Panel and Standoffs
Our first enclosures won’t actually be fully enclosed. They will be comprised of two or more laser cut rigid panels (wood, acrylic, or mat board most likely), machine screws, and standoffs.
These are quick, forgiving enclosures that are a great choice for early prototypes.
Our CAD (Computer Aided Design or Drafting or Drawing) of choice will be VectorWorks. If you haven’t already, please download the free student version.
We will stick to 2D drawings for now in order to create 2.5D parts. Simple drawings can turn into involved parts.
We’ll go over the basics of creating drawings quickly so we can get to the laser. Demo will highlight combining simple geometry using the paint bucket tool, drawing placement, and exporting the file(s) correctly.
Download this template, open it in Vectorworks 2019, and save it as a default template.
The 2D Polygon Tool can make complicated geometry very quickly from simple shapes.
Export drawing to an EPS file that we can open in Adobe Illustrator.
Let’s take the following button as an example, Mini LED Arcade Button – 24mm Translucent Blue
First we get the datasheet.
We decide what is the hole size for the button.
And we note how deep the part will sit.
If we are happy with this part, we record the info (name, link, vendor) in our Bill of Materials (BOM).
We will create our basic enclosure shape and place our components in CAD.
Either read the datasheet or measure the components with digital calipers. Design holes from datasheet for buttons/switch holes
Add tolerance where needed. Remember, the laser is not really that accurate. More material can be removed if the material thickness is thin or if you run the laser hot.
Laser cut cardboard panels first.
Fasten standoffs and screws.
What is Tolerance?
Tolerance is an allowable amount of variation of a specified quantity, especially in the dimensions of a machine or part. Basically, it’s how much wiggle room should you give something. One of the keys to good making is knowing when to use tight or loose tolerances.
Laser Cutter Basics
The laser cutter is an incredibly useful tool that essentially works like a printer. Only this printer cuts and etches material.
Before you cut any of your “good material”, first prototype in cardboard. You will most likely see mistakes or make changes after your first cardboard enclosure comes together.
Counter Sink Screws and Drill Bits
If you want your screws flush with a panel’s surface, use counter sinks screws and drill bits.
Adding rubber feet on the bottom is always a nice touch.
Just a few minutes, using only the Tripoli Polishing Buffing Compound, leaves an amazing glass like finish. It also has the added benefit of softening all of the sharp edges of the acrylic.
Round your corners whenever possible. This eliminates sharp edges that can become damaged or cause injury (acrylic can cut skin, trust me).
As a rule of thumb, hole placement from the edge should be twice the material thickness.
Comparing Pictorial and Tangible Notations of Force Image Schemas and the accompanying video
Clocks are due next week.
Vectorworks tutorial (pdf)