Week 5 > 3D Scanning and Printing

Group Assignment

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

   - **Test the design rules for your 3D printer(s) >** understand the capabilities of your 3D printer

Describe your 3D printer

make and model At Fablab Winam we use Origianl PRUSA i3 MK3S+ manufuctured by Prusa Research.

motion system type Catrtesian motion system (Bed-slinger design) X-axis-:Belt -driven carriage on linera rods Y-axis: Belt-driver mvoing heated bed Z-axis: Dual lead screws with stepper motors

    trinamic silent stepper drivers with sensorless homing

print volume 250mm X 210mm X 210mm(X x Y x Z)

nozzle type and size Brass nozzle (E3D V6 style)

0.4 mm diameter

max nozzle and bed temp Max Nozzle temp 300’C Maximum Bed Temp: 120’C

control software

Firmware: Prusa Custom firmaware Slicing Software: Prusa Slicer https://www.prusa3d.com/page/prusaslicer_424/ Interface: LCD dislay with SD card Support

print a characterization/test object that tests your 3D printer’s capabilities (and weaknesses)

To evaluate the printer, we printed the following test models: Testprint

Complete 3D Printer Stress Test (All-in-One)

Clearance / Tolerance Test Model

Results and Observations

• overhangs The printer handled moderate overhang angles well (up to ~80°). However, at steeper angles, slight sagging was observed.

Conclusion: Good cooling performance, but extreme overhangs may require supports.

• dimensional precision - clearance

fine detail

Most of the small text was difficult to read. Some letters were unclear.

Conclusion: The printer struggles with extremely fine text below 0.4 mm nozzle resolution. For readable text, letters should be at least 0.8–1 mm thick.

bridging

Bridging performance was good. The horizontal spans were printed cleanly without major sagging.

Conclusion: Cooling and extrusion settings are well tuned for bridging.

surface quality

Surface finish was generally smooth. Minor layer lines are visible (expected with 0.2 mm layer height).

No major blobs or extrusion artifacts were observed.

artifacts Minor artifacts observed:

Slight ringing on vertical walls

Small blobs at layer start/stop points

Possible causes:

Belt tension

Retraction tuning

Print speed

Printer Limitations

1. Speed Constraints

Optimal quality achieved at 40–60 mm/s

Higher speeds reduce surface quality and precision

1. Size Constraints

Maximum print volume: 250 × 210 × 210 mm

Large prints increase risk of warping

1. Precision Constraints

Functional tolerance: ~0.3 mm

Fine details below nozzle diameter (0.4 mm) lose clarity

1. Material Constraints

Printer supports:

PLA

PETG

ABS

TPU (with slower speeds)

PLA produced the best dimensional accuracy during testing.

What We Learned

Cooling plays a major role in bridging and overhang quality.

Nozzle diameter limits minimum detail resolution.

Proper clearance must be designed (≥0.3 mm) for moving parts.

Print speed directly affects surface finish and precision.

Test prints are essential before fabricating functional parts.