ALL3DP, the resource magazine dedicated to "All About 3D Printing" provided a break-down of the different desktop 3D types available, and their strengths, in the article, "Know your FDM 3D Printers: Cartesian, Delta, Polar, and Scara."
"Desktop 3D printers come in many shapes and sizes. Learn to tell the difference between a Cartesian and a Delta, and everything in between."
The Polar 3D Printer Review:
Polar 3D printers, an emerging design that shows a great deal of promise.
This category uses a polar coordinate system. It’s similar to the Cartesian, except that the coordinate sets describe points on a circular grid rather than a square.
All of which means that you can have a printer with a spinning bed, plus a print head that can move up, down, left and right.
The big advantage is that the printer can function with only two stepper motors. Compare this to a typical Cartesian printer that requires a minimum of one stepper motor for each axis — usually, at least, four — and you begin to see the efficiency savings.
Moreover, Polar printers can have a greater build volume within a smaller space, lacking the requirement of a XYZ framework to move around.
The motion is quite hypnotic to watch. It may not seem as, er, intuitive as other designs, but the end results are exactly the same.
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