3D Printing and scanning



For this week's assignment we are supposed to design and print a 3D object that cannot be made using subtractive technique for example milling.
Also we need to scan a 3D object using a 3D scanner.


3D printing is an additive fabrication technique. The idea behind it is to heat a material like PLA and extrude it through a nozzle while moving along the 3 axes according to the G-code of the job adding layers of material one on top of the other until the object is formed.


3D Designing and Printing

First step was to design the 3D object. I used Solidworks to fulfill this task

Designing:

My Idea is to design a chain that forms a closed loop. The reason why this can not be done suptratively is because of the undercuts and hidden spots that the milling machine wont be able to mill.

-I started by choosing to design a part and then created a new sketch.

Mountain View
Mountain View

-I started by drawing 2 elipses using the elipse tool and setting the 2 radii of each elipse.

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Mountain View

-I constrained the 2 elipses to be concentric by selecting them and then right clicking and choosing concentric constraint.

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Mountain View

-Next thing I did was to extrude this drawing into an object.

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Mountain View

-I filleted the edges of my object using the fillet tool.

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Mountain View

-This is the first part of my model at this point it was done. The second part is almost exactly the same except that the 2 radii of the elipse are the same in other words the base of the sketch is a circle this time not an elipse.

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-I went on with creating the third part. I used pretty much the same sequence. Firstly I created a new part and started a sketch. Then I used circle command, then extrude and finally fillet.

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-For the fourth part I wanted to add an extruded text. I used the text tool to add the text .

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-I extruded the text using the extrude tool. This was the final step now I have the fourth part ready.

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-For the final part I used the FabLab logo DXF file I already made before as part of Week three assignment. I created a new part and imported the file.

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Mountain View

-I extruded the drawing into an object using extrude command.

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-Next thing I did was to scale it down by going to Insert >Features >Scale ,then I entered the appropriate scaling factor and pressed Ok.

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-At this point all the parts were ready to be assembled. I created a new assembly by clicking on Make Assembly from Part from file drop menu.

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-I inserted all the other components to the assembly by clicking on browse and choosing the components.

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-After inserting all the components I started assembling them by placing them correctly.
Here are the commands I used:
First: I selected the first component, right clicked and chose Move with triad


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Mountain View

Second: I Copied part one and part two couple of times as I will need them, I did this by selecting them and pressing CTRL+C then CTRL+V.
Third: I used the move commmand. I chose to move by Detla XYZ.
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Mountain View

I kept using those commands until I reached what I wanted

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Mountain View

Slicing:

I used Cura to slice my model for Ultimake 2+ printer with nozzle diameter of 0.8mm.

-Here are the settings that I used:
Layer height: 0.07mm --> The thinner the layer height the better the quality, I wanted good quality
Wall Thickness: 0.7 mm--> Because some parts of the chain were really small I chose to go with a thickness less than 1mm
Top/Bottom Thickness: 0.6mm--> Same as with wall thickness
Infill denisty: 25%--> Because it's a small piece and it's not going to sustain any forces or stresses
Print speed: 50mm/s--> It's a moderate speed to get good printing quality
Travel Speed: 120mm/s--> Also affects the quality of the print if the head moves too fast after printing it may cause some damage
Enable support: Yes--> As some parts are not touching the builplate of the machine
Support placement: Touching Build Plate
Support Pattern: Grid
Support Denisty: 25%--> I tried with less but I saw that not all the parts are properly supported
Support Z Distance: 0.4 mm--> Distance between support and actual object in Z direction, The less the distance the better the quality of the surface but also the harder to remove support later on.
Support X/Y Distance: 1mm--> Horizontal distance between the object and support, I wanted to be able to remove support easily without breaking the small pieces
Build plate Adhesion Type: Brim--> Makes a brim around the object to fix it to the buildplate
Brim Width: 3--> Because the object is really small so no need for more than this

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Mountain View

Printing:

I used Ultimake 2+ printer with nozzle diameter of 0.8mm along with PLA of diameter 2.85 mm.

-Here is how it looked after printing and before removing supports
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Mountain View

-Here is how it looked after removing supports

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Mountain View
Mountain View

Problems and Commments:

-During my first printing trial I was using 8% infill for support I thought that it would be okay but I noticed that it was not good enough to hold the details of the model so I increased it to 25%.

-One other problem was that not all of the text part was not printed succesfully some pieces are missing.

-Also the surface of the model facing the supports came out a bit rough I would say that this is because of the Z Distance but I believe it would have been very hard to remove the supports if I decreased the distance because of the small size of the object.



3D Scanning


-I used Sense 3D scanner along with its Software .


This is the object I scanned
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-First step is to choose the object to be scanned. I chose object.

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-Then I chose small size object.

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-I started the scan while focusing on the object.

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-When I finished scanning I pressed Solidify.

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-This is how it looks after I trimmed some parts of it and erased some noise.

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-I saved the file as STL and opened it in Cura.

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Downloads

-Chain files
-Scan file





Source code is licensed under the terms of the GNU Lesser General Public License v2.1 (LGPL).

Projects, drawings, images and videos are licensed under Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0).

Ahmed Abdellatif 2017