5. 3D scanning and printing¶

This week’s group assignment was to test the design rules for our 3D printer(s).

Design Rules outlines the important considerations when designing for 3D printing, in order to get a good finish and reduce overall production time. The Design Rules published by ProtoLabs provides a good reference point for major printing processes.

Overview¶

Which 3D Printers we tested¶

We decided to characterise the design rules for these 3D printers: | Specs | Anycubic i3 Mega S|Bambu Lab P1S| Creality K1C | | ---- | ---- | ---- | -----|----| | Slicer |Anycubic Slicer| Bamboo Studio|Creality Slicer| |Build volume, mm| 210 x 210 x 205|256 x 256 x 256| 220 x 220 x 250 | |Layer height, mm|0.05~ | 20%-70% of nozzle diameter| 0.1-0.35mm | |Positioning Accuracy (Precision), mm|X/Y 0.0125 Z 0.002| around 0.1 | 100±0.1mm | |Filament diameter, mm|1.75 |1.75| 1.75mm| |Nozzle diameter, mm| 0.4|0.4| 0.4 | |Materials Supported| TPU, PLA, ABS, HIPS, Wood| PLA, PETG, TPU, ABS, ASA, PVA and PET, and even PA PC, etc.| ABS/PLA/PETG/PET/TPU/PA/ABS/ASA/PC/PLA-CF/PA-CF/PET-CF | |Print speed, mm/s | 20-100 | max 500| 300mm/s Max: ~600 | |Print bed temperature | 110 °C |55°C for most PLA| ≤100℃ | |Extruder temperature |260 °C | 300°C| ≤300℃ | |Input Formats|STL, OBJ, DAE, AMF| .3mf, .stl| STL, OBJ, 3MF |

Test model¶

After considering different tests, we decided on the All in one 3D Printer Test 2 and Clearance and tolerance test.

All In One 3D Printer test (Made on November 20, 2017)
Smaller, more effective version of above(Made on June 24, 2018)
All in One 3D Printer test 2(Made on February 14, 2024)
All-in-One Object from Kickstarter-Autodesk-3d(2018) - according to Nagano-san, this one takes 9 hours to print
This one is not new but has 21 tests and prints in 1+ hour?
https://fabacademy.org/2021/labs/waag/students/nadieh-bremer/blog/week-5/
Comprehensive one made in 2025

Printing settings¶

We used these parameters when printing; | Parameter | Description |Value | | ----- | -----| ----| | Infil Density | Expressed as a percentage, ranging from 0–100%. Higher infill percentage results in a denser, stronger print, while a lower percentage makes the object lighter but potentially less durable | 15% | | Support | Use if over 45˚ | None| | Skirt | Good for purging nozzle before printing model | 2 | | Brim | Good for incresing bed adhesion | 0 | | Raft | Good for clean first layer of model | 0 | | Layer Height | Smaller layer height produces a smoother surface finish but takes longer to print; a larger layer height prints faster but may have visible layer lines depending on application. | 0.2mm | | Print speed | Depends on printer. To get more details, consider reducing speed. | 300mm/s for Inner wall, 200mm/S for outer wall |

Printing Temperature was different for each printers:
Extruder temp, ˚C Build plate temp, ˚C
Varies depending on material. Plastic filament is usually between 205-225.

Summary of Results¶

Below are the test results, alongside ProtoLabs’ design rule recommendations for FDM printers.

Design Rule	Description	ProtoLabs’ recommendation
Time to print	Depends on object’s volume, complexity, and printer’s capabilities
Support & Overhangs	The maximum angle a wall can be printed at without requiring support	45°
Horizontal Bridges	The span a technology can print without the need for support.	10mm
Pin diameter	The minimum diameter a pin can be printed at.	3mm
Holes	The minimum diameter a technology can successfully print a hole.	Ø2 mm
Minimum features	The recommended minimum size of a feature to ensure it will not fail to print.	2 mm
Tolerance	The expected tolerance (dimensional accuracy) of a specific technology.	±0.3% (lower limit ±0.3 mm)
Connecting/Moving parts	The recommended clearance between two moving or connecting parts (minimum space needed between each object), so that they can move after being printed.	0.5 mm

Test 1. Anycubic i3 Mega S¶

Time to print: Expected: 2H 31M, Acutal: xxx

1. Overhangs¶

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Ability of the printer to accurately produce overhanging features without supports.

What is the maximum angle the printer can print in good quality? = XXX°

2. Horizontal Bridges¶

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Ability of printer to create horizontal bridges between two points without support structures.

What is the maximum length the printer can print without drooping or sagging? = XXXmm

3. Dimensional Accuracy (Diameter/Clearance)¶

<br>
The difference in diamter of printed filament versus the acutal design.

What value to consider offsetting when designing? = XX mm (Autodesk’s criteria For reference:)

Target	measured x	measured y	x error	y error
25
Average		xx

Total Average (Avg Error X, Avg Error Y): 0.mmm

Value	Points
0.00 - 0.10mm	5 points
0.11 - 0.20mm	4
0.21 - 0.30mm	3
0.31 - 0.40mm	2
greater than 0.40mm	1

4. Fine Flow Control¶

<spires>
How well the printer can make small spires. Measure the height of the tower that can be made, and whether there are any strings between towers.

Autodesk criteria:
Spines less than 30mm: 0
Spines greated than 30mmm, but strings: 2.5
Spines greated than 30mmm, no strings: 5

5. Negative feature resolution¶

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Ability of the printer to make holes, and their tolerance (how easily the holes can be easily released with your fingers)

6. XY Resonance¶

Not in the All-in-one test?
How well the printer makes prints in the XY direction. Illuminating the test print from the side to identify any visible ringing.
If any rippling in the X or Y axis is observed at or past three hash marks, record a “fail”, otherwise, record “pass”.

7. Z-axis alignment¶

Not in the All-in-one test?
The Z-axis controls the vertical movement of the print head and the build plate. If the Z-axis is misaligned, loose, or dirty, you might end up with uneven layers, gaps, or even failed prints.