So, 3D printing is gaining popularity in all industries as it's one of the most reliable forms of computer-assisted manufacturing. Now, computer-assisted manufacturing is called CAMP, and it's used in almost every industry for production in one way or another. Let's take a look at the different manufacturing methods of CAM. Overall, we use three main ones: formative, subtractive, and additive manufacturing processes. Let's take a look at each one separately. Formative manufacturing refers to the practice of taking some material, say a sheet of metal, and then using incremental formation processes to reshape that material into your final product. Think about this as casting and stamping metal sheets, for example; they're great examples of how we use formative manufacturing techniques. Let's take a look at this video using stamping dies. We can see that we've got a sheet of metal on a production line, and it's changing shape incrementally over time until we get to our final product. This is a full production line that eventually gets to the final state.

Subtractive manufacturing, which was the second one we talked about, refers to successively removing excess material from a solid block of material. Think of this as laser cutting or CNC machining like milling or lathing, for example, and they operate on the premise of taking material away from a block to get your final product. Let's take a look at how that might work. I've got a video here of a laser cut we'll take a look at. We can see that this guy is just printing out some really simple words onto some plywood. He's using that laser to burn out a very precise shape. Just as quick as that, we can actually produce something. Now, the problem with that is obviously using a whole sheet of wood there. You've popped out the part that you need, but you've got all that excess waste material. Unless you're using perfectly tessellating objects, it's probably not going to be the most environmentally safe way to do that for sure.

The technology that we're interested in, which is 3D printing, is fused deposition modeling. It's actually the additive manufacturing technology that we were talking about. The core idea behind additive manufacturing techniques is that you essentially are building up your object from nothing. Remember, formative was to take something, bend it, whatever, make it into what you need. Subtractive was to take something, cut parts away until you get what you need. Additive is to take nothing, add stuff together to form what you need. Let's take a look at the principle of that. I've got this thermal image of a 3D printer at work. We'll just watch how the reddest parts are the hottest parts of this, and we'll see that it's laying down plastic on top of itself. You can see over time, it might only be 0.2 of a millimetre that that's building up, but over time it will get to a point where you've got a full model.

That's particularly interesting for us looking at hobbyists, inventors, and makers. What we can do is actually print customized models without the additional costs of the full setup of, say, a laser cutter, all the materials, and stuff. Especially for 3D printing, you've got very cheap material. The plastic that we use to print with is actually quite inexpensive when you compare it to, say, big sheets of acrylic or something like that. Secondly, you have the ability to print geometries and shapes that aren't possible with laser cutting or formative manufacturing. You've got very high limitations with that technology. There are some limitations with 3D printing, but this falls into a very good space for customized models. Finally, there's no waste really of additive manufacturing processes except for the old prints that maybe didn't print just how you wanted them. So that's sort of the lowdown on the type of manufacturing process that 3D printing is, and it'll give you a good idea of some intuitive ways of thinking about 3D printing, knowing that it's building something up from nothing.