Week05: 3D scanning and Printing¶

Group Assignment

test the design rules for your 3D printer(s)

This group assignment document was written by Naoki Hayashi.

Group Assignment Overview¶

3D printing

Slicer
Design rules

3D printing¶

We test the design rules for the Bambu Lab P1S, FDM 3D printer recently intorduced at FabLab Kannai.

P1S

Basic specs:

Build Volume(WxDxH)	256 x 256 x 256 mm³*
Hot End	All-Metal
Nozzle	0.4 mm Stainless Steel Included
Max Hot End Temperature	300 ℃
Nozzle Diameter	0.4 mm (Included), 0.2 mm, 0.6 mm, 0.8 mm (Optional)
Max Build Plate Temperature	100℃
Max Speed of Tool Head	500 mm/s
Max Acceleration of Tool Head	20 m/s²
Air Filter	Activated Carbon Filter
Supported Filament	Ideal: PLA, PETG, TPU, PVA, PET, ABS, ASA Capable: PA, PC
Chamber Monitoring Camera	Low Rate Camera 1280 x 720/0.5fps Timelapse Supported
Filament Run Out Sensor	Yes
Weight	17.60 kg
Electrical Requirements	100-240 VAC, 50/60 Hz, 1000 W @220 V, 350W@110V

1. Slicer¶

A slicer is software that converts a 3D model (STL format) into G-code instructions for 3D printers, mainly used in fused filament fabrication and similar processes.

We used BambuStudio. Below is a steps to use BambuStudio.

Settings:
- Go to “Prepare” tab on the top
- Choose printer you use: Printer > Select printer
Choose filament: Filament > Select filament type (multiple types can be set since P1S combo can install multiple filament)
Import and arrange
- Import files
- Auto orient and Arrange
- Or manually Move / Rotate / Scale
- Right click > Clone to duplicate models
Process (set print parameters): Below is a shortlist of the key parameters
- Choose print preset: We used “0.20mm Standard”
- Customize the preset (“Advanced” mode allows more customization)
  - Quality
    - Layer height: 0.2mm
    - Seam is visible gap between the start and end points of each layer’s perimeter in FDM 3D printing.
      Seam > neareset / aligned / back / random
    - Ironing is a 3D printing feature that smooths the top surface of a model by extruding a small amount of material
  - Strength
    - Walls: 2
    - Infill patterns and density
  - Support > Enable support
    - Type > noraml / tree
    - On build plate only
    - Raft helps adhesion
- Customized preset can be saved
Once all parameters set, “Slice” (automatically go to “Preview” tab)
Preview layers, estimated print time, filament etc.
Export sliced G-code file to SD card (if the printer connected wirelessly, it can be directly printed)

2.Design rules¶

Supports / Unsupported
1. Overhang: A few mm overhang worked but not good appearance
2. Clearance: 0.2 mm or larger clearance worked but 0.1 mm clearance didn’t work
3. Angle: Worked fine until 30°, 20° and smaller angles still worked okay but not good in appearance
4. Bridging: 20 mm bridging still worked, but inner surface is not good in appearance
Surface finish: Layer mark become more apparent on more horizontal surfaces
Wall thickness: 0.4 mm thickness wall is fine, smaller walls are ignored in slicer app. Whereas, 0.1 mm slit hole still visible.
Dimensions: Telerances are surprisingly accurate. Outer and inner dimensions are slightly became smaller. We also compared the same data in Bambu Lab P1S and Creality Ender 3 V2, difference were small.
Anisotrophy: We tested it by printing a L-shaped object. When bending it, it broke at the joint point, in the layer direction; FDM 3D printed objects are weaker in layer direction.
Infill: We tested 0%, 15%, 50% and 100% infill. In BambuStudio, it can be controled at “Strength > Sparse infill > Density”