent "Paste" the user must move the new clones out of the pasting location and over to their intended destination.
Further down the Windows menu are items for "Sketch" and "Part Design" which are the most frequently used "Workbench" tools and they are the focus of Tutorial 1.
Most, if not all, of the tools in each of the two workbenches ("Sketch" and "Part Design") are accessible through the respective pull-down menus.
Workbenches and Tool Bars
FreeCAD divides up its many features into segments called "Workbenches." They are documented in Wiki format on the FreeCAD website. In the tutorials that follow, we will be concerned only with the Part Design and Sketcher workbenches. These are analogous to the "Features" and "Sketch" tabs in SolidWorks.
The normal practice of designing a part is to open a (
) sketch on some plane, sketch a closed figure on the plane, and then extrude it into a third dimension using either the (
) "Pad" tool or the (
) "Pocket" tool in the "Part Design" workbench.
When a particular workbench is active, no operations are possible outside it. A toolbar will be displayed characteristic of the workbench. Below is a view of the "Sketcher" toolbar.
There are no titles on the tool icons and more tools exist than can even be displayed in this form. This can be a little bit confusing at the start, but it saves a lot of real estate in the window. Throughout this tutorial, the icon for a tool will be displayed along with its name when it is mentioned. In some cases you will need to open a popup menu indicated by the (
) symbol
History List
The sequence of operations used to design a part are displayed in the "Part Design" workbench in a history list similar to that shown in SolidWorks.
You can edit features at any point in the list to change dimensions after they have been set. You need to be careful not to change parameters that may cause problem with design features further down the list.
Constraints and Elements Selection Lists
As you add features to a sketch, FreeCAD builds a pair of lists of references to the sketch elements and the constraints that determine their location and properties.
These lists get very long rather quickly, so they are difficult to use. When you click on a feature in the sketch, the corresponding element in the "Elements" list is highlighted. This is a little bit useful, but if you want to use the tool extensively, you will need to rename the features so they can be identified in the list box.
Dimensional constraints are treated like sketch elements in a parallel list. You can select and delete constraints if you need to, but finding the right one can be tricky. In the illustration below, the numeral "8" just below the left-center of the figure indicates that constraint number 8 applies to the horizontal alignment of the circle center point. If that constraint needs to be deleted, you need to find entry #8 on the "Constraints" list, select it, and hit the -DEL- key.
Items can be selected off of these lists and subjected to the "Cut" "Copy" and "Paste" operations either from the Windows "Edit" menu, or using the control characters -CTRL-X- ; -CTRL-C- ; and -CTRL-V- respectively.
FreeCAD is available on a variety of computer brands and operating systems, including Windows, MacOS, and Linux. For this tutorial, we focus on the PC interface which uses a three-button mouse.
On the PC, the LEFT mouse button is used for selection.
The MIDDLE button (actually a wheel) is used to move the part rendering around in the graphical space. The wheel functions as BOTH a button and a track-wheel, so there is a lot you can do with it.
If you spin the wheel, that causes the image to zoom in and out.
If you click down on the wheel and drag the mouse, this causes the image to pan around the window.
Rotating the image is done through the (
) orientation icon in the upper-right corner of the window. The faces of the solid are controls that deliver the orientation indicated. The arrow buttons in the margins cause the image to rotate by an increment.
