3D Scanning and Printing
Group Assignment
Go to for the group assignment page
Individual assignment
- Test the design rules for your printer(s) (group project)
- Design and 3D print an object (small, few cm) that could not be made subtractively
- 3D scan an object (and optionally print it)
Learning outcomes:
- Identify the advantages and limitations of 3D printing and scanning technology
- Apply design methods and production processes to show your understanding.
Have you:
- Described what you learned by testing the 3D printers
- Shown how you designed and made your object and explained why it could not be made subtractively
- Scanned an object
- Outlined problems and how you fixed them
- Included your design files and ‘hero shot’ photos of the scan and the final object
Week workflow
Weekly assignment → Test Printer → design as object → Print object → Scan object → print scanned object (optional)
Tools used
- Delta 3D Printer
- Mini 3D Printer
- Caliper
- 0.4 mm needle
- Uhu glue
Software Used
Files Generated/used
- Test's stl file: 3D Printer test model from thingiverse
- G-code file: all week's generated G-code from STL files and scanned stone model
- Solid Works file: Project page of the 3D model for a wire organizer used on a CNC I built
- Chain's stl file: Generated stl file from the Solidworks archive
- Printers preparation
- In order to start the test I prepared the printers by cleaning the nozzles and spreading new glue into the platforms
- I tested the extrusion on both printers and it looks good ;
- The limits of our printers
- I started this week's assignment by looking for a test pattern on the website
Thingiverse
. Simply by using its search engine with the keywords,
"test 3d print"
it show various results with the purpose of testing the printers.
- Then I selected one of the designs. It tests different capabilities of the printers.
- Nut, Size M4 Nut should fit perfectly
- Wave, rounded print
- Star, Sharp Edges
- Name, Complex Shapes
- Holes, Size 3, 4, 5 mm
- minimal Distance: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm
- Z height: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 mm
- Wall Thickness: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm
- Bridge Print: 2, 4, 8, 16 mm
- Sphere, Rounded Print 4.8mm height
- Sphere Mix, 7 mm height
- Pyramid 7 mm height
- Overhang: 25, 30, 35, 40, 45, 50, 55, 60, 65, 70°
- Warp, does it bend?
- 3D Print Font, optimized for 3D printing
- Surface, Flatness
- Size, 100 x 100mm x 23.83 (10mm width)
- Spike, minimum Layer Time, 21 mm height from Bottom (include Baseplate)
- Hole in Wall, 4 mm diameter, check for proper print
- Raft Test, raft should be just under the model
- Retract Travel, check retract settings for longer travel
- On the softwareRepetier Host I loaded the stl file and sliced for each printer. Naming the G-code with the printer designation in front.
- 3D printers are far from being plug 'n play devices. There is a lot of adjusting and some of it looks like magic. I will highlight the most important points to pay attention in the settings of the software Slic3r, that works in conjunction with Repetier.
- Still on Repetier in the "Slicer" tab the software presents us with several options of preset configuration. The first is the slicer software itself. On the drop-down menu it is possible to chose from Slic3r, Cura or the older software nobody uses...
- On Print settings we will have characteristics of the particular model you want to print, my current choice is "coarsewithsupport" later on I will discuss how I chose the settings that make up the presets presented;
- Then we have "Printer Settings", normally the settings related to a specific printer (machine) goes here, in my presets I have here the different printers of the lab being one a carteian printer "Mini_2.5_retraction" and another not shown that is a delta printer;
- Here on "Filament Settings" are the many filaments one can have each with its different setting like color, temperature or thickness;
- On this item we will dive deeper on the settings. We will actually setup the presets displayed before.
- So as Slic3r presents in the first column we have the classes: Print settings, Filament and Printer;
- Then we have in the second column drop down menus to chose each preset that the user wishes to customize
- The third column we see an icon in shape of a gear, a typical icon that is for configuration, lets click on it to open each class and see it's entrains.
- Lets see sub-class by sub-class starting with Layers and Perimeters.
- In this area we can see Layer hight this is a important setting that should not go beyond the nozzle diameter size. If you are in a hurry and don't care about the appearances go hight. I have chosen 0.3 mm for a thought feeling. The layers will be noticeable and slopes will look like stairs. If you need a detailed result go low, the limits of how this can go low are near infinite but because time is limited I suggest not going lower than 0.1 mm, lower number means more layers, and it will be smooth as peach skin.
- Now after each tweak click on this strange blue square shape that reminds me of past times before all this excess of information and the echo-chambers, before this true limitless universe of terabytes around us. Its called a floppy-drive. If you don't click believe me you will regret as nothing will be saved, but fear not, Slic3r won't let you do that without a warning.
- Next I took the G-code I had saved on the SD card and placed on the 3D printers and started the print.
- The prints were not bad but there was a lot of oozing (spider web). So I increased the retraction by .5 mm and then by 1 mm the improvements were very noticeable in both printers.
- The results
- Designing and printing an object
- I decided to create a necessary part of my final project. It's a wire organizer that when connected together works as a chain.
- The design is parametric so I can easily change the size as needed
- The steps to design
- As I finished the Solid Works model I then export the file as stl
- Add the stl file
- scale if needed
- rotate if needed
- click on slicer to get to settings and start slicing
- In Configuration you can set particular characteristics of the slicing operation, attached is the config bundle for our printers.
- with the preset loaded here you chose print settings
- here you can select the machine model
- here is filament settings
- finally click on "Slice withSlic3r"
- Click on save to SD card to have your G-code saved to the media you will insert to a 3Dprinter
- In visualization you can see layer by layer and understand how your settings will affect the print before actually printing.
- The settings in the slicer shows that the infill were rectilinear and at 20% and the layer hight was 0.2mm
- Again clicking show layer hight and sliding the last layer will show the layers step by step.
- With the SD card inside check the LCD that will show the nozzle temperature, top left
- press then the rotary encoder to show the menu options
- Scroll to "Print from media" and press the encoder knob
- Scroll to the desired file and press the knob and the print will start
- 3D Scanning
- For that part of the assignment I used Autodesk Remake. It relies on Photogrammetry.
- luckily I was at the beach and I saw a model that would be interesting. Someone had but a large rock equilibrated.
- Next step was to take around 40 photos from all angles and in preference without moving background like people or clouds.
- Next I uploaded the files to Remake. Its important to select only good images and restrict background moving objects. After upload is done press create model. It can take a while during your model generation.
- After upload chose option on the generation process. I chose standard as its free.
- On the lower part of the screen ReMake shows models being generated and on queue. The top part shows models already done.
- With the model ready you can click on it and entering the edit mode of ReMake.
- I compile the editing sequence on the following mosaic, in synthesis. I selected the undesired parts deleted it and filled the holes left. finally I generated a stl file that should be ready to print.
- Preparation of Stone Model
- I clicked on load in other to load the stl file intoRepetier. Stl file here.
- Next find the file in its directory and click ok
- If needed its possible to rotate, scale and etc the model until it fits on the printer area. In my case this was not necessary as the model did fit
- On the tab "Slicer"
- I started by selecting the choice of slicer software, I chose the software called "Slic3r" with a 3 instead of the letter "E", and yes this is a confusing name.
- Next I selected the pre-configured setting coarse with support.
- Then the best option according to the previous tests, Mini 2.5 retraction
- On Extruder there are only one pre-configured in this printer so no choices available.
- Advanced configuration are available on the option "configuration" but in my case it was not needed as the already tested pre-configuration should work fine.
- Finally click on "Slice withSlic3r" in order to start the slicing process.
- Now the model is ready to be printed. This can be done by clicking on the button "Print". The top arrow I point to the statistics of the print, it would take 1:41 minutes to print the scanned model which chose not to do. In the lower arrow its possible to see the support material that was prepared for the print.
- G-code generated
The G-code Generated can be downloaded with the link above but I extracted here the beginning of it in other to show a few of its statistics.
; generated by Slic3r 1.3.1-dev on 2020-05-31 at 20:04:21 ; external perimeters extrusion width = 0.44mm (3.38mm^3/s) ; perimeters extrusion width = 0.48mm (7.54mm^3/s) ; infill extrusion width = 0.48mm (10.05mm^3/s) ; solid infill extrusion width = 0.48mm (2.51mm^3/s) ; top infill extrusion width = 0.48mm (1.88mm^3/s) ; support material extrusion width = 0.44mm (6.76mm^3/s)
While on the 3D printer test model's page I downloaded the design and took note of all the parameters it intends to test such as:
Bellow is the 3D print test model:
The author also supplies an image for reference when checking the print
- This Slic3r is the slicer software itself that is buried deep in the Repetier. Its realms are not for the faint of heart, where wrong moves here, or should I say settings, might render catastrophic results in your prints.
- Now we are in the Print Settings tab:
Now this sub-class of the Print settings is infill. One can save a lot of time and money here. Someone once said they are both the same, frankly I rather own the first than the second: The infill I have is 20% I am not a cheap bastard, I believe 20% is enough after all the ephemeral pieces this printer expels rarely are worth to use all this corn, ah did I mention I am using PLA a derivate of corn, of course not thats later in filaments... So for now believe me 20% is enough for almost all prints. If you need to tow a truck go crazy use 100% if in the other hand you want to make a delicate vase 0% will leave you a hollow print.
On this subsection of Print settings, the famous Skirt and Brim, the savvy fabber can use Brim instead of the ridiculous and wasteful rafts done by those who won't take time to level and calibrate their printers. Well by using a wide brim you make sure your print won't detach from the bed. Brim basically are lines next to each other and attached to the print, its great for a spiky model's base, or just corners that want to take off from the print bed "warping". The skirt is used to kind of clean ones noose I mean nozzle yes the printer nozzle, the part that the filament gets out from. This setting will extrude a line around the model to be printed specially useful when filament promiscuity is the case so when changing colors or filament types be sure to either extrude in the air or add some skirt before your print.
The subclass of Support material I leave for the people who won't challenge their machines for the ones who don't care to calibrate and level.
Starting with Support material you use this for overhangs. Support builds under your model in the places where the negative slope is to steep in other to prevent real birds nest by free forming under your nose I mean nozzle.
Raft, how I hate rafts I don't want to even talk about haft, I wonder how much popcorn has been erased from the universe by the usage of raft! Well like the name implies none want to be on, or use a raft. Its for emergencies and should be kept only for that. It creates a waste of material that will compensate poorly the lack of leveling, its for the lazy but in the end promotes more work as the under side of the print will not ever be as smooth as the printed part that was printed directly on glass. Support also does that. Try printing with support and then spend the next hours post processing your prints, super fun stuff.
The class of filament settings deserves not much time as they are straight forward, if your filament supplier cares about you, he will give you the temperature in which to print in a label in the sides of the box or spool. The diameter is and has always been with me 1.75mm, the thinner diameter is easier to push than 3mm the other standard in filament thickness after all we are pushing filament through a nozzle with 0.4 mm in diameter thats thin so choosing a printer that takes a thin filament is better!
Here in printer settings we find nozzle size, I use 0.4 mm; -next my preferred setting on this tests, well practically the only one I messed with is the "retraction".
As being the designer, engineer and technician of my printers its little what I haven't tried before.
The retraction, yes, the retraction will depend on many factors: -too much retraction and the filament can get stuck in the nozzle guaranteeing one a lot of fun fixing/disassembling a nozzle that the filament froze in higher levels. It's always fun for geeks like me to fix that, NOOOT! Too little retraction and you will have spider web all around your towers. So This is a setting that needs to be tested and tested, until like many other settings. Do trial and error until mastered to what resembles perfection, if that even exists in FDM of course.
Click here for the process of slicing and creating the file with the g-code to print.
| Parameter | Results | ||
|---|---|---|---|
| Mini | Delta | ||
| 1 | Nut, Size M4 Nut should fit perfectly | Yes | No |
| 2 | Wave, rounded print | Yes | Yes |
| 3 | Star, Sharp Edges | Yes | Yes |
| 4 | Name, Complex Shapes | Yes | Yes |
| 5 | Holes, Size 3, 4, 5 mm | 2.9, 3.9, 4.9 | 3, 4, 5 mm oval |
| 6 | minimal Distance: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm | 0.1mm not good | 0.1, 0.2, 0.3 not good scale wrong 6.5mm instead of 7mm |
| 7 | Z height: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 mm | 0.1mm printed with 0.2 and 1.1 with 1 | Yes |
| 8 | Wall Thickness: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm | didn't print 0.1, 0.2 next walls printed as 0.5 until last as 1mm | Yes |
| 9 | Bridge Print: 2, 4, 8, 16 mm | Printed as 2.85, 3.9, 7.9, 15.8 | Yes |
| 10 | Sphere, Rounded Print 4.8mm height | 5.1 | Yes |
| 11 | Sphere Mix, 7 mm height | 7.15 | Yes |
| 12 | pyramid, 7 mm height | 6.95 | Yes |
| 13 | Overhang: 25, 30, 35, 40, 45, 50, 55, 60, 65, 70° | Yes | Yes |
| 14 | Warp, does it bend? | no | Yes |
| 15 | 3D Print Font, optimized for 3D printing | Yes | Yes |
| 16 | Surface, Flatness | a bit rough | Yes |
| 17 | Size, 100 x 100mm x 23.83 (10mm width) | 99.45 x 99.8 x 23.2 (10.2 with) | Yes |
| 18 | Spike, minimum Layer Time, 21 mm height from Bottom (include Baseplate) | 15mm | Yes |
| 19 | Hole in Wall, 4 mm diameter, check for proper print | Yes | Yes |
| 20 | Raft Test, raft should be just under the model | didn't test | Yes |
| 21 | Retract Travel, check retract settings for longer travel | almost no oozing | Yes |
| Conclusion | For a FDM printer I believe the result is very good. The sizes differences are probably due to a PLA shrinkage |
This design is either to hard or even impossible to do with subtractive technique due to its shape and details inaccessible to a 2 axis CNC or even to a 3 axis.
The result!