Week 05

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

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

☑ Linked to the group assignment page.
☑ Explained what you learned from testing the 3D printers.
☑ Documented how you designed and 3D printed your object and explained why it could not be easily made subtractively.
☑ Documented how you scanned an object.
☑ Included your original design files for 3D printing.
☑ Included your hero shots.

Design thinking for my sample 3D printing

For my final project, I might need to construct some movable panels for my musical box to project the photos onto a panel. With this idea, I have decided to 3D print the hinges of the movable panel using print-in-place method. In order to demostrate my idea, I have designed a hinged cover box for my portable powerbank. Picture below shows the original cover that it should be like:

Steps of Preparing my 3D printing files

At first, I need to take down all the important dimensions and input to the parameters table. In case of changing any dimensions after theting with the actual product, I can still modify them to a more appropriate size.

Next, I will start off with constructing the hinge of my covered box - the dimension are shown below, and then revolve them.

Subsequently, I have created boxes on both sides, with some small tolerance to work with, and closed by a triangular spring lock. The final design will be like:

First print out on my draft model

After the initial model has been constructed, I am using BambuLab X1C 3D printer and use the PRESET setting - 0.28mm Extra Draft @BBL X1C to print a draft model out and check for the tolerance of:
1) The gap between the 2 covers when it closes.
2) The hinges movement.
3) The locking system.
The print out is as shown below:

There are a few things to take note:
1) the gap between the 2 covers are just nice, even though i have offset 0.25mm from each side.
2) the hinges are too loose.
3) the latch broke after a few rounds of open-and-close process due to thin thickness.

Second print out on my draft model

I have made 2 changes of the dimension below:
1) the gaps between the hinges reduce from 0.50mm to 0.25mm.

2) the latch thickness has increased to withstand the force when closing or opening the cover.

It turns out that the covered box is sturdy (refer to the snapshot and a recorded video below)

Reflection

Through this week, I have learnt a very important lesson on designing a hinge based on the 3D printer that I choose. This can direct apply to part of my final project, which is the hinged cover for photo screening. This is something that ONLY 3D printing can do but other digital fabrication tools cannot.

Software to Choose for 3D Scanning

In general, Singapore Polytechnic Fablab has some fantastic devices to deal with 3D scanning, but I am not going deep into those devices. Main reason being that I am a bit of behind the time to catch up-to-date assignments and starting to design my final project.
Therefore, I am dealing with some simple software application using my own personal handphone to clear this 3D scanning session. And the handphone application that I have selected is called "POLYCAM".

Workflow on using POLYCAM to scan 3D models

* I have prepared the model that I wish to try and scan, which is a metronome for piano and download POLYCAM application.

* I placed the object where I wish to scan on a stable surface with good lighting. I also ensure that the object is well-lit and evenly illuminated from all angles to capture details accurately.
* I started the scan by launching the app initially and press "NEW SCAN". I positioned my handphone so that the object fits within the frame of the camera view.
* I tap the "Start Scan" button to begin the scanning process. I slowly move my handphone around the object and capture the reference frames and ensure that my handphone is keeping within the camera's view.
* I continued scanning the object from various angles until I had captured all sides and details. Polycam will automatically stitch together the individual reference frames to create a complete 3D model.

* After scanning complete, I reviewed and edited the 3D model within the POLYCAM software before I save the as GLTF format, as this format is the only FREE software inside the application.

Sending for 3D printing

I wish to 3D print my scanning model, but GLTF format is not a recognized files for my 3D printers. After clarified with my group buddy - Florimond Chu, Blender software allows me to convert GLTF file to STL file in order to allow my 3D printer to print a sample model.
After obtaining the STL file, I am planning to 3d-print it using BambuLab X1C:

Reflection

I personally don't like 3D scanning due to several reasons, but the main reason behind is because the process is tough to capture a good files for printing. I have difficuilty in maintaining the same posture for a long period to walk around and scan the object.