Customizing Sick of Beige cases for laser cutting

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Contents

Overview

SoB LC OverviewTUT.jpg

Laser cut acrylic cases are super popular because they look cool, they're easy to customize, and cheap to make. Not everyone has a laser cutter, but there's cheap online services and your local hackerspace might have one.

This tutorial shows how customize our simple Sick of Beige cases to fit your own project. If you start with our standard PCB templates you can get your project into a case with minimal hassle.

Before you start

You'll need to have Google SketchUp installed. See our introduction to SketchUp.

Download and install the SVG export plugin

We'll use Seeed Studio's laser cutting service, they take SVG formatted files. Grab the SVG plugin for SketchUp to save in this format. Put it in the SketchUp plugins directory.

Download the case template

Download the SketchUp files that fit the standard size board you used.

You didn't use a standard PCB template? It's gonna be a little more work, but you can still follow along.

Position the PCB footprint at Eagle coordinate center

SoB LC TUT coorC.jpg

Open the PCB file in Eagle, and the case template in SketchUp .

The origin marker of the standard size PCB footprint in Eagle should be positioned at the Eagle coordinate center. Origin markers are something every Eagle footprint has, it is identifiable as a white + marker.

We positioned our SketchUp Template so the coordinate centers in Eagle and SketchUp match. Any location on the board relative to the Eagle coordinate center is mirrored to a location on the case template in SkectchUp relative to it's coordinate center (the intersection of Red, Green, and Blue guidelines)


Adding hole shapes for extruding parts

Find the part's origin point location relative to the coordinate center

SoB LC TUT grid.jpg

In this step we will find the location of the origins of various parts you want to cut holes in the case for. Keep in mind that the part's origin coordinates in Eagle are relative to Eagle's coordinate center.

First change the grid in Eagle to millimeters, found in the 'View/Grid' menu.

SoB LC TUT relcc.jpg

  • Right click on the component and select 'properties'
  • The 'Position' attribute is the origin's location
  • We will use these values to design the holes in SketchUp
  • The left panel is the X-axis, while the right is the Y-axis.

Using guide lines in SketchUp

SoB LC TUT guidce21.jpg

Once you have the location of the component draw guide lines in SketchUp.

  1. For X-axis click on the 'Tape Measure tool'
  2. Click on any point on the 'Green' coordinate line
  3. Drag the guideline to any point on the template and left click on that point

SoB LC TUT guide2.jpg

Now we'll precisely position the guideline to match the X-coordinate in Eagle, using the keyboard input method..

  1. Right after you click on the point, type in the numbers of the X coordinate
  2. For example, if the location is 51.5mm from the coordinate center in the X axis, just type in '51.5' and hit 'Enter'
  3. The guideline will be positioned at exactly 51.5mm

SoB LC TUT guide3.jpg

Once you're done with the X-axis guideline it's time to draw the Y-axis guideline as well.

  1. Repeat the above for the Y-axis only now using a point on the 'RED' axis line as the starting point
  2. Now you have guidelines pinpointing the exact location of the components center on the template.

Draw the hole shape for the part

SoB LC TUT hole.jpg

Once you have the part's origin location on your template, simply draw the outline of the hole you want to cut out.

Draw additional guidelines as needed, and refer to the component's datasheet for precise dimensions. Be sure to leave 0.5-1m of clearance for manufacturing defects.

Repeat for all extruding parts

Repeat the above for all the holes you'd like to cut out on your case. We use the 'Tape Measure tool' (guidelines) often. It simplifies the sketching, and allows you to control the location, and dimension of the lines exactly.

They are really easy to use, and after a couple of minutes you'll get the hang of them. Here is a manual for the 'Tape Measure tool' if you need some more help.

Export the shape to the SVG file

SoB LC TUT expSVG1.jpg

Simply double click on the template. All the lines on the template, and the face surface should be highlighted. Now right click on any highlighted area, and select 'Export to SVG file'.

SoB LC TUT expSVG3.jpg

The Export Plugin menu will open up. Fill it in as shown above, with the exception of the Output file pane, where you should enter the filename you want it to export to.

Once you've set all the options up, simply click 'Ok'. The plugin will let you know the file has been exported and you are finished.

Send for Laser Cutting at Seeed

There's several online laser cutting services. Some have an online interface for ordering, others need time to prepare a quote.

We send our designs to Seeed's cheap Laser cutting service. You can find further instructions at Seeed's laser cutting service page, but this is roughly what's involved:

Select the quantity, material, and the dimension options that suit your project.

For job difficulty, you need to estimate the overall length of the laser cutting lines. These include the template lines, as well as the hole lines. You can get specific parameters from SketchUp:

  1. Double click on the model
  2. Hold shift and click once over the highlighted area to deselect it, while keeping all the lines selected
  3. Right-click on any highlighted line and select 'Entity info'

Under 'Length' is the over all laser cutting length. If it's below 600mm your job difficulty is Easy, if it's between 600mm and 1800mm it's Normal, and anything over 1800mm is Hard.

Once you buy the cuts you will receive a order number. Compress your SVG file into an archive called L<order number>.rar (e.g. L123456.rar) and email it to Seeed.

Feel free to ask for help

Stuck on something? Ask us in the forum.

Share your designs

Case templates are open source and licensed under Creative Commons 0. They are free to use in any way you like, including commercial projects.

If you make something new please share your designs with us in the forum.