Home About Me Final Project Weekly Progress Notes
fab-academy2.jpg

[02/11/2014]

Week 2: Computer Aided Design

This week was playing around with different drawing and CAD programs to model the final project.

I chose to use 123D Design in the 3D modeling since it is designed as an entry level 3D modeling and since this is my first experience in 3D modeling I thought it would be easier to start with a simple software without all features found in the professional modeling software commercially available as Rhino and SolidWorks. Also I want to know early enough in the corse whether 123D Design would be a good choice for young makers to start with and what is the Pros and Cons between it and the other CAD software like Inventor and SolidWorks.

My First Attempts

I started by downloading 123D Design and going through some tutorials I found on YouTube you can find some links to tutorials I found of benefit to me.

After viewing the tutorials and playing around with the main drawing tools I decided to start with a pencil drawing sketch of what I have in mind as a rough design to my speaker and then draw that on 123D design.

123d_scrn1.png
First Attempt

However; I faced the problem of converting my model design in 123D design. I realized that CAD is something different than the drawing I used to know using graphic design Software.





Tools Used

123D Design
Inkscape

Tutorials Used

Getting Started with 123D
2D sketches with 123D
Sweep, Revolve, Loft with 123D
Complete CAD assembly with 123D

Think CAD

Designing for fabrication is another story than graphic design.  You need to think in parts, material specifications, and how parts are related. Measurements are another critical thing.

So after going through my first attempt; drawing my model with the outer appearance only in mind I found out that going from outer appearance to inner details is as doing it all over again. CAD software is built with the concept of bottom up design approach rather than top down design approach. In other words you sketch parts then start thinking of joining them to build the objects.

So I started again on paper breaking my design in parts, measurements and relations. Then moving to 123D design and sketching parts and finally assembling them.



sketch_prts.jpg cardboard_design.jpg
Design on paper
  
123d_scrn6.png 123d_scrn7.png
   2D sketch on 123D
123d_scrn11.png 123d_scrn12.png
Assembly & Rendering

When to use 123D  and When Not?

During the week I took a Jump Start session on AutoDesk Inventor with Aser Nabil our FabLab Guru J. It was a good session to help me compare 123D with Inventor and know more about the CAD world.

I consider 123D to be a user friendly software that you could learn most or all the features over 1 or 2 day playing around.

It is an excellent choice if the project you are attempting to design doesn’t consist of many interrelated parts since 123D doesn’t have parametric design features and also has only a simple snap tool for building your different assemblies that compose your model.  This comparison is based on my quick session on Inventor were I realized that Inventor divides the project into a project file with components that contains different parts and finally assembly files with more advanced features and options to define how parts are joined and related but of course with a more complex interface that could be a frustration for newbies and young makers.

One of the things that I figured out late is that the 2D export feature is not available except in the premium version.

I had a chance also to have a quick look at TinkerCad and I see that it is worth trying later since it has a parametric design utility using JavaScript as its back end; however, I couldn’t make a clear comparison with 123D other designing tools and features.

2D Vector Design:

For the 2D vector design I downloaded Inkscape and tried to import a line art bitmap that I thought it could one of the options for the shape of the speaker. I did a trace bitmap to convert it into vector design.

inkscape_scr1.png

Raster Design:

Since last week I used GIMP for bitmap resizing, scaling and compression while building this website. Also all screenshots for this week assignment was edited using GIMP.  I can say that GIMP is a really great opensource software that could be compared to PhotoShop.