I have used a number of CAD programs over the years. I started with a T-square and drafting table. I located some of my professional drawings a while ago.
At RPI, I learned Pro/Engineer. When I started my academic job, the university used Autocad. So, I’ve brushed into Mechanical Desktop and Inventor. The university switched to Solidworks some time ago.
Although Solidworks is a wonderful program, it is difficult to learn, and it is expensive. I made a series of training videos to be used with the Solid Modeling and Design class. We made a decision to use a local deployment of Vmware to support the class room activities; however, the support has been dismal and the hardware has never been capable of deploying all the features of Solidworks during a final week of term usage crunch. Additionally, student user files are routinely deleted (with no notice) as we change semesters.
We’ve ended up using the student edition of Solidworks and local deployment of the program to “solve” this problem. It begs the question, though, why invest in an expensive license and an expensive, complicated deployment solution that you don’t use!
So, I’m exploring Freecad and Librecad as alternatives to Solidworks in an academic environment. Can we do enough with these programs to manage our educational needs?
This blog is a notebook of my early experiences in learning the software for the purpose of modifying the Solid Modeling and Design tutorial videos.
Step 0. Download and install Freecad (see freecadweb.org). The version as of this writing is 0.18. The next version (0.19) will soon be deployed.
Step 1. Make a part in Freecad. See here for the Freecad wiki. This wiki gives a good basic introduction to making a part using Freecad.
- Maneuvering in Freecad:
- scroll wheel zooms in and out
- middle button + mouse movement pans
- shift+right click + mouse movement rotates the view
When you get started, there will be a ‘start page’ which is designed to help you. It will get very annoying when this page keeps popping up. At the bottom center, you will see the open pages. Click the x button next to ‘start page’ to get rid of this. When you have multiple pages open, you can select the active page by clicking on the tab in the bottom center.
Step 2. Freecad is built around workbenches, and developers are constantly making and obsoleting workbenches. The first obstacle I hit was how to make assemblies. The assembly workbench is not (yet) part of the default Freecad build. I’m trying a2plus (see tutorial) and assembly4 (see tutorial). However, the Freecad community is talking about how assembly functionality may be delayed until version 0.19. Workbenches are easily installed using the Tools -> Addon Manger menu item.
Step 3. STL and 3D printing integration. I have very briefly explored the ability for Freecad to import and export STL files. This looks promising.
Step 4. Engineering Drawings. TBD
Step 5. Parametric Design. TBD
Step 6. FEM integration. TBD I might accelerate this task due to my upcoming Mechanical Design class. I have tried to use the Solidworks workbench with Ansys. See above for my complaints about the maintenance and function of the Vmware facility by our ITS department.
Step 7. Mechanism integration. TBD
As an aside, when I decided to make training videos, I used The Dancing Robot platform to reveal a design and modeling approach in a step-by-step manner. Although off-the-shelf tutorials get the job done, having a project that steps students through the design (rather than how to use the software) has a much bigger impact on learning. A video tutorial is much easier to walk through than a written tutorial. Showing how the software works makes for a better learning environment than reading about how the software works.
I have also been working on a battery pack and case for the Beaglebone microcontroller. We are attempting to use only 3D printed parts for this project, so that it is very easy for a hobbyist user to create a fully functioning data acquisition system with telemetry. I plan to use this platform for another tutorial.
STL import tutorial (sort of): https://3dprinting.stackexchange.com/questions/6447/split-edit-part-in-freecad
Stuff about assemblies: https://forum.freecadweb.org/viewtopic.php?t=35542
NOTE: unlike other CAD programs I’ve worked with, Freecad has made a decision to keep the order in the “model tree” the chronological order. This means you need to plan ahead in making a part. I suspect this will be the art of making a part, rather than the skill of making a part.
NOTE: Freecad allows you to construct multiple bodies within the same project. Rather than maintaining separate files, you can create separate bodies. Set different colors on the different bodies. It will help you see the differences.
Select a body. go to View->Toggle Visibility to hide/show a body in a File.
