The simple 3D printers used by most hobbyists fall into one of two categories: "bed slingers" or "bed droppers." The names refer to the way the printer handles movement in three dimensions for printing an object. Both methods work well, but there are differences that may cause a person to choose one instead of the other.
Bed Slinger Printers
Prusa i3 "bed slinger"
3D printer
This type of printer has a printer head that is anchored to a horizontal arm attached one or two fixed uprights (usually two). The print head moves along the X-axis—left and right—and the horizontal arm and print head move in the Z-axis—up and down. Movement in the Y-axis is handled by the printer bed moving forward and backward. Bed slingers are the most common inexpensive printers. The Prusa i3 and the Creality Ender 3 are well-known examples of the type.
A bed slinger printer can be lightweight and compact. It isn't difficult to find a place for such a small device. Some bed slingers—like the
Bambu Lab A1 mini printer—can easily be tucked away on a shelf or in a corner of a work area. The tradeoff is that these compact printers have small print beds, and large objects have to be printed in multiple pieces and glued together.
Bed Dropper Printers
Zortrax M200 "bed dropper" 3d printer
Bed droppers—as the name implies—use vertical movement of the bed for the Z-axis. The print head stays at the top part of the printer and moves in both the X- and the Y-axes. When the print starts, the print bed is at the top of the printer. As the print progresses, the bed drops to keep the top of the object being printed near the print head. To accomodate the movement of the print head, most bed dropper printers are enclosed in a frame. A common example of the type is the
Creality Ender 5 series of printers.
A big advantage of the bed dropping 3d printer is that the object being printed doesn't move much. This makes it possible to do time-lapse photography or to use a webcam to keep an eye on the model as it prints. The rigid frame also makes bed dropper printers very stable. The drawback of the design is that they tend to be larger and heavier than comparable bed slingers.
