DigiKey - Introduction to FreeCAD Part 6: Revolutions, Pipes, and Lofts | DigiKey
The video explores advanced 3D modeling techniques to create complex shapes, focusing on tools such as revolutions, pipes, and lofts. Initially, the video explains the use of the revolution tool to create symmetrical shapes by revolving a sketch around an axis, which can save time in designs involving circular features. The process involves creating a sketch, setting constraints, and using a data line for precise control over the revolution axis.
The video then transitions to designing a custom keycap for a mechanical keyboard, using the pipe tool to create a rounded shell and the loft tool to design the top. The pipe tool allows for creating complex paths and shapes by sweeping a profile along a path, while the loft tool enables the creation of smooth, organic surfaces by interpolating between multiple sketches. The video also covers the use of the groove tool for subtractive modeling and demonstrates how to add structural support to the keycap design. Finally, the video provides a practical demonstration of preparing the design for 3D printing, including generating support structures and slicing the model for printing.
Key Points:
- Use the revolution tool to create symmetrical shapes by revolving sketches around an axis, saving time on circular designs.
- The pipe tool allows for creating complex paths and shapes by sweeping a profile along a path, ideal for rounded surfaces.
- The loft tool enables smooth, organic surfaces by interpolating between multiple sketches, useful for custom designs.
- Structural support can be added to 3D models using ribbing techniques to enhance durability, especially for small parts.
- Prepare 3D models for printing by generating support structures and slicing the model, considering support type for ease of removal.
Details:
1. 🔧 Designing Advanced Shapes with Revolutions & Pipes
1.1. Revolutions for Complex Shapes
1.2. Pipes for Versatile Designs
1.3. Lofts for Organic Designs
2. 🖱️ Creating a Custom Mechanical Keyboard Keycap
- Ensure the keycap dimensions are compatible with Cherry MX switches, considering the slant and symmetry requirements for different rows.
- The stem height should be 1 mm from the bottom of the cap for accurate fitment.
- Utilize a multi-tool, like the polyline tool, for sketching on the XZ plane, although initial line creation may encounter a bug.
- Define and adjust constraints such as horizontal and vertical lines to achieve desired shapes, removing redundant or incorrect constraints as needed.
- Set specific dimensions: a vertical length of 10 mm and an underside thickness of 2 mm. Modify as necessary based on experimentation.
- Position key points and dimensions precisely, such as making a key point 25 mm from the center of arcs and 9 mm from the origin.
- Experiment with values to achieve the desired design, ensuring limited degrees of freedom in the final design.
3. 🐍 Using Pipes for Keycap Design
- The design process begins with an initial setup that includes defining a path on the XY plane to create a complex path using the pipe tool.
- Design precision is achieved using rounded rectangles with coincident and symmetrical constraints, and fillets set to 1 mm for structural integrity.
- Parametric naming of constraints, such as 'height' and 'top thickness,' facilitates easy adjustments and fine-tuning of design dimensions.
- Selecting sketches in the correct order is critical: start with the cross-section sketch, followed by the sweep path, and then choose the additive pipe for effective design execution.
- Completing the top of the keycap involves using the pad tool, adjusted to 'top thickness' for a perfect fit, ensuring a seamless design transition.
4. 🔄 Crafting the Keycap Stem
- The horizontal distance between two lines is precisely set to 3 mm, a decision informed by previous failed prints, ensuring a snug fit.
- Vertical distance is optimized at 1.61 mm, a critical measure to enhance the stability and fit of the design.
- The keycap stem's height is determined to be 4.4 mm, offering sufficient coverage over the switch.
- Fillets have a 1 mm radius, which not only strengthens the stem but also adds to its aesthetic appeal.
- Horizontal distance is further specified at 805 mm, derived from experimental data to refine the design.
- Vertical spacing between lines is adjusted to 2.2 mm, contributing to the keycap's structural integrity.
- Symmetrical constraints are employed to maintain design balance and uniformity.
- Equality constraints ensure that parallel lines are of equal length, contributing to the design's precision.
- The horizontal distance from the origin to a key point is termed 'half width,' simplifying reference and adjustments.
- A parametric gap of 1 mm is introduced, crucial for ensuring proper function and alignment of the keycap on the switch.
5. 🌀 Exploring Subtractive Pipes with the Groove Tool
5.1. Creating a Subtractive Pipe
5.2. Using Rounded Rectangles and Fillets
5.3. Adjusting and Deleting Sketches
6. 🏗️ Reinforcing Keycap Structure with Ribs
- The addition of ribs to the keycap structure helps enhance durability, especially for 3D printed components, which are prone to breaking due to their small size.
- Creating a brace structure or ribbing within the keycap significantly strengthens the structure, ensuring better performance and longevity.
- The ribbing process involves using a basic rectangle design, utilizing constraints like the coincident constraint tool to align and attach the ribbing accurately.
- Dimensioning the rib to 3.5 mm height, based on testing, ensures compatibility with keycap stems.
- A symmetric padding approach with a dimension of 2 mm is used to form the rib, providing a balanced reinforcement.
- The use of a polar pattern tool facilitates the creation of ribs around the keycap, addressing issues where ribs do not extend fully to desired points.
- The parametric nature of the design allows for easy adjustments, such as deleting constraints and making ribs coincident with lines, ensuring the ribbing is connected with no gaps.
7. 🌟 Designing a Teardrop Loft for Keycap Top
7.1. Creating Initial Teardrop Sketch
7.2. Copying and Modifying Sketches
7.3. Creating Multiple Sketch Layers
7.4. Using Loft Tool for 3D Shape
7.5. Finalizing the Design with Polar Pattern
8. 🖨️ Preparing and Printing the Custom Keycap
8.1. Preparation of the Custom Keycap
8.2. Printing the Custom Keycap
9. 🎨 Customization Challenge & Next Steps
- Participants are encouraged to create their own keycap or a custom knob for a household appliance.
- Designs should be shared on social media platforms like X, Instagram, or LinkedIn with the hashtag #dkfpread and tag Digi-Key.
- The next session will cover advanced features for creating organic curved surfaces.