6. 3D Scanning and printing
Goals
Our group focus this week was to test the design rules for our 3D printers. In our lab we split up and testing the Prusa Mini, Bambu X1 Carbon and Formlabs 3B. You can see it here. In general it seems to have some variability by machine and even by filament. Knowing your machines and supplies will lead to more consistent results.
Individual assignment: - design and 3D print an object (small, few cm3, limited by printer time) that could not be made substantively - 3D scan an object (and optionally print it)
Accomplishments
- Designed an interlocking bracelet and printed it
- Learned how to use my phone to 3D scan
3D Printing pros and cons
3D printing allows you to run very complex job with much less design constraints compared to traditional manufacturing and can be especially helpful in deign as well as operational uses in remote location such as the space station. In addition, the speed in which you can turn a digital design in to reality is a game changer for rapid prototyping.
However, for large batch manufacturing it is not cost competitive, it has much more limited materials and longer time per part. In addition while 3D printers have gotten a lot more user friendly they are not even close ot being "plug and play by the average user in term of simplicity of use and reliability.
In summary current 3D printer technology is a game changers for some use cases such as rapid prototyping, certain dental/medical procedures and others. It will still require another round or two of evolution to take on main stream manufacturing.
Spinning bracelet
I like ball bearing and so I wanted to make a bracelet that have some similarity.
I started off with Fusion360
I set up a sketch to set up overlapping profiles and then used the revolve functions to create the basic shape
I created a sliced view so I can make sure we have an designed that would stay together but be far enough apart for each part to spin independently
I decided to add some holes for design and in order to see the internal workings a bit better
Here is an overview view of the bracelet.
Rounded out all the edges
Set it up for printing in the Prusa slicer
The first print failed
I gather it was because the bottom of the middle ring was a little high then the other two and so I sliced it again with support
It printed this time but the post production effort to take out all the support was high and left the print looking not great in my opinion
I wanted to print it without support and so I went back to the design and created a construction line and used a constraint to make all the pieces aligned.
That was much better!!
An here you can see the print in place piece all moving independently
3D Scanning
This was a bit more of an issue and having decided to use my phone as a starting point i trying a number of apps
I tried SCANN3D and Polycam
For the SCANN3D I have tried 2 different objects and
SCANN3D
- Clementine / Stainless steel jar - Fail
At first I thought it was going ok but then if started failing
and then started crashing
Given I following the instruction in detail I decided to try another app before spending too much time on this one
- Polycam - first tried to scan a remote control but never got enough of the Z and it merged into the ground
In this app, you choose to add a capture and then you slowly take a video of your object from all side or pictures
Then you upload to get the 3D image
I decided to use a plate and try and avocado It was better but captured a lot of the back ground so I decided to crop it which was easy in the app
This was better but sill not did not separate from the ground
I change my approach and use a ketchup bottle and working on the angles of the pictures I was taking
The angle and overlap of the pictures seem to help but we were still off.
I decided to try my little bulldog ceramic and did 2 full 360 with different angles and got a pretty good output after I cropped it
Here are the files for this week