Fab-in-a-Box Invention Kits: Exposure

Before learners arrive, prepare a premade geometric invention kit using the xDesign template. Begin laser cutting the example kit just before the session starts so learners walk in to the sound and sight of the laser cutter in action. This creates immediate engagement and curiosity. Place a few completed kits on display at each table to spark conversation. Ensure each learner has access to a computer with xDesign loaded and the template file open. Have cardboard sheets ready at each workstation, and double-check that the laser cutter is calibrated and materials are safely staged.

Welcome:

Welcome learners to the session, and introduce the activity: adjusting a premade geometric invention kit using a parametric xDesign template. Explain that this lesson introduces foundational design concepts, such as symmetry, proportion, and kerf, the small amount of material removed by the laser cutter that affects how parts fit together. Briefly define CAD (Computer-Aided Design) as a tool used in engineering, architecture, and product design to create precise digital models. Emphasize that learners will be using CAD software to modify a design and then fabricate it using a laser cutter. Show a few completed invention kits and point out the one currently being cut to spark curiosity and discussion.

Context:

Rapid prototyping, press-fit slot-and-tab assemblies, parametric design:

In the real world, engineers and inventors often face tight deadlines for solving problems. It’s easy to get overwhelmed or to not know where to start! Invention kits can help facilitate brainstorming and accelerate the prototyping process. They provide a ready-made set of components that can be easily assembled and reconfigured to test out various design concepts.

LEGO bricks are a great example of an invention kit. They can be quickly assembled or disassembled in a variety of ways to illustrate a concept or test out an idea. Your invention kits will work similarly, allowing you to build upward but you get to customize the pieces!

Key terms:

Parametric Design: This design process uses parameters to define a model’s geometry. By adjusting these parameters, designers can easily modify and optimize their designs. This approach is particularly useful for creating customizable and scalable components in CAD software.

Kerf: This is the width of material removed by the laser cutter during the cutting process. Understanding kerf is crucial for ensuring that parts fit together correctly, as it affects the precision of the cuts and the final dimensions of the pieces.

Toolpath: This is the path that the laser cutter follows to cut or engrave the material. The toolpath is generated from the CAD design and dictates the movement of the laser, ensuring that the design is accurately

transferred to the material.

Start by opening the premade xDesign template on your computer. This file includes a basic geometric invention kit that you’ll customize by adjusting different parameters.

Begin by exploring the design:

Try changing the number of sides on the polygon.

Adjust the length, width, and placement of the slots.

Notice how these changes affect the overall shape and how the pieces might fit together.

As you work, think about how symmetry and proportion play a role in your design. You’ll also learn about kerf, which is the small amount of material removed by the laser cutter. This affects how tightly your pieces fit together.

Experiment with different combinations, and preview your changes in the model. You’re using CAD (Computer-Aided Design) software, which helps engineers and designers create precise digital models for real-world production.

Explore and adjust the template:

Open the premade xDesign template, and begin exploring the editable parameters. Try adjusting the number of sides on the polygon, and experiment with slot placement, length, and width.

Observe how changes affect fit and form:

As you make adjustments, notice how the shape changes and how the slots might affect how pieces connect. Think about symmetry and proportion, how do these design elements influence the overall structure?

Preview your design:

Use the preview feature in xDesign to see how your modified parts will look when cut. Consider how the kerf might affect the fit, especially if your slots are very narrow.

For xDesign Steps Click Here

xDesign steps can also be found:

In xDesign under Content

Laser cut the designed parts from cardboard sheets:

If using xDesign:

Click “fab connect.”

Open laser cutter lid, and place stock material onto honeycomb.

Click process.

If using XCS:

Import design file: Save your CAD file in SVG or DXF format. Then, import it into XCS. As long as it was created at a scale that can fit on the laser bed, it will open at actual size. You can double check by selecting the design and looking at the dimensions shown in the “size” boxes across the top of the screen.

Configure cut settings: Select the appropriate material from the menu on the right side of the screen. (Hint: “corrugated paper” = cardboard.)

Choose cut settings: Select all elements you want to cut and choose “cut” under “processing type” in the object setting menu on the right.

Optional: engraving – If there are any decorative elements you wish to engrave instead of cut, select them and choose “engrave” under “processing type” from the object setting menu on the right. They should fill in. Enter the appropriate settings for your chosen material.

Prepare laser cutter:

• Open laser cutter lid and place stock (balsa) onto honeycomb.
• Manually drag laser head over center of stock.
• Close lid.
• Click “auto focus,” and wait for machine to focus.
• Open lid. Manually drag laser head to top left corner of desired cutting area.
• To check framing, click “framing” in XCS, and then press the button on the machine. The laser head will frame the area to be cut. If it does not fit on the stock or overlaps a previous cut, adjust the starting position as needed.

Run job:

Click “process” in XCS, followed by the button on the machine.

Remove pieces:

Check to make sure all pieces cut through, and rerun if not (adjusting settings as necessary).

Remove workpieces and scrap stock from machine bed.

Close lid.

After the cutting is complete, carefully remove the shapes from the cutting bed. Clean off any debris or residue from the edges of the shapes.

Consider saving your excess material once you’ve punched everything out; this can be incorporated into your designs, too!

Now for the fun part: Build!

Use your construction kit to build something new! Make assemblies by slotting the shapes together to form three-dimensional structures. Experiment with different combinations of shapes to build various structures. Take note of any improvements or modifications that could enhance the kit’s usability, and consider iterating your designs accordingly.

Congratulations! You’ve successfully created your very own invention kit. Whether you’re using it for brainstorming, rapid prototyping, or unleashing your creativity, your kit is a versatile tool that empowers you to bring your ideas to life. Keep exploring and experimenting with your kit to unlock new possibilities and innovations!

Extensions:

3D print connectors

Incorporate flexures

Design and categorize multiple types of pieces:

Anatomical = heads, arms, legs, hands, feet, tails

Whimsical/decorative = wings, horns, accessories

Mechanical = wheels, gears

Structural = beams

Pose prompts to overcome “blank page syndrome” and encourage creative thinking. Ask learners to build a character, building, or prop and write a story that incorporates it (English), re-create a favorite landmark or design a new monument (civics/history), or design something with multiple degrees of symmetry (math/geometry).

Discussion Questions:

What design choices worked well in their invention kit?

How did kerf affect the fit of their pieces?

What would they change or try next time?

Optional Tie-ins:

Mathematics:

Geometry and Measurement: Integrate lessons on geometric shapes, angles, and measurements. Students can apply these concepts when designing their invention kits, ensuring accurate dimensions and fit for the slot-together pieces.

Algebra and Parametric Design: Use algebraic expressions to define parameters in CAD software. This helps students understand how changing variables can affect the overall design, making it easier to create scalable and customizable components.

Art and Design:

Graphic Design: Introduce basic graphic design principles, such as balance, contrast, and color theory. Learners can apply these principles to create visually appealing and functional invention kits.

Creative Expression: Encourage learners to express their creativity through their designs. They can incorporate personal themes, stories, or messages into their invention kits, making each project unique and meaningful.

Engineering and Technology:

Mechanical Engineering: Explore the engineering behind slot-together mechanisms. Discuss how different types of joints and connections can create stable and functional three-dimensional structures.

Technology Integration: Highlight the role of technology in modern design and manufacturing. Discuss how CAD software and laser cutters are used in various industries, from product design to architecture, and how these tools can streamline the prototyping process.

Career Connections:

Learning to design and fabricate invention kits using CAD software and a laser cutter opens up a variety of exciting career paths:

Mechanical Engineer: Mechanical engineers use CAD software to design and analyze mechanical systems. The skills learned in creating invention kits can be applied to prototyping and developing functional components, enhancing the ability to design efficient and innovative solutions.

Graphic Designer: Graphic designers can use CAD software to create precise and intricate designs. The experience of designing invention kits helps in understanding the principles of form and function, which are essential for creating visually appealing and effective designs.

Physicist: Physicists often need to create experimental setups and prototypes. Knowledge of CAD software and laser cutting can aid in designing and fabricating custom components for experiments, allowing for precise control and customization of experimental apparatus.

Marketer: In marketing, the ability to design and produce custom invention kits can be a valuable skill for creating engaging promotional materials and interactive products. These kits can be used to demonstrate product features, engage customers, and enhance brand experiences.

These career connections highlight the versatility and applicability of the skills learned in this lesson, showing how they can be valuable in various professional fields.