Movement and Styles

Motion Control - X, Y, Z Axis:

Cartesian printers move one or two motors along each of the X, Y, and Z axes and the name was derived from the Cartesian coordinates system. They typically have a rectangular build area and the printers themselves tend to have a cube-like shape. The Lulzbot Mini is a fine example of these types of printers.
Delta printers have three arms that come together in the center to suspend the extruder above the build area. Deltas also use a Cartesian coordinates system to move around in, but instead of moving one motor per axis at a time, all three arms move at different rates or times to precisely move the nozzle with triangulation. The SeeMeCNC Rostock MAX V2 is a prime example of a delta printer.

These are usually used on the printer’s Z axis. They rotate, thus forcing nuts to move up and down. Inexpensive printers will use simple threaded steel rods, which are essentially extra long bolts. Higher quality printers have smooth chrome plated leadscrews designed to minimize backlash.

Lead Screw

Belts move things. The X and Y motors have sprockets that drive the belts. Most printers also have some way of adjusting the tension on the belts.

Belt

Unlike regular DC motors, which rotate continuously when given power, stepper motors rotate in increments. This gives them precise control over their position. Most printers use NEMA 17 type motors with 200 increments (steps) per revolution.

Stepper Motor

The frame holds everything together. Early printers had frames made out of lasercut plywood. Printers now have frames made of sheet metal, aluminium beams, or plastic. Many parts of the frame are often 3D printed themselves. The more rigid the frame, the more precise the printer’s movement will be.

Enclosures for 3D printing are used for safety. There are moving parts and heating elements that users will want to protect themselves from. If you printer does not offer an enclosure it is easy to construct your own. Something as simple as a cardboard box could suffice.

This takes the 120V AC electricity from the wall and converts it to low voltage DC power for your printer to use
ATX Power Supplies- These are the same power supplies used in desktop computers. They have been repurposed for use in many printers. They are very beefy and efficient, and have separate lines that provide power at a variety of voltage (12V, 5V, 3.3V).
Voltage - some machines run 12 volt systems, while others run 24 volt systems. This becomes critical if you are going to replace components - especially your heater cartridge or hotend. Make sure you order the appropriate parts.

The motherboard is the brain of the printer. It takes the commands given to it by your computer (in the form of G-Code) and orchestrates their execution. The motherboard contains a microcontroller (essentially a tiny, self contained computer) and all the circuitry needed for running the motors, reading the sensors, and talking to your computer. Here is a comparison of the different motherboards we carry.

Motherboard

These chips are responsible for running the stepper motors. They fire the coils of the motor in sequence, causing it to move in increments. Many motherboards have the stepper drivers built in, but some also have them in modules that can be unplugged. By balancing the power fed to each coil, the driver is also able to divide steps up into further increments. This is called microstepping, and allows more precise control over the motor than is normally possible. The stepper driver also controls how much electrical current is fed to the motor. More power makes the motor stronger, but also makes it run hotter.

A set of stepper motor drivers

Some printers have an LCD screen so they can be controlled directly without hooking them up to a computer. These can be basic black and white displays like the VIKI 2 or advanced wifi enabled touchscreens

MatterControl T10

Some printers also have an SD card slot from which they can load G-Code files. This allows them to run independently without a computer.

The endstops are how the printer knows where it is. They are little switches that get pushed whenever an axis moves to the end. This is how the printer finds it’s starting point before printing. Most printers use mechanical switches, but some are known to use optical sensors.

Many printers have some kind of a system for automatically making sure that the bed is level with the nozzle. Some do not, though, and must be calibrated by hand. MatterControl also has the ability to account for unlevelness in software.