CAD using LibreOffice Draw

[ You may also be interested in my Brief Overview of Free CAD Software. ]

Introduction

Let's be frank: The title of this page is a bit misleading, as LibreOffice Draw is not true CAD software. However, Draw is still very useful for a variety of technical and machine drawing tasks. Draw is often compared to Microsoft Visio, although it should be noted that it does not have all of the capabilities of Visio, and it cannot import or export Visio file formats.

Advantages of using Draw for technical drawings:

  • Free
  • Relatively easy to learn and use (compared to CAD)
  • Many powerful drawing features useful for technical drawings
  • Easily export drawings as PDF files to facilitate sharing
  • Easily export files in a variety of image formats
  • Easily incorporate charts, tables, spreadsheets, formulas, etc. from LibreOffice or other applications
  • Easily to add images to drawings
  • Word processing, spreadsheets, presentations, and database are included if you need any of these
  • Available for Linux, Macintosh, and Windows

Here's a link to a brief overview of LibreOffice Draw: https://www.libreoffice.org/features/draw/

See the Libreoffice adviser main page for more about LibreOffice and how to get it for free.

Disadvantages of using Draw for technical drawings:

  • Cannot import or export common CAD file formats (e.g., DXF, DWG)
    • Correction (9/5/2012) - import of DXF files is now possible, but not export
  • Limited set of shape libraries
  • Very limited 3D capabilities - essentially no 3D drawing capability (in the sense of 3D CAD)
  • Limited set of shapes ("CAD blocks") as compared to CAD

Notwithstanding the disadvantages listed above, Draw is still a very useful application for creating 2D technical drawings. The addition of some basic template shapes improves the utility of Draw for this purpose, and such a template is provided here specifically for machine drawing use.

The LibreOffice Draw template of machine drawing shapes is available here: ‎machine-drawing-symbols.odg

The shapes in the above file can be cut and pasted, re-sized, and combined in a variety of ways to provide basic shapes such as screws, nuts, bolts, washers, etc. commonly used in machine drawing.

See something missing you think should be there? Leave a comment below - any suggestions for improvement will be greatly appreciated.

‎If you just want to see what the file looks like, see this PDF version: machine-drawing-symbols.pdf

The above file is provided for convenience only; it will enable you to see what the template file looks like without having to download and install LibreOffice.

A Simple Drawing Example

The simple example below shows some of the fundamental capabilities of LibreOffice Draw, together with shapes taken from the machine drawing symbols file provided above. Of course, LibreOffice Draw has many more functions and capabilities than are shown here, and is capable of producing drawings of much greater complexity.

This example - a bracket for a shaft - is intended to serve only as a brief introduction.

Our simple example starts with some basic shapes. Basic shapes such as rectangles, squares, circles, triangles, etc. are built into Draw.

Basic shapes can be easily re-sized, filled in with colors, hatching, or gradient fills, and so on.

Shapes can be moved, "flipped", rotated, re-sized, and manipulated in a variety of ways. Here, we simply position the shapes next to each other in preparation for merging.



Shapes can be combined in a number of ways. Here, the two shapes are merged to create a new shape. Multiple individual shapes can also be "grouped" so that they can be handled as a unit.

Another basic shape (circle) is added. Note that shapes can be sized either manually (using the mouse), or by inputting specific dimensions.



Another basic shape (rectangle) is added.

The base is moved into the correct position (in this case, with the help of an automatic centering function). We show drilled holes in the bracket using rectangles with dotted line borders; we could also have just used two dotted lines. Lines can have different "weights" (thicknesses), colors, and styles (solid, dotted, dashed, etc.).


Here we see the machine drawing template in use. A machine screw is copied from the template, re-sized as needed for this drawing, and then copied again to provide the second screw.


We add hatching to the base (using an automatic "hatch fill") to make it distinct from the bracket. A variety of hatching styles are available, and custom hatching can also be created.

Dimension lines are a built in function; the line length is automatically filled in based on the drawing scale (or it can be manually entered). Call out lines are also built in, in a variety of styles.


3D shapes are possible, but are fairly limited. Still, it is possible to color 3D shapes, or even add surface texture, as well as to change lighting direction and intensity.

The LibreOffice Draw template of machine drawing shapes is available here: ‎machine-drawing-symbols.odg