4. 3D scanning and printing¶

This Weeks’ Task¶

Group assignment

Test the design rules for your printer(s) Document your work and explain what are the limits of your printer(s) (in a group or individually)

Individual assignment:

Design and 3D print an object (small, few cm3, limited by printer time) that could not be easily made subtractively 3D scan an object, try to prepare it for printing (and optionally print it)

===============================================================

What is 3D Printing?¶

3D printing is an additive technology used to manufacture parts. The process works by laying down thin layers of material in the form of liquid/ thermoplastic material like PLA and ABS for FDM.

3D printer¶

We used Fused Deposition Modeling (FDM) printer that works using a plastic filament which is unwound from a spool and is supplied to an extrusion nozzle which can turn the flow on and off. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions by a numerically controlled mechanism. The object is produced by extruding melted material to form layers as the material hardens immediately after extrusion from the nozzle.

Setting parameters - Group assignment¶

1- Infill settings

This is to measure how much material will be printed inside the outer shell of the object. The infill density specified by how strong you want your material to be based on the use of it. Keeping in mind that the more infill density, the more time will take to finish printing the object.

2- Shell thickness

shells are the outlines or outer perimeters of each layer. Depending on the settings of your slicer, you can customize your shells. Increasing the shell thickness also increases the strength of the model. As a result, much more robust objects can be printed. This setting can be changed for most slicers in the settings of your slicer.

3- Layer height

increasing layer height will decrease the resolution and quality of your print. Layer height can be optimized in order to attain the fastest print speed while maintaining a certain amount of resolution. A shorter vertical layer results in a thicker horizontal line, and a taller vertical layer results in a thinner horizontal line. This can throw off precision in the horizontal plane.

3- Overhangs

In general, when your model has an overhang or a bridge which is not supported by anything below, you may need to use 3D printing support structures to be able to 3D print it.

However, not all overhangs need to be supported. As you can see in the picture, we can go up to 85% without support.

===============================================================

Lets model!¶

My 3d design can’t be made subtractively, as it contains curves and angles and details that only a 3d printer can do.

I used Fusion 360 to model a horse

For this model, it was too difficult for me to design all the details of a horse. so What I did is I took an existing STL file of a horse and modify it through fusion.

So here’s How I did it.

Opened fusion and inserted the mesh.

Editing the mesh by adding angular shapes to it.

adjusting the right proportion and number of triangles

Editing the object more and more

Final outcome

===============================================================

Prepare the model¶

First, I imported the design to a Ultimaker cura software.

changing the infill of the design with the shape

checking the support as the software calculates the area’s that needs support and add to it.

Shell thickness is set to 1.2 mm

Pressing slice to estimate the time of the process and how much materials the object requires.

The blue areas are where the supports are added.

Then save it to removables to be saved into the SD card to be inserted to the machine for print.

===============================================================

3D printing¶

Ones we install the SD card to machine, we choose the file and then we start operating the machine.

The bed will start heating up for the material to stick on it. and will start printing.

I left the design and came to it the next day and it was damaged. I think this is because the object moved and didn’t stick on the bed well. So I restarted the whole process.