Hi. Good morning everybody. How are you today?
I hope you can hear me. I'm in a different room today and my voice kind of echoes.
When I edit, I'll try and use something to reduce the echo if I can.
I hope you can hear it.
Anyway, as usual, don't forget, after you watch this, if you go to my site,
stevenaskew.com, you can download the script for this talk,
and all of my other talks, and you can find some listening questions and sample answers as well.
Please, try. The more you read, write, listen, and speak, the better your English will get.
And, as always, these topics are things that I find interesting, but if you
have anything you'd like me to research and talk about, please put it in the comments
below here. I love learning about stuff so, anything you want, I'll research.
OK, today we're going to talk a little bit about 3D printing. Now, there are two types of 3D printing.
Well, there are many types of 3D printing, but there are two basic types of 3D printing
on the commercial market. The first one, the very basic type, is the layer system. Now,
if I go and print something from a regular printer, a 2D printer, what it does is it
puts a layer of ink onto the piece of paper. Now, 3D printing is exactly the same as that
except on top of the first layer it puts a second layer. So, if I want to 3D print my
head, for example, and who wouldn't? Then what I basically do is I make a design of
my head on a computer, and the design splits it up into thousands of layers, and it just
prints layer on top of layer on top of layer. And, in the end, you get my head.
I might do that later.
Now, that type of printing is called additive manufacturing because it adds.
The ... of course the regular type of manufacturing, subtractive manufacturing,
is what you do in factories where they plastic mold things, and that takes away, of course.
We'll talk about that a bit later. So, the basic type of 3D printing was invented in
the 1980s. It's come a long way since then, of course. Now you can buy a regular 3D printer
and have it in your home. Now, the regular printer you use to print on paper uses ink,
of course. A 3D printer can't use ink. What it does is it uses something called a thermosetting polymer.
Polymer is plastic. Thermosetting, thermo means heat, thermometer. So, what thermosetting
polymers do is they're liquid under heat and then when they cool down they go hard, and
once they've hardened they don't change their shape. So, you can use them very easily to
print things. They become a liquid and then when they hit the air they cool, they harden.
So, of course, when you want to make my head, that's the kind of plastic you want. Now,
a problem with this is it takes a very long time to print something. If you have ever
printed a page ... a colored page using a dot matrix printer, the old-style printer,
it takes a long time to print one page. Now, imagine multiplying that by thousands. It
takes a very long time to print my head. There is a new style of 3D printing coming out called
CLIP. C L I P. CLIP stands for Continuous Liquid Interface Production, a mouthful, I know.
Now, that doesn't use thermosetting polymers, that uses photopolymers. Photo means
light. It comes from the Greek photos. Photograph, for example, graph means picture in Greek,
so photograph is light picture. So, a photo polymer is a plastic that hardens in contact
with light. Now, this makes printing very easy ... very easy ... much easier. What you
do in a CLIP machine is, you have a pool at the bottom full of a liquid photopolymer.
The bottom of the pool is transparent and underneath that you have a U.V. light.
Then, between the polymer ... the photopolymer and the U.V. light you have an oxygen permeable membrane.
Now, this is where it gets very clever. Very very clever. What they do is
they can move the molecules in the oxygen permeable membrane around. Now, an oxygen
mole .. an oxygen molecule can stop, can reflect a U.V. light photon. So, what they do is,
they have their design and they move the oxygen molecules around and where there is an oxygen
molecule the U.V. light cannot penetrate. Where there is no oxygen molecule, where there
is a space, the U.V. light comes through. So, by moving the oxygen molecules around,
they can make very very complex shapes. And this is much faster, because basically the
machine pulls the shape out of the liquid photopolymer pool and the oxygen molecules
move around creating the design as it pulls it up, which is much much faster. It's not
just faster, it's also much much stronger, because your basic 3D printer, your layered
3D printer, if you look at it under a microscope, of course, you have lots of layers. Now, if
you look at it with the naked eye you can't see that, but when you go in close up, these
layers are very very visible. And where there is a layer, of course, there is a weakness.
If you're going to break something, it's usually going to snap at a weak point, and where these
layers are are weak points. The CLIP system doesn't create layers because it prints ... it
molds continuously, so it's much much stronger and it's much much faster. All right. 3D printing.
What are the advantages of 3D printing over regular molding, for example? Well, the most
obvious advantage is, of course, if you can draw it, you can print it. 3D printers can
print almost any shape. Not almost, they can print any shape at all. So, if you can design
it, a 3D printer can make it. And, of course, they can even create bone. If you C.T. scan
a bone, let's say you've got a missing part of your skull, if you can C.T. scan the skull
you can print a piece that fits into that skull exactly. With regular molding you're
going to be close but not exact. With 3D printing and a C.T. scan you can actually make a piece
that fits in exactly. So, if you can draw it, you can print it. Of course, now, the
second advantage is you don't have to change the mold. If you want to make something, say,
for example, this stapler. If you want to plastic mold a stapler what you do is you
make a mold of it. You have your mold made of wood or resin or metal or whatever it is,
and you stick it to your machine. Then, you have a piece of plastic across the top. You
heat the plastic so it becomes soft and then you suck it down by creating a vacuum. That
of course, makes this shape. If you want to make more pieces you have more molds, of course.
Now, let's say you want to go from making this stapler to this stick of glue, what do
you do? Well, you have to, of course, change the mold. You have to stop the machine, you
have to take the mold off, you have to put your new mold on and start again. With a 3D
printer, what do you do? Well, you just change the design. You can print this and then you
can print this. So, it's much much easier. And of course there is less waste. When you're
making something like this, because it's subtractive, which we talked about at the start, when you
suck down your plastic, of course, if you have ten molds, you're going to have spaces
between the mold where the plastic is continuing. So, after you've finished you have to cut
that plastic off, which is waste. I mean you could melt it and use it again but you're
always going to have some waste. With a 3D printer you don't have that. It only prints
plastic where the shape is, so there is no waste. Now, of course, the biggest advantage
with 3D printing is you can have a printer at home. You can print your own models and
the price of printers is coming down day by day. Now, you can buy a printer for about
a hundred dollars. And the last advantage, well, really good advantage of course, is
you can print things in space. How awesome is that? So, let's say you're an astronaut
on the space station and suddenly there's a problem. Your oxygen regenerator has stopped
working. What do you do? You have to replace the part, you don't have the part! Oh no!
What do you do? Well, NASA sends you the designs, the blueprints, you plug them into your 3D
printer. ZZZ ZZZ ZZZ You print the part. And you fix your oxygen machine. So, you can print
things anywhere, which is extremely useful because now you can travel into space without
carrying lots of spare parts, lots of replacements. All you need are the designs, the 3D printer
and the inks, the plastics. So, how do we use 3D printers these days? Well, they were
invented in the 1980s of course. They became more common after about 2000. So, what do
we have now? You can have 3D printed clothes, 3D printed shoes, you can 3D print parts of
engines, you can 3D print whole cars. Airbus 3D printed an entire airplane. You can 3D
print casts for your arm. If you break your arm, you don't have to have the whole plaster
cast, of course. You just need supports here and you can 3D print that. You can 3D print
food, you can 3D print chocolate, you can 3D print bone parts, which I talked about
earlier, a piece of your skull. You can 3D print human organs. There is a girl in America,
I think, who was born without a nose and what they did is they 3D printed a layer of cells
to put on, and the cells slowly grew and became a nose. They've 3D printed ears. They've actually
3D printed a human liver. In 2013, they made a human liver. I mean, it's not ready to go
into a human yet, but they can use it for drug trials and things like that. Human organs
became possible in about 2003. And how it works is, this is really interesting, basically
the same as with plastics except instead of printing ink it prints cells. So, it has a
3D matrix and it puts cells into that matrix. And of course, how are you made up? You're
just made up of basically cells, lots and lots of cells together. So, you can recreate
something by recreating those cells. Now, the amazing thing is the possibilities of
this are endless because, if you can 3D print human body parts, you can do it with that
person's cells. For example, they can take cells from me, they can clone them, and they
could print me a liver. Well, in the near future, they will be able to print me a liver.
Now, what is the good thing about that? Right now, if you have a liver transplant, or a
heart transplant, or any kind of transplant, your body tries to reject it. Our bodies are
set up so that we try and reject any foreign body inside them. That's why when you get
the influenza virus inside you, you get really sick, it's your body trying to burn off that
virus, kill that virus. When you have a liver inside you, your body is going into overdrive
trying to get that liver, that foreign body, out of you. So, to stop that, for the rest
of your life you have to take immunosuppressants. Those are drugs that suppress your immune
system. The immune system is the part of you that tries to get rid of foreign bodies. If
the new liver is made from your cells, you don't need those, because your body doesn't
recognize it as a foreign object. It's part of you. Isn't that awesome? And of course,
if we can print body parts, we don't need donors. Right now, there is a huge shortage
of kidney donors, liver donors, heart donors. There are more people waiting for them than
there are people supplying them. And of course, if you want to supply a kidney you have two,
you have one to spare, but if you want to supply, if you want to donate a liver, or
a heart, you have to be dead. Which is quite sad. Obviously. So, if we can print body parts,
if we can print human organs, the possibilities are incredible. Although, of course, we have
to be careful that it doesn't become body parts for the rich, because we have to make
it fair, we have to make it affordable for everybody. Because if only rich people can
afford these new human organs then that's not a fair system. OK. Let's look at a couple
of problems associated with 3D printing. Well, of course forgery is a big one. Right now,
you have a lot of cases of forgery in the world. People can forge paintings, you can
paint paintings, but an expert can tell it's not the real thing. But, if you can scan,
let's say Van Gogh's Sunflowers, if I can get access to it and if I can scan it using
a 3D scanner, then I can recreate that picture exactly. Down to the splinters in the wooden
frame, the labels on the back, the brush strokes. I can create that ... I can recreate that
almost exactly. And if that becomes possible, what happens then? How do we protect copyright?
And of course, the second thing's in the news a lot recently. You can 3D Print guns of course.
If you google it, you can find the blueprints for a 3D printed gun online. If you can make
your own guns, how do we control them? Well, America doesn't really try and control its
guns anyway, so that doesn't really matter but, if you can print a gun at will, what's
going to happen? So, there's a couple of problems. However, the potential for 3D printing far
outweighs the problems, in my mind. For example, we talked about human organs. That could be
a huge lifesaver. But, what about being able to create food? If we can put human cells
in a matrix, then of course, we can put animal cells in the same way. We can create our own
meat. Just think about what that will do to the world. Right now, growing cows, what harm
does it have to the Earth? Well, deforestation. We cut down the Brazilian rain forests to
make pasture land. Global warming. The methane released from the cows, the cut down trees.
The water waste. How much water does it cost to raise cows? And of course, the cruelty
to animals. We raise these animals and then we kill them. If you can 3D print food, all
that is gone. And then of course, accessibility. Amazon has made shopping much more accessible.
You now don't have to leave your home. You can order, buy, and receive stuff without
even leaving your home. Once you have a 3D printer, we may not even need shops anymore.
You don't have to go to the supermarket to buy your food, you print it. You don't have
to go out to town to buy your clothes, you just print them. And they would fit your body
exactly because they would be made from scans of your body. They wouldn't be rough, they
wouldn't give you blisters, your shoes wouldn't hurt you, they would be exactly printed to
your specifications. So, what would happen to shops? That's an interesting question.
Possibly shops would end up being online places that sell designs, that sell blueprints, and
sell the inks, the plastics, the materials that are needed to do these things. That's
going to be very very interesting. Anyway, because technology is speeding up, because
advances are coming much much faster, this 3D printing is going to take off big time
very very soon. It's very exciting and a little bit scary. I wonder what will happen. Anyway,
thanks for watching. As always, don't forget, go to my site. You can find the script for
this and you can find some listening questions, you can practice writing, things like that.
And if you like listening to English, if you like learning something in English, if you
want to practice your listening skills more, if you want to improve your listening skills,
then please don't forget to subscribe. Anyway, thanks for listening. Talk to you next time.
Bye.
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