3D Printing and Sacnning

In this page there is a link for the week 5 group assigment which is on 3D printing and scanning. The purpose was to test the design rules for the 3D printers we have. I have made a dsign rules for printer in the lab.
Group assigment
Individual Assignment

Design and 3D print an object (small, few cm3, limited by printer time) that could not be easily made subtractively

Matrix Lattice Design and 3D Printing Using FreeCAD

In this section, I present how I used FreeCAD to design a customizable lattice matrix structure suitable for 3D printing. The aim was to explore how to make object that is not easy to make subtractively.

I began the design process in FreeCAD by selecting the Part Design Workbench. Here’s the step-by-step breakdown:

• Step 1: Create a New Body and Sketch
  - Click Create New and select the Part Design workbench.
  - Create a new body and then a new sketch on the XY plane.
  - I drew a simple "L" using polyline tool which served as the unit cell of the lattice. This shape was fully constrained using dimension and symmetry tools.



• Step 2: Pad the Sketch into 3D
  - I used the Extrude tool to extrude the sketch to a desired thickness (e.g., 5 mm), transforming the 2D shape into a 3D object.
  
  -Created a new sketch on the face of the "L".
  -And made a square at the corner of the "L" to extrude into 3-point "L" using geometry tool and created the square at the corner of "L".
  -Then extruded into 3 point "L".
  - This became the base unit of my lattice matrix.
  - Then joined using Part>Boolean>Union tool.






• Step 3: Create a Lattice with Array Tool
  - I switched to the Lattice Workbench and selected the Array tool.
  - I created a Linear Array to make direction of the copies (5) and the spacing between them (e.g., 20 mm).
  - This produced a repeating matrix of the L unit. -The step repeated for both "L" shapes. -The hole lattice joined using Boolean>Union tool.








• Step 4: Adding a cylinder
  I have added a cylinder form the shapes with radius: 40mm, height: 100mm.
  I moved the cylinder to the middle of the lattice using tranform tool, this is going to be used to shape the lattice.
  I joined them using Boolean>Union tool,
  -Then shape made using Part>Boolean>Inetrsection tool.





• Step 5: Adding a base
  I have created sketch on the bottom plane .
  Created polygone shape and extruded.
  I joined them using Boolean>Union tool,
  -Then shape made using Part>Boolean>Inetrsection tool.




• Step 6: Adding cone
  I have adde a cone form the shapes with radius: 1mm, Second radius: 40mm. I moved the cone on top of the lattice using tranform tool, this is going to be used to shape the lattice.
  I joined them using Boolean>Union tool.



Front view.


Exporting the Model for 3D Printing
Once the design was finalized, I exported it as an STL file for 3D printing:

• Select the body or object in the model tree
• Go to File > Export
• Select STL Mesh (*.stl) and save it to a directory

Slicing the STL for 3D Printing
I imported the STL file into Creality Print software to prepare it for 3D printing.




• Imported the STL file into the slicer workspace
• Used the Scale tool to resize the model to fit the print bed.
• Used Move and Rotate tools to position the object flat on the print surface
• Clicked Slice to generate G-code
• The G-code save and ready for 3D print.


3D Scanning Process for CR-Scan 01 3D 1. Preparation & Environment Setup
• Lighting: Use consistent ambient lighting. Avoid direct sunlight or harsh shadows.
• Turntable: Place the object in the center of a motorized turntable if using automated scan mode.
• Surface: Ensure the object has a matte finish (use scanning spray for shiny/transparent surfaces).
• Warm-Up Time: Turn on the scanner and allow 10–15 minutes to stabilize the structured light projector.
2. Hardware Connection
• Connected the CR-Scan 01 to the laptop via USB 3.0.
• Plug-in power and USB.
• Confirm the scanner is detected in Device Manager or within CR Studio software.
• Launch CR Studio application.
3. Calibration (if required)

Calibration ensures accurate geometry capture. It's optional but recommended after transport or in new environments.

1. Open the Calibration Wizard in CR Studio.
2. Mount the included calibration board on the turntable.
3. Follow the on-screen prompts to move the board to 7 different positions and angles.
4. Wait for each capture to complete.
5. Finish when precision reaches ≤ 0.05mm.
4. Scanning Steps (Turntable Mode Recommended) A. Initial Settings
• Choose "Auto Scan" in CR Studio.
• Set resolution: Low (fast), Medium (balanced), High (detailed).
• Set rotation increment: 15° (24 steps for full rotation).
• Enable auto alignment and texture capture if needed.
>B. Central Scan Pass
• Place object upright at the center of the turntable.
• Start scan – scanner will capture a full 360° pass.
C. Top-Down Scan Pass
• Raise the scanner or tilt downward to capture top areas.
• Re-scan to fill gaps missed from the central pass.
D. Bottom-Up Scan Pass
• Lower scanner or tilt upward.
• Re-scan to capture underside or recessed geometry.
E. Manual Detail Pass (Optional)
• Switch to handheld mode.
• Scan specific regions for refinement.
• CR Studio will merge them later during registration.
5. Real-Time Monitoring During Scanning
• Live 3D Preview: Shows structured light projection.
• Point Cloud Display: Reveals coverage in real-time.
• Color Quality Indicators:
  • Blue: Good scan
  • Red/Orange: Low-quality or misalignment
• Distance Feedback: Keep scanner at 40–60 cm from object.
6. Post-Processing Workflow
1. Registration: Auto-align multiple scan passes into a unified model. Use manual markers if auto fails.
2. Cleaning: Remove floating points, noise, or unwanted surfaces.
3. Hole Filling: Apply AI-assisted fill for incomplete areas.
4. Mesh Optimization: Decimate mesh to reduce triangle count while preserving details.
5. Export: Save as STL (for printing) or OBJ (for textured models). Ensure it's watertight and manifold.