Loose belts
9 usi3d guides for “Loose belts”, each with the likely causes, how to check which one is yours and the step-by-step fix, with each manufacturer's official sources.
3 apply to any FDM printer and 6 are for Bambu Lab, Creality, Elegoo and Voron printers.
Each guide summarises the official documentation and says whether usi3d has already verified it on a machine.
Any FDM printer (3 guides)
- Loose pulleys or grub screws: shifted layers, play and noises in the axes
Layers shift like a staircase in X or Y, you feel play when moving the toolhead or the bed with the motor still, the belt runs crooked or an axis makes a strange noise…
- Loose, over-tight or damaged belts: how to check and tension them
Echoes or ripples appear next to edges (ghosting), circles come out oval, or layers shift.
- Replacing a worn or broken belt and tensioning it properly
The belt has broken teeth, cracks or frayed edges, or it has snapped; or, even after tensioning it, the layer shifts or the noises when the axis moves come back.
Bambu Lab (1 guide)
- Tensioning the belts on the X1, P1, A1 and H2D (oval circles, ringing or tension alert)
Circles come out oval, ringing or dimensional errors appear, the printer warns after calibration that a belt needs tensioning (the A1 asks through an HMS alert) or it…
Creality (2 guides)
- Ender 3 V3 KE: the vibration sensor is not recognised, the screen flickers or ringing appears (input shaping)
When you connect the vibration compensation sensor (G-sensor) to the Ender 3 V3 KE for input shaping, the screen says no sensor is recognised or starts flickering; or…
- Ender 3 V3 SE: noise or stuttering on the X or Y axis, from a motor or from a fan
The Ender 3 V3 SE makes an odd noise when the X or Y axis moves, a motor makes noise while printing, an axis stutters at one spot (sometimes with a noise) or a fan does…
Elegoo (2 guides)
- Centauri Carbon 2: unusual noise or vibration when printing, moving or homing
The Centauri Carbon 2 makes an abnormal noise or vibrates while printing, during idle moves or while homing.
- Centauri Carbon: self-test stuck at «Input Shaping» or error 401 (accelerometer)
During the first-use self-test, or when calibrating Input Shaping manually, the Centauri Carbon screen stays stuck on the Input Shaping step and does not continue, or…
Voron (1 guide)
- Voron Trident and 2.4: A/B belts loose, too tight or uneven
On a Voron Trident or 2.4 (CoreXY), the A and B belts have lost tension, are too tight or have different tensions.
Products that may help
Products from the usi3d shop that fit these guides, chosen for the fit and not for the commission. Check that they work with your printer before buying.
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