Ghosting (Ringing): Ripples After Corners on Your Prints

If you see a faint echo on the side of a part right after a corner, a letter or a hole, that mark comes from the printer's vibration. When the toolhead or bed changes direction suddenly it shakes for a while, and the nozzle keeps printing the wall in the meantime. This is called ghosting or ringing. The biggest factors are speed, acceleration and loose parts.

Symptoms

• After a corner, ripples on the wall that fade out over a few millimeters.
• A faint "shadow" of letters or holes on the surface.
• The ripples are usually on one axis, stronger in the direction of movement.

If the ripples are regular horizontal bands along the height of the part, it may be not ghosting but Z banding.

What causes it?

The toolhead changes direction instantly at every corner. The moving mass (the toolhead or the bed) oscillates like a spring after this sudden change. The oscillation continues for a few millimeters, and because the nozzle keeps printing the wall during that time, the vibration is printed into the surface. The oscillation grows as speed and acceleration rise, as the mass gets heavier and as the printer flexes more.

1. Lower speed and acceleration

This is the fastest and most reliable fix.

• Lower the outer wall speed. 30–50 mm/s gives a clean surface on most moving-bed printers.
• Lower the acceleration. Try 1000–1500 mm/s² instead of, say, 3000 mm/s².
• In Marlin, lowering jerk (or junction deviation in newer versions) softens corner transitions.

In slicers you can set an acceleration limit for the outer wall only. That way the inner parts print fast and the visible surface prints slowly.

2. Check the belts

A loose belt acts like a spring and increases vibration.

• Belts should show slight resistance when pressed with a finger.
• A belt that is too tight also strains the bearings. Medium tension is ideal.
• On CoreXY printers it matters that both belts have equal tension.

3. Tighten loose parts

• Check the screws on the toolhead carriage.
• On printers with V-slot wheels, tighten the eccentric nuts until there is no play in the wheels.
• Make sure the frame screws are tight and the frame is square.
• On printers with linear rails, check that the carriages have no play.

4. Put the printer on a solid surface

A light table or a wobbly stand increases vibration.

• Put the printer on a heavy, stable table.
• Some people put a heavy concrete or marble slab and vibration-damping feet under the printer. This makes a difference especially on fast printers.

5. Reduce the moving mass

• A heavy camera, fan duct or accessories added to the toolhead later increase the mass.
• On moving-bed printers, using a thin spring steel plate instead of a glass bed reduces the mass of the bed.

6. Use input shaping

Input shaping is a software feature that knows certain vibration frequencies of the printer and shapes the motion commands so that they cancel this vibration. It is the most effective modern fix for ghosting.

• Klipper: The firmware where input shaping is most widely used. Vibration frequencies are measured with an accelerometer (such as an ADXL345) and the settings are calculated automatically. Without an accelerometer you can tune it by hand with a test print.
• Marlin 2.1 and later: Has input shaping support. The frequencies are found with a test print.
• Bambu Lab and similar newer printers: Mostly do vibration calibration themselves. Repeat this calibration after the printer has been moved.

With input shaping you can get a clean surface even at high speeds. But it does not fix mechanical problems (a loose belt, a wobbling wheel), so fix those first.

7. Measure with a test print

After changing settings, print a ghosting test model. These are usually a thin wall or cube with a letter or sharp corner on it. Compare different speed or acceleration values on the same model.

Order of fixes

Frequently asked questions

Does ghosting affect the strength of the part?

No, it affects only the appearance. Other problems that affect strength, such as layer separation, have different causes.

I do not want to lower the speed. Is there another way?

Input shaping and a solid mechanical build are the way to reduce ghosting without lowering speed. If you lower the speed only on the outer wall, total print time grows very little.