coursera-assistant-3d-printing-revolution
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docs
/02_module-1-what-is-3d-printing
/04_more-3d-printing-insights
/01_3d-printing-demonstration-danny-lohan.en.txt
[MUSIC] Hi. | |
I'm joined by Danny Lohan. Danny is a graduate student here | |
at the University of Illinois, and was one of the first gurus we found | |
on the online MakerLab back in 2013. Danny knows more about 3D printing | |
than just about anybody that I know. I thought he'd be a great ambassador | |
in terms of showing us how to turn your ideas into objects. We go through three steps. First of all, how to take an idea and | |
create it using a 3D modeling program. In this case, Dan will be demonstrating | |
very quickly a program called Fusion 360. >> That's right. >> Second, how to prepare that digital | |
file for printing on a 3D printer. And finally, how to actually take | |
that file, put it on a printer, and come out with a finished object. Danny, what are you going to | |
show us how to make today? >> Today, I think we will go | |
through making a jet airplane. The reason I choose this object is | |
because the software, Fusion 360, makes it really easy to | |
model parts such as this. >> Danny, | |
what's the first step in this process? How do you go from an idea | |
to an object like this? >> The first step is to choose | |
the appropriate software and as I mentioned, | |
today we're going to use Fusion 360. >> Fusion 360 is an Autodesk product. >> That's right. >> It's one of the most advanced | |
modelling programs out there. >> That's right. >> We're actually, if you stick around | |
with the rest of the specialization, in the software portion, the software | |
course of our 3D printer specialization, you actually get the hands-on | |
instruction by Jeff Smith who works for Autodesk and is a Fusion 360 ambassador. You should be able to, by the end of that course, learn how | |
to make things like this, right Danny? >> That's right. >> Go ahead and take us through the steps. >> Sure. The first thing we're going to have | |
to do is open the software package. This is the icon for Fusion 360. If we click on that, | |
it'll start opening the software. Now what's unique to this software | |
is it's actually cloud-based. >> What does that mean? >> That means you'll need some internet | |
connection to login to the software and through that connection and your account, all your part files will be saved online | |
>> Are there advantages to being online? Could you share your files with people | |
working in other parts of the world? >> That's right. Fusion 360 makes it easy to collaborate | |
with people around the world or locally when working on a part file. >> Okay. | |
Now what do we have here, Dan? Looks like we have a topographical | |
map without anything on it. >> This is the user interface for | |
Fusion 360. The reason I'm using Fusion 360 to design | |
this airplane is that Fusion 360 doesn't work like traditional CAD programs, | |
where you have parametric modeling. It actually uses something | |
called T-splines. You can think about it like sculpting. We can start with a block of material, | |
say clay, and we can pull and morph it until we get a shape like | |
the airplane in just a few minutes. I'll show you a quick example. If we create this tool, | |
we enter the form environment. In the form environment, | |
we can input objects and modify those basically free form. Here we have an object. One thing you would need to do is define | |
how many faces and edges are in this part. You can do that with | |
the dialogue box presented. >> Now what's a face and what's an edge? >> An edge is represented by the line and four lines connected together | |
usually represent a face. Beyond the creation tool, we can use the | |
modified tool which has a wide assortment of modifications we can use to change the | |
shape and sculpt this into an airplane. We can directly pull, push, and modify this object with | |
simple clicks of a button. Once we have our desired faces | |
selected by clicking the alt button, we can extrude this face | |
by selecting one of this outer rim of icons, | |
we can resize the objects or faces. This way, we can increase the size | |
of our object by molding it. In order to create the wings, we can | |
select one of the surfaces or more and use the extrude function | |
to pull that surface out, resize it and reposition it. We can do the same on the other side for | |
the second surface. By doing similar procedures, we can repeat this on all the surfaces to create | |
different features on the airplane. >> Are there any tests in | |
Fusion 360 to let you know that the actual design can be 3D printed? >> What's really nice about Fusion 360 is | |
if you create this whole model in the form environment, it is guaranteed to be | |
watertight and ready for printing. You do not have to take additional steps, | |
like you might with other software, to make sure that you | |
can 3D print your part. >> What is watertight, | |
what does that mean? >> Watertight means that | |
there is a closed surface. You can imagine dropping | |
this airplane in water, water would not go inside the airplane. >> And to print an object, | |
it should be watertight, correct? >> That's right. >> Why don't you go ahead and take us | |
through the steps in terms of moving from this finished 3D model in a Fusion | |
360 to the next step in the process, which is preparing the design file for | |
printing. >> What you need to do is go into the file | |
menu, and click the 3D print button. >> A 3D print menu item. >> That's right. | |
>> Makes it easy. >> From here, we can select the object, | |
make any modifications you might want to it regarding resolution and | |
output it directly to a STL file. >> Now STL is the PDF of 3D printing, | |
right? >> That's right. >> Other programs besides Fusion | |
360 such as Tinker CAD or Google Sketch Up, for example, | |
will also produce STL files. >> That's right. And that's the output when you take that | |
STL, and the next step is to prepare that in a 3D, it's called a slicing program, | |
which prepares the file for printing. >> That's right. >> The reason we do that | |
is because these programs, even though Fusion 360 was designed with | |
3D printers in mind but these programs are creating 2D images that are not ready | |
for actual three dimensional printing. In essence, what they're lacking is the command instructions that tell | |
the printer, the print head, where to go. >> Right. >> How do we take that STL file and | |
put that into the slicing program? >> Sure. Each 3D printer comes with its own slicing | |
software, so the Ultimaker specifically, uses a software called Cura, and | |
we can open Cura by clicking this icon. >> You can download Cura for free? >> That's right. Slicing is the essential step between | |
your 3D part file and a 3D printed file. What slicing software does is it | |
takes the part file you have, and it will cut it into | |
a large number of layers. You can imagine taking a slice with | |
a chef's knife of your 3D part. >> Okay. >> On each of those layers, it will trace | |
the path that this end effector takes to draw the part on each layer. By successfully drawing each layer, | |
eventually, the printer will print the part. This is basically making the recipe or | |
cookbook for this particular print file. >> Okay. | |
That's a great description. >> We can open the airplane file and | |
it places it on the build plate, the area on the bottom is | |
called the build plate. As long as your file | |
fits within these bounds, it should be able to | |
print by the Ultimaker. When the object is imported, | |
it might have the wrong orientation, we can change the orientation by selecting | |
the object and clicking the rotate button. There's a lot of customization | |
when using Cura. One thing you might | |
note right off the bat, is it shows the amount of time that | |
it will take to print the part. >> Okay. >> What's important here is if | |
you adjust the, say resolution, make it higher fidelity, | |
it will increase the time. But you can do certain things such as | |
increasing the amount of material inside the part, so adding an infill, | |
making it partly hollow, and this will decrease the time | |
it takes to print. You can adjust the settings based on | |
what you need to get a print that's reasonable in time. Another thing we can do is change | |
the size of the object we want to print. If you click the object, | |
there is a scale button. Right now, we have 100% scale, | |
so it's one. If we resize the object to say half scale, we will notice that the time is | |
significantly reduced for print. >> Danny, while this is working, | |
what are some of the main considerations that someone has to keep in | |
mind when engaged in this slicing process? What are the typical things that are | |
adjusted besides the size of the design? >> The number one thing I | |
would consider is whether or not your product needs support material. For example, this airplane has wings and | |
you can see that these wings are not touching the plate, so | |
the 3D printer can't print in thin air. In order for | |
it to actually make this part, you have to include some material | |
under it so that it can print on top. What the printer actually does is instead | |
of creating a solid support structure, it makes a very loosely meshed support | |
structure so that it's easy to peel off. >> I just take that off | |
with some pliers or a file. >> Right. In the basic tab, you can see that | |
there's an option for support type and you can put support structure | |
wherever you want and whatever form. >> Where would you put the support for | |
something like this? >> For this, | |
I would put supports everywhere, since there are a lot of locations that | |
have some overhang or floating material. >> With 3D printing, | |
we can make object completely solid or completely hollow, or anything in between. Should we talk a bit about that infill? >> Since this a display piece and nothing structural, we can actually | |
remove a lot of the material inside. Inside the basic menu, | |
there's an option for fill density. Right now, it starts at ten for default, that means 10% of this | |
object will be filled with material. >> So 90% of it will be hollow. >> That's right. We can change the setting to speed up or | |
slow down the print, depending on what your need is. As I mentioned, since it's only aesthetic, we can drop this down to 5% and | |
print it that way. >> It sounds like the infill consideration | |
is influenced by two factors. One, the amount of time that you have. >> Right. | |
>> If you're pressed for time, perhaps you make an object | |
a bit more hollow. >> Right. | |
>> And second is what you plan | |
to do with the object. >> Right. | |
>> Is it just sitting on your desktop and people are looking at it, | |
then it can basically be a hollow object. >> Right. | |
>> Versus if it's a bracket that's holding something heavy, you may want something | |
that is a bit more solid inside. >> That's right. >> Are there other considerations? How about actually you mentioned | |
the resolution of the print? >> Sure, | |
one way you can change the quality of the print is through | |
the basic menu again. You have several options, | |
the first of which is the layer height and that's going to describe the amount the | |
print head moves up between each layer. >> Okay. >> If you decrease this height, you'll | |
get a higher resolution on the z-axis. >> What's the typical resolution level? >> That depends on the type of printer. >> Typically, in the MakerLab, we print most of our objects at | |
a layer height of around 250 microns. What that means is that four | |
layers equals one millimeter, or in other words, each layer's only | |
a quarter of a millimeter thick. As a point of reference, the width of | |
a sheet of paper is about 100 microns. The UItimaker, as well as the Makerbot, will print something as fine | |
as a width sheet of paper. But typically, we don't do that because | |
the parts that we use look pretty good actually at 250 microns and | |
we don't want to stick around for days to have the object print. Anything else we need to do, Danny, before | |
we actually start the printing process? >> No, at this point, we can go ahead and | |
select this button to save the tool path. It'll actually save it directly | |
to our SD card, in which case, we can use that to print it. >> It's saved, and you're going to | |
take the card and do what with it? >> Once we have the part on the card, we | |
can take it and plug it into the printer, in which case, the printer's going to read | |
the part from the card and begin printing. >> Both the Ultimaker as well | |
as the MakerBot use an SD card to read the file to print. >> That's right. [MUSIC] Here's our jet airplane. Nice job, Danny. >> Thank you. | |
>> It looks great. >> What we're going to have to do is | |
remove this airplane from the platform and remove the support material. What we'll have left is | |
the fighter jet on its own. >> Here it is, Danny. What do you think? | |
>> I think it looks good. >> Great job. Danny just took us through the steps on | |
how you can turn your ideas into objects using 3D printing technology, | |
in this case, to make a plastic airplane. In other parts of this course, | |
you'll see lots of other examples of people using this technology to | |
revolutionize the economy, all the way from making 3D printed earbuds to making | |
prosthetics for children around the world. Hope you stick around | |
to see these videos and learn more about this | |
fascinating new technology. [MUSIC] [SOUND] |