*Note about Makerbot: This product is a derivative of the Reprap, a project that has been researching ways to make self-replicating machines. I can download a manual to print half the plastic parts from my friend’s Reprap, then go to the hardware store/internet for the other half. Whole machine can be $500. But Makerbot and Reprap are two separate undertakings run by separate people. Both are open source, Makerbot just made its own version and sells it. The machine Reprap originally produced can be viewed here.
On the photos. From this collection alone you can see the range of what some printers can do.
Repraps and Makerbots use a more basic technique called additive layering. In this case a precise plastic melting head, called an extruder, is moved by small gears and motors (It could also be a moving platform with stationary extruder head, but it is easier if I imagine the head). The movements of the head are given by computer and are specific to the thing I am building.
The flyswatter was made on a Makerbot. The striations inside the body of the fly are created by a .50mm nozzle that moved up and down the shape creating the striped look. Along with the movement commands, the extruder is told where to melt the plastic and where to leave empty spaces.
That’s pretty complex in my mind, but an even more advanced method called selective laser sintering can create high levels of detail, like shapes in the second two photos.
Before I really explain what it does, keep in mind the method of layering . When creating the bunny on the makerbot the computer decided to build from the very bottom up. It makes sense this way since the ears have to sit on top of the head and so on.
This limits the Makerbot to layering the plastic on top of the previous layer of plastic (for the most part).The ring could not be printed on a Makerbot because the plastic being melted out to form the web would just fall to the platform.
Selective Laser Sintering, or SLS, layers supportive material as it builds. Take this analogy. I have a glass box in which I need to build a tower of marbles. I try to stack the marbles but they fall. To stack the marbles into a tower I can use sand. Put the first layer of marbles into position, then fill the box with sand to cover that layer over. This creates a new platform on which to build the next layers.
SLS uses this to a much more precise and microscopic degree. These layers are a tenth of a millimeter and the sand is really a fine powder. It is still contained in a box and the machine lays the powder before each layer of material.
Imagine what you can do if you are not limited by the type of material… More on that.