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/02_module-1-what-is-3d-printing
/03_3d-printing-facts-concepts
/03_materials-costs.en.txt
[MUSIC] Now, let's take a look at the materials | |
that are used to create 3D printed objects. Although there are many different | |
types of 3D technologies, nearly all 3D printers | |
work in one of two ways. They either take a soft material and | |
make it hard, or take a hard material and make it soft. Thus, just about any material that can be | |
hardened or softened can be 3D printed, including plastic, metal, | |
carbon fiber and even chocolate. At present, the vast majority of desktop | |
3D printers are FDM machines such as the Ultimaker, that create objects | |
by softening a strand of thermoplastic. There are currently two major types | |
of thermoplastics, ABS and PLA. ABS stands for | |
acrylonitrile butadiene styrene or something like that, and | |
is made from petroleum. The second type of thermoplastic is | |
PLA which stands for polylactic acid. This is made from corn. Both ABS and PLA are very strong and | |
share a number of properties. For example, they have the same melting | |
point, come in a variety of colors, and both are used by large manufacturers | |
to make a variety of products. For example, if you've brought Legos, | |
Legos have been made with ABS plastic. Our 3D printing and hardware course will | |
dive into more details about the pros and cons of each of these | |
different types of plastics. Of the two, we recommend PLA. This is the material that we use for | |
nearly all of our printing. And when you melt it, | |
it actually smells like waffles, so has a pleasant side effect. One of the limitations of both ABS and | |
PLA is their stiffness. Both are quite hard and don't bend easily. For example, | |
this smartphone case was made using PLA. As you can see, it's not very flexible. So in recent years, a variety of different types of flexible | |
plastic filaments have emerged. In fact, I have one right here. Here in white, | |
this is a flexible filament. And as you can see, it bends quite easily. So this sort of material is really good | |
for making things that need to flex, such as a shoe or a ball. In addition to hard and soft plastics, | |
a number of mixed polymer materials are starting to appear, | |
such as this wood-based polymer. This gnome is printed in a polymer that | |
is 60% plastic and 40% wood byproduct. And as it melts, | |
the plastic is melted away and you're left with the wooden product. In addition, there is concrete polymers | |
and polymers that look like bronze. The range of materials that can be heated | |
up and melted through an FDM printer, such as this, will continue to | |
increase in the coming years. So the capabilities of the machines | |
will be quickly expanding. One of the frequent questions that | |
those new to 3D printing often ask is, how much does this material cost? Well, what would you think that | |
a roll of PLA or ABS would cost? This is a kilogram. Well, in actuality, the cost of this material is much | |
cheaper than most people think. A kilogram of thermoplastic typically runs | |
for about $20 US, which is $0.02 a gram. As a point of reference, | |
a typical smartphone case such as the one I have here, | |
weighs between 20 to 25 grams. Thus, you can print a case for | |
your phone for less than $0.50, which is a lot less than you | |
would pay if you bought one. Thus, 3D printing objects is typically a | |
lot cheaper than buying them from a store. [MUSIC] [SOUND] |