Aim:

To design, prepare, and (optionally) print a small assistive tool such as a bottle grip, key holder, or switch extender.

Requirements:

• Computer with Blender

• Slicer software (e.g., Ultimaker Cura, PrusaSlicer, or Bambu Studio)

• Access to a 3D printer (optional but recommended)

• Filament material (PLA or PETG preferred for beginners)

Step-by-Step Process

Step 1: Identify the Purpose

Think about how 3D printing can help someone.
Choose a simple assistive tool idea such as:

• Bottle Grip: Makes opening bottles easier for people with weak grip.

• Key Holder: Helps elderly users turn keys comfortably.

• Switch Extender: Allows small children or wheelchair users to reach switches.

Ask yourself: Who am I helping? What problem am I solving?
This step builds empathy-based design thinking.

Step 2: Design in Blender

1. Open Blender and start a new project.

2. Use basic shapes — cylinder, cube, torus — to form your object.

3. Combine and modify shapes using:

   • Scale (S) to resize

   • Boolean Union to join parts

   • Boolean Difference to cut holes or grips

4. Check dimensions (use N → Item → Dimensions) to ensure realistic size (e.g., 8 cm long grip).

5. Save your Blender file (.blend).

Design Tip: Keep edges smooth and avoid too thin parts — thin areas can break during printing.

Step 3: Export as STL

Once your model looks ready:

• Go to File → Export → STL (.stl).

• Choose a name like bottle_grip_v1.stl.

• Save it in your project folder.

This file format captures only the surface geometry of your model, ready for slicing.

Step 4: Slice the Model

1. Open your slicer (e.g., Cura).

2. Import your .STL file.

3. Set the following parameters:

   • Layer Height: 0.2 mm (good balance between detail and speed)

   • Infill: 20–40% (determines strength)

   • Supports: Enable if your design has overhangs

   • Material: PLA

4. Click Preview to see how each layer will be printed.

You’ll see the model divided into hundreds of horizontal layers — this is how the printer builds your design.

Step 5: Generate G-code

• Click “Slice” → Export the G-code file to your SD card or USB.

• This file contains the movement commands for the printer nozzle.

Step 6: Print and Observe (if available)

• Insert the SD card into the 3D printer.

• Start the print and watch the first few layers to ensure adhesion.

• Once complete, carefully remove your model from the print bed.

Note: If a real printer isn’t available, students can use the 3D print preview in Cura to simulate printing and observe layer build-up.

Step 7: Evaluate the Design

• Does your printed object serve its purpose?

• Is it strong, comfortable, and useful?

• How can you improve the next version?

Write a short reflection:

“My design helps users by ________. If I redesigned it, I would ________.”