Troubleshoot sculpting

This table lists common sculpting problems and possible solutions:

Problem/Error Message	Possible Solution(s)
Sculpted strokes appear shaky, not smooth.	Shakiness from your hand can make it difficult to sculpt smooth strokes. Turn on the Steady Stroke option to produce a smoother stroke. See Produce smooth tool strokes.
Collapsing edges on a tessellated mesh creates warning messages.	Sometimes edge collapse is denied when you try to reduce a tessellated mesh. This is because dynamic tessellation tries to preserve UV shell borders during its reduction process. If this occurs, delete UVs from your model before working with the Reduce, Refine, or Remesh tools.
The following error appears when subdividing a model: Two or more faces share more than one edge. This model cannot be subdivided until this is corrected.	This indicates a topology issue that can occur during modeling (in a 3D modeling application). For example, if one or more interior edges were deleted, creating some n-sided faces, or if some faces are created sharing more than one edge. The polygons must be corrected in the modeling application, then re-imported to Mudbox so the model can be subdivided.
The Mesh > Add New Subdivision Level > Smooth UVs option does not work when subdividing a model imported from another 3D application. The UVs are not smoothed.	Many 3D applications produce UVs where each face is individual and separate. In these situations, the UVs must be merged before exporting to Mudbox. Otherwise, the UVs cannot be smoothed when the mesh is subdivided.
The cursor outline indicating the radius for the sculpt or paint tool disappears.	The outline for the tool cursor only appears when the tool is over the model in the 3D View. Position the cursor over the model to view it. The Radius property is set too large and the outline appears outside of the current 3D View. This can occur when setting the Radius using the B hotkey if the tool cursor is off the model. See Sculpt Tool properties.
No stroke appears when sculpting on a model.	The resolution of the model is too coarse in comparison to the size of the current sculpt tool. Add more subdivision levels to increase the model’s resolution or increase the radius of the tool. The sculpt tool Strength property is set too low for the sculpt tool. Increase the Strength. If using sculpt layers, ensure the Strength setting for the current layer is not set too low or to zero. See Sculpt Tool properties.
Two sculpt tool cursors appear on the surface of the model.	The Mirror property for the tool is on. If you don’t want to sculpt symmetrically, turn Mirror off. See Sculpt Tool properties.
Sculpting causes large spike effects to appear on the model.	The Strength property of the current sculpt tool is set too high in relation to the tool radius. Undo your stroke (Ctrl + Z) and reduce the Strength property for the sculpt tool. See Sculpt Tool properties.
Symmetry property has no effect when sculpting.	An incorrect mirror axis is specified. Check the mirror axis property and reset as required. If the model was moved off the XYZ origin, some mirror axis properties will not work. Use the Local or Tangent mirror properties in these situations. See Sculpt using tool symmetry.
The error Symmetry not found appears on the Status Line when setting a topological axis using Edit > Set Topological Axis.	The tool cannot determine topological symmetry based on the current face selection. Select the faces and set the axis again, ensuring you select the faces at the lowest subdivision level. If Mudbox continues to indicate a lack of symmetry, the model is likely not topologically symmetrical. See Sculpt using symmetry.
A semi-transparent 2D image appears in front of the model in the 3D View.	You may have a stencil image selected for the camera view. In the Stencil tray, click the Off button.
Cannot undo sculpting performed on another subdivision level after switching levels.	The Undo history is not saved when switching between subdivision levels. You can only undo sculpting on the current subdivision level.
Grab tool creates "spikes" when using Dynamic Tessellation.	Spikes often occur when you use the Grab Tool with Tessellation enabled, with Follow Path turned on. If this occurs, use the Smooth Tool with a high Collapse Threshold value in the Tessellation settings. This will shrink the spike down. You can also bulk up the volume of your mesh with the Bulge tool.
Sculpting performance decreases at higher subdivision levels.	Sculpting at higher subdivision levels (when many vertices are modified by a particular sized brush) requires more RAM than lower subdivision levels (using the same sized brush) because fewer vertices are affected. In general, make changes that affect larger regions of a surface at a lower subdivision level. Fewer vertices are moved, so sculpt performance improves.

Tip: In general, many issues in Mudbox can be resolved by deleting your user settings in order to refresh all tools and options to their default values. See Remove your Mudbox user preferences.