Glossary · Setting

3D printing

Z offset

How far the nozzle is above the print plate at the start. If this distance is wrong, the first layer adheres poorly.

Explained in more detail

The offset between the trigger point of the bed sensor and the actual zero height of the nozzle. The first layer should be slightly squashed, with the lines touching without gaps. Too high: round, loose lines and poor adhesion. Too low: the nozzle scrapes, hardly any material comes out, elephant's foot. Adjust in steps of 0.01 to 0.02 mm. Many current printers measure the Z offset automatically with a load cell or pressure sensor.

Where does the term come from?

Z denotes the vertical axis in the printer's coordinate system, X and Y the plane. Offset means a shift: the value moves the zero height of the nozzle by a fixed amount.

In practice

• The easiest way is to set the value during the first layer; many printers offer a live adjustment (babystepping) for this.
• Whether a smaller or a negative value brings the nozzle closer to the bed depends on the firmware. Check the direction on the first layer.
• A good test: a single-layer square. The surface should be closed and smooth, without grooves and without gaps between the lines.
• After changing the nozzle or using a build plate of a different thickness, recheck or remeasure the Z offset.
• A sheet of paper (about 0.1 mm) is only a rough starting value; you do the fine adjustment on the print itself.

Not to be confused

The Z offset shifts the entire height evenly. If the first layer is too thin or too thick only in some places, the cause is the levelling, not the Z offset.

Frequently asked questions

How high should the Z offset be?

There is no universal value; it depends on the sensor and the printer. What matters is the result: the first layer should be slightly squashed flat, and the lines touch without gaps.

How can I tell that the nozzle is too close to the bed?

The first layer is very thin or translucent, the nozzle scrapes grooves into it, or hardly any material comes out. On the finished part this often shows up as elephant's foot.