3D Scanning and Printing

Group assignment:

• Test the design rules for your 3D printer(s)
• Document your work on the group work page and reflect on your individual page what you learned about the features of your 3D printer(s)

Individual assignment:

Design, document, and 3D print an object (small, a few cm3, limited by the print time) that cannot be easily made in a subtractive way

• Scan a 3D object (and optionally print it)

GROUP ASSIGNMENT

³Link to group work:

https://fabacademy.org/2026/labs/lima/Weeks/Week5/Week5.html

Group Objective

Analyze and test the design rules of the laboratory 3D printers, evaluating parameters such as overhangs, bridges, tolerances, wall thickness, layer adhesion, and the use of supports. In addition, understand how print settings influence the final quality of parts manufactured using FDM technology.

Testing the Design Rules of the 3D Printer

As a group, we analyzed and tested the design rules of an FDM 3D printer to understand its capabilities and limitations.

We evaluated:

• Minimum wall thickness
• Overhang angles
• Bridging distance
• Tolerance between parts
• Layer adhesion
• First layer calibration
• Support requirements

Design Rule Tests

We prepared standard test geometries including:

• Overhang test (angles from 30° to 75°)
• Bridging test
• Tolerance clearance test
• Thin wall test

Supports

At the Digital Manufacturing laboratory of IES Huando, 3D printing tests were carried out with the aim of analyzing the behavior of different geometries when printing with and without supports. The purpose was to understand how configuration parameters influence the final quality of the part, especially in cases of overhangs, bridges, and clearance spaces (liquidation), as well as to evaluate how easy it is to remove the support material.

Printer settings

For the first tests, the use of supports was enabled with the following parameters:

• Profile: 0,2 mm
• Infill: 20%
• Support: Enabled
• Print temperature: 215 °C
• Bed adhesion: Edge (Brim)
• Printer: Ender 3

Support was necessary in designs with pronounced overhangs and gaps, since without an auxiliary structure, the molten material tends to move toward the nearest surface, affecting the accuracy and finish of the part.

Overhang

A model with pronounced incline was printed to evaluate the need for support.

• With support: better stability and definition.
• Without support: deformation and material collapse.

Liquidation

The separation between parts or internal cavities was analyzed.

• With support: stable structure.
• Without support: partial collapse of the roof.

Support-free configuration

In the second test the supports were disabled, keeping the other parameters the same:

• Profile: 0.2 mm
• Infill: 20%
• Support: Disabled
• Temperature: 215 °C
• Adhesion: Edge

The objective was to directly compare the results and demonstrate the importance of support in certain geometries.

Other geometric tests

Additional tests were also conducted to analyze other important factors in 3D printing.

Angle

Assessment of the inclination limit without the need for support.

□ Bridge

Printing test between two points separated without intermediate support.

Wall thickness

Structural strength and stability were analyzed according to the configured thickness.

Dimensions

Verification of dimensional accuracy and tolerances.

Anisotropy

Mechanical strength was evaluated according to print orientation, observing differences in the applied force across different axes.

Surface finish

External texture was analyzed according to layer configuration and thermal parameters.

Infill

Comparison of strength and material consumption with 20% infill.

Support optimization

Three attempts were made to configure the support to facilitate its removal:

□ First attempt

It was configured with higher density and less spacing between the model and the support. Result: Difficult to remove, risk of damaging the part.

Second attempt

The distance between contact layers was slightly reduced. Result: Removal improved, but there was still difficulty.

Third attempt

The contact material between support and model was reduced, adjusting the Z distance of the support.

Result:

• Easy removal
• Better surface finish
• Lower risk of damage

It is concluded that the greater the number of lines or layers of contact between the support and the design, the greater the difficulty of removal. A balanced configuration allows stability during printing and ease in post-processing.

The result was that it was easy to remove the support.

https://academy.cba.mit.edu/classes/scanning_printing/index.html

Observed Printer Limits (FDM – 0.4mm nozzle)

• Minimum reliable wall thickness: 0.8 mm
• Overhangs above 60° require supports
• Tolerance under 0.3 mm may fuse
• Bridging works up to 15–20 mm
• First layer calibration is critical for adhesion

What I Learned

• Additive manufacturing requires design adaptation.
• Small dimensional differences significantly affect assembly.
• Cura preview is essential to detect failures before printing.
• Supports must be minimized through intelligent design.

Learning achieved

During the group activity we learned to evaluate the capabilities and limitations of 3D printers through cantilever, bridges, tolerances, wall thicknesses, and supports tests. These tests helped understand how parameters such as temperature, adhesion, print orientation, and support configuration influence the final quality of the manufactured parts. In addition, we identified the design rules that should be considered to achieve more precise, durable, and efficient prints in additive manufacturing processes.

INDIVIDUAL ASSIGNMENT

My process:

Individual Objective

Design and 3D print an object that cannot be easily manufactured using subtractive processes, applying digital modeling principles, print setup, and additive manufacturing. Also, perform the 3D scanning of a physical object to understand the digitization process, point cloud generation, and three-dimensional meshing.

Materials and Equipment

Design of the 3D Object

A three-dimensional model was designed using the Tinkercad software, u, sing basic solid modeling tools.

The design consists of a sphere contained within an icosahedro,n, generated by combining geometric shapes and grouping (group) and subtraction (hole) operations.

The following steps were followed for its construction:

1. Creation of a face-less icosahedron as the main volume

   

2. Insertion of a sphere inside

   

3. Adjustment of dimensions and alignment of the elements

   

4. We export it in .STL format

   

The result is a geometry with an internal volume not accessible from the exterior.

This type of design cannot be easily manufactured using subtractive processes

(such as CN,C), as the cutting tool cannot access the interior of the object without destroying the external structure.

□ Tinkercad design (3D view)

Preparation of the file for 3D printing

I exported the file in STL format and went to the official Ultimaker Cura page to download the software.

I installed the program and configured the Bestgee T300S printer.

I imported the STL file into Ultimaker Cura. Within the software I modified the dimensions by reducing the size to 70%, obtaining an estimated print time of 2 hours and 11 minutes.

Printing process with Bestgee T300S

I turned on the Bestgee T300S 3D printer and verified that the bed was clean and properly leveled.

The extruder heated to 200 °C and the heated bed to 60 °C to work with PLA filament.

I performed the leveling by adjusting the Z axis (Z-offset), leaving approximately 1 millimeter of separation above the bed and verifying the calibration with a sheet of paper.

I loaded the PLA filament into the extruder until I verified it flowed correctly and finally started the print.

The print was tested in the laboratory, obtaining a satisfactory result.

• Set the Z axis with a 1 millimeter space between the bed and the extruder.
• The X and Y axes were configured automatically.
• The material used was 1.75 millimeter PLA from the León brand.
• It was expected that the bed would heat to 60 degrees and the extruder to 200 degrees.
• The work area was 20 x 25 centimeters.
• stl file
• Regarding the software used, it was Cura, having to search among several printer options for the one it was connected to.

During the process, it was possible to visualize on screen the point cloud that was progressively generated. This point cloud represents the spatial information captured by the scanner.

other little designs….

I also printed a padintong bear with tree support.

3D Scan

The scan was performed using the Matter and Form equipment with MFStudio software.

Process:

1. Calibration with a pattern
2. Object capture
3. Point cloud generation
4. Automatic meshing

Difficulties were identified due to the object's dark color, which affected the initial capture, resolved by parameter adjustment.

3D Object Scanning

For the scanning process I used the Matter and Form 3D scanner together with MFStudio software, which allows direct communication between the hardware and the portable computer.

Scanner calibration

First I opened MFStudio and selected the 'New Project' option to start the scanning process.

New project

Subsequently I prepared the equipment, connecting the scanner to the power source and to the laptop via the USB cable. I verified that the device was correctly recognized by the software before continuing.

As the next step I selected the “Calibrate” option, since this procedure is essential to ensure that the scan has accuracy in dimensions, alignment, and depth.

For automatic calibration I placed the board of small white and black squares in front of the scanner, as indicated in the equipment manual. This plate allows the system to recognize the geometric patterns needed to correctly adjust light, distance, and focus.

During the process, the scanner projected light lines that moved horizontally and vertically over the calibration plate. This allowed the system to adjust light intensity and the alignment of optical sensors.

Has it passed? Would you like some time to revert to calibrating your last one now?

I waited a few minutes until the software confirmed that the calibration had been completed successfully.

Scanning process

Once the equipment is calibrated, I placed the object in the shape of a black pyramid at the center of the scanner's rotating base. It is important to correctly center the object to avoid deformities or loss of information at the edges.

When starting the scan, I observed that the lines projected on the pyramid's surface allowed capturing the volumes and edges. However, in an initial test I noticed that some lines came out misaligned due to the object's dark color and the inclined geometry of its faces.

Calibration in progress. Please do not touch the object or move the scanner.

Therefore, I performed a reconfiguration of the scanner by adjusting parameters such as exposure and capture sensitivity, which helped improve the definition of the edges.

Here we will use the 3D scanner to start scanning a duckling; before that, we will calibrate the scanner, noting the different heights that can be scanned

From there we will click the scan button and we will wait for the machine to do the job.

Regular scan

Now gives you the scanned image; well, at least part of it, and we see how the image is gradually being generated.

And we see how the image of the duckling is generated on each side

We remove the noise which are the points of the image that we do not need of

We will proceed to meshing the image to be able to generate a compact image

Upon finishing, the software performed automatic meshing, transforming the point cloud into a three-dimensional solid surface.

We proceed to save our duck file in 3D.

3D printing preparation

Once the digital model was obtained, I export the file in STL format for subsequent printing.

or

I opened the file in the slicing software and verified that the dimensions were correct. Then I centered it on the virtual print bed and generated the corresponding .G code.

During 3D printing, the layer-by-layer construction process could be observed. First, the base of the pyramid was printed, ensuring good adhesion to the heated bed.

Subsequently, the inclined faces were formed until the structure was complete.

In the final stage it was verified that the print was completely finished and that the edges maintained a defined and stable shape.

Scanned Extra:

Comparison and analysis

Finally, I compared the original object, the scanned model, and the 3D-printed piece.

It could be observed that the scan managed to reproduce the general geometry of the object quite accurately. However, small variations were evident in hard-to-reach areas or in the most pronounced edges, which is common in optical scanning processes.

This exercise helped me understand the importance of proper calibration, as well as the influence of color, texture, and lighting of the object on scan quality.

Problems and Solutions – 3D Scanning and Printing

Problem 1: The 3D print showed poor bed adhesion

Solution:

The print bed was properly leveled and the base temperature was adjusted to improve filament adhesion.

Problem 2: The 3D model had errors or incomplete surfaces

Solution:

The STL file was repaired using mesh correction tools before exporting for printing.

Problem 3: The print presented deformities (warping)

Solution:

Print speed was reduced and better ventilation and appropriate temperature were used to avoid deformities.

Problem 4: The 3D scan did not correctly capture some details.

Solution:

Ambient lighting was improved and scanning was performed from different angles to obtain a more accurate capture.

Problem 5: The printed part did not fit correctly.

Solution:

CAD design tolerances were adjusted and scale tests were carried out before the final print.

Problem 6: The filament jammed during printing.

Solution:

The printer nozzle was cleaned and it was verified that the filament was fed correctly.

Learning achieved

During this week I learned the basic operation of 3D printing and scanning, understanding how configuration parameters influence the final quality of the parts. I also understood the importance of bed calibration, proper use of supports, and correct preparation of STL files before printing.

Furthermore, I learned that 3D scanning greatly depends on lighting, color, and geometry of the object, making parameter adjustment necessary to obtain better results. The experience allowed integrating digital design, additive manufacturing, and digitization of physical objects within the digital manufacturing workflow.

📋 Check-off List

❓ Frequently Asked Questions

1. Should I include my scanned file(s)?

Answer:
Response: It is not mandatory to include the full 3D scan files. In my work with the Matter and Form scanner and MFStudio software, the process was documented with screenshots of the scan, the point cloud, the meshing, and the final model. This is sufficient to evidence the workflow, since the files can be

heavy and difficult to upload to the web.

2. Do I need to clean my 3D scan?

Answer:
Response: It is not mandatory to clean the 3D scan, but in my case it was useful to make adjustments during the process. When scanning objects like the duck, noise was generated in the point cloud due to lighting and the color of the object. Therefore, unnecessary points were removed before the automatic meshing in MFStudio, which allowed obtaining a more stable model ready for subsequent printing.