What Z hop changes — and what it does not
When the nozzle never rises on a travel move, the first question is not the hop height — it is whether a hop was planned at all. Orca Slicer ties the lift to retraction: on a travel that triggers a retraction, the Z Hop group can raise the nozzle to create clearance over the print, then lower it before extrusion resumes. That clearance is the whole job: it changes neither how much filament is pulled back nor where the first layer sits.
- Z hop changes vertical clearance during a retracting travel move, and only while the toolhead is not extruding.
- Retraction pulls filament back to limit oozing. Retraction length and speed can reduce stringing, but stringing can also come from temperature, moisture or the material itself, so treat them as one lever rather than the cure.
- First-layer Z offset sets the nozzle gap above the plate and shifts the whole Z frame; for first-layer problems, start with the practical Z offset workflow.
The Z Hop group sits under Printer Settings > Extruder; some controls are Advanced and labels move between versions, so read the fields in your own build. The variables are z_hop (height), z_hop_types (Auto Lift, Normal Lift, Slope Lift, Spiral Lift), travel_slope (the angle for Slope and Spiral; 90° behaves like Normal Lift), retract_lift_above and retract_lift_below (positive values restrict lifting to a window of absolute print Z), and retract_lift_enforce (All Surfaces, Top Only, Bottom Only, Top and Bottom). The Z Hop reference documents the current controls; it is current documentation, not a guaranteed description of every installed version, so compare it with the field names your build actually shows.
Check these in order when the nozzle does not lift
Work down this list before changing a number; more than one of these can keep the lift out of the file, and raising the height first hides the cause.
- The build and the preset that actually sliced the file. Confirm the OrcaSlicer version you are running, then inspect the active printer/nozzle preset and any applicable filament retraction or Z-hop override that your installed version exposes. An edit made in a profile that was not selected changes nothing.
- A nonzero height.
z_hopis a float; a zero, or a value that never reached the selected preset, removes the lift silently. - A travel that retracts. The lift accompanies a retraction; if retraction is off, or the travel is shorter than the travel-distance threshold, there is none to lift with.
- The absolute-Z window.
retract_lift_aboveandretract_lift_belowrestrict the lift only when positive, measured against absolute print Z; a window that excludes those layers keeps the hop out of them. - Surface rules.
retract_lift_enforcelimits the lift by surface; Top Only or Bottom Only can look like a broken hop on the surface you are watching. - A fresh slice. Change one field, slice again, and inspect the specific travel moves; an unsliced profile change is not in the file yet.
Reading the lift in the preview and the G-code
Normal Lift is easiest to identify: the nozzle moves straight up during retraction and returns before printing resumes. Slope and Spiral move diagonally, so they are not necessarily separate pure-Z commands; a sloped move can look almost flat in a preview that does not render the angle (at 90°, the slope type behaves like Normal Lift).
Preview rendering depends on the version and settings, so do not assume the view shows every lift; when the picture is ambiguous, export the G-code and read the move sequence around a retraction. A rising XYZ line alone is not proof (it can be the next layer change), so match the Z movement to a retraction and a travel in the same layer.
For stringing or oozing rather than a missing lift, retraction length and speed are one useful input: the retraction tower method measures the shortest clean retraction length on your machine. Temperature, moisture and the material also drive stringing, so keep a hop separate from that question — a taller hop is not a stringing cure, and it is not a first-layer Z offset.
Decision table: symptom to possible explanation
What you see | Possible explanation to check | First move |
|---|---|---|
No vertical movement on any travel | Check whether the lift was scheduled at all: active preset, zero height, no retraction, or an excluded Z window | Confirm the active profile and that the travel retracts |
Appears on upper layers but not low ones | Check the absolute-Z window against the heights where the hop is missing | Compare the window values with those layer heights |
Appears on one surface only | Check whether | Set All Surfaces or match the surface you are checking |
A lift looks diagonal or flat | Check whether Slope or Spiral is active; | Compare with Normal Lift, or set the traveling angle to 90° |
The nozzle still drags with a lift | Check whether something is taller than the layer — a blob, a curled edge, or over-extrusion | Fix the raised material rather than hiding it with a giant hop |
An edit changed nothing | Check whether the edited preset was used and the file was re-sliced | Confirm the active profile, then slice again |
A repeatable check and completion standard
Run the same model and profile twice and record what you actually observe:
Model / profile | Hop configuration | Observed clearance | Strings / scars | Sliced time | Actual print outcome |
|---|---|---|---|---|---|
Before |
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After |
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Leave the observation cells empty and fill them with what you see. Sliced time is the slicer's estimate from the preview; the actual print outcome needs a confirmation print. Do not record an estimated time as a measured result, and do not write a clearance you have not observed.
Increase the hop only enough to address the measured clearance; a taller lift costs time at every retraction and cannot repair a curl or over-extrusion.
Consider the check complete when:
- the preset you edited is the one that sliced the file;
- the travel around a retraction shows the expected Z movement in preview or G-code;
- the travel in question passes the feature without the drag you were seeing;
- the value is saved with the profile that prints the part;
- a confirmation print shows no new stringing or surface scar.
There is no universal hop height: the useful value is the smallest one that clears the measured obstruction. If the surface only misbehaves at higher speed, the hop may not be the limit at all — travel and per-feature speeds have their own ceilings, and OrcaSlicer speed settings explains which to check first.
