Glossary · Design

3D printing

Delta printer

A 3D printer in which the print head hangs from three arms that travel up and down on vertical columns. Very fast, but rare.

Explained in more detail

Three carriages on vertical columns move the print head via parallelogram arms. The position in X, Y and Z results from the interplay of all three. Round build volume, very low moving mass and therefore high speeds. Drawbacks: complex calibration and lower accuracy at the edge of the build volume. Rare among hobbyists, occasional in the professional sector, for example on high-temperature printers.

Where does the term come from?

Named after the Greek letter delta (Δ), because the three columns are arranged in a triangle. The kinematics come from the delta robot, which Reymond Clavel developed in the 1980s at EPFL in Lausanne for fast picking and sorting.

In practice

• The build volume is round and usually considerably taller than it is wide. For large, flat parts the diameter matters, not the height.
• Delta printers usually use a Bowden extruder to keep the head light. Soft TPU is difficult with it.
• If the first layer becomes thicker or thinner towards the edge, the delta radius or arm length in the firmware is usually wrong.
• The ball joints of the arms must have no play, as play there shows directly on the surface.

Frequently asked questions

Why are there so few delta printers?

CoreXY printers reach similar speeds today, have a square build volume and are easier to calibrate. Deltas remain interesting mainly for tall, round parts such as vases.

How do you calibrate a delta printer?

The firmware needs the exact position of the three towers, the arm length and the delta radius. Marlin and Klipper offer automatic delta calibration with a probe, and without a probe you measure at several points by hand.