How to Prepare a ZBrush Model for 3D Printing

Author: Arndt von Koenigsmarck · Technical review by Paul Gaboury · Last reviewed August 2026 

A model has to be watertight, or "manifold," before it will print reliably, meaning a single closed surface with no holes into its interior and no non-manifold edges. Sculpts built from many pieces, and especially 3D scans, rarely start out that way. This guide covers how to prepare a ZBrush model for 3D printing, from checking and repairing the mesh to cleaning up messy scans. It is part of the wider guide to ZBrush and 3D printing.

Before fixing anything, find out what is wrong. Under Tool > Geometry > Mesh Integrity, click Check Mesh Integrity, then Fix Mesh if prompted. This catches stray vertices, zero-area faces and non-manifold edges, which are the errors most likely to break a print or confuse a slicer.

Open boundaries are the most common problem, and often hard to spot on a detailed sculpt. Two quick fixes handle most cases:

• Close Holes. Tool > Geometry > Modify Topology > Close Holes fills open boundaries in a single click, which is ideal for pinholes and small gaps.

• WeldPoints. Immediately after closing holes, run WeldPoints to fuse coincident vertices, for example where imported or stitched parts meet.

You can also close holes locally with the ZModeler brush > Edge > Close option, which is handy for sealing a specific opening in the surface.

When a model is made of several overlapping SubTools or inserted meshes, you need to combine them into a single closed volume. The most reliable way to do this is LIVE Boolean: set the SubTools to add (Union), subtract, or calculate intersections, preview the merged result in real time, then commit it with Make Boolean Mesh to get one watertight surface. Two things make it the go-to method for many artists. It works directly from the existing surfaces rather than resampling them, so it preserves your detail no matter the resolution. And it operates across every SubTool at once, automatically welding anything that overlaps, instead of forcing you to work one piece at a time.

DynaMesh is the classic alternative and still a solid option. As it remeshes into one continuous volume, it deletes the hidden internal surfaces where parts overlap and closes remaining gaps automatically. It has two trade-offs to keep in mind. It is a per-SubTool workflow, so a multi-part model has to be merged into one SubTool first, whereas LIVE Boolean handles all SubTools together. And because DynaMesh resamples the entire surface, you have to set the resolution high enough that fine detail is not lost. Either way, because slicers only read the outer surface, overlapping shapes inside the model are not a problem once they have been combined.

For very noisy scans or kitbashed concepts, DynaMesh still shines: a single high-resolution pass fuses everything into a clean, fully manifold base with minimal effort. Since a print model is usually decimated before export anyway, there is no need to add a ZRemesher pass here just to tidy the topology.

Scans are a great starting point that usually need some work. ZBrush lets you clean and reuse them rather than just patch them:

• Polygroups organize a scan into regions so you can isolate, hide or remove unwanted geometry quickly.

• The Slice brush cuts and separates areas of raw scan data, making it easy to trim away what you do not need.

• Projection transfers the fine detail from the original scan onto a cleaner, optimized mesh.

• LIVE Boolean combines scan data with other shapes in real time, whether for sculpting or building something new.

• You can turn a captured detail into a reusable VDM or IMM brush, so it can be reapplied to other models later.

If your model is destined for a mold rather than a direct print, ZBrush's Ready for Print analysis helps. Draw Draft Analysis colors surfaces green, yellow and red based on a chosen pull direction, so you can find and correct areas that would prevent a clean release, and Mask by Draft can generate a mask from those angles to help extract a negative mold.

Making the mesh watertight is the same core task in any package. If you also repair downloaded meshes in Cinema 4D, the concepts line up with the guide on how to fix 3D models for 3D printing. Once your ZBrush model is clean and closed, you can hollow it and reduce its polygon count before export.

Next: save material and verify thickness in how to hollow a ZBrush model and control wall thickness.