What Is the Your Model Is Not Manifold Error in Cura? (How to Fix?)

One of the most vital responsibilities of the slicer software is to confirm as best as possible that the model you have imported is actually printable by the 3D printer, as slicing a model that won’t print correctly will only result in time and material going to waste.

Because of this, slicer software, such as Cura, can sometimes prevent the printing process from moving forward by throwing an error that states the problem with the current model and ask you to fix it before you start to print.

Today, our topic is one such error, known as the “your model is not manifold” error in Cura, which is an issue that you may particularly face during the process of slicing models that are more on the complex side in terms of shape and detail.

So, what is the “your model is not manifold” message in Cura?

The “your model is not manifold” error in Cura is a warning that tells you the model you have imported is not watertight, meaning that there are gaps in the model that can cause the printing process to fail and even cause hardware damage to your 3D printer.

Next up, we will dive into the “your model is not manifold” error in more detail, find out what we can do to fix this error to continue with the printing process, and finally, take a quick look at a similar issue of your model is not watertight.

What Is the Your Model Is Not Manifold Error in Cura?

The “your model is not manifold” error in Cura could definitely be worded in a more user-friendly manner, especially considering that the explanation behind this error is pretty simple and not technical at all.

In a nutshell, the “your model is not manifold” message in Cura is a warning that informs you that the model you have imported not being watertight, which makes it unsuitable for 3D printing due to how slicer software operates.

While this message is merely a warning, meaning that you can ignore it and proceed with the printing process, slicing models that aren’t manifold is not recommended as it’s highly likely to cause a print failure or even hardware damage in more severe cases.

In most cases, this error results from barely noticeable gaps that remain on the model due to an oversight from the model’s creator, which Cura picks up and tells us about to ensure that we don’t face issues during the printing process later on.

If you are greeted with this message after importing a model into Cura, even if you aren’t able to see the problematic area with the Layer View feature (which means that the problem area is tiny but still exists, as we have mentioned), we highly recommend not ignoring it and fixing your model before proceeding with the print.

How to Fix the Your Model Is Not Manifold Error in Cura?

Since the reason behind the “your model is not manifold” error is as clear-cut as it comes, finding and applying the appropriate solution for the problem is a pretty straightforward process that shouldn’t be too much of a bother.

The most straightforward way to fix the “your model is not manifold” error in Cura is to download the Mesh Tools plugin and use its Fix Simple Holes feature, which can automatically repair your model by filling gaps and restoring its watertight status.

If you are not sure on how to download or use the Mesh Tools plugin for Cura, here is a quick step-by-step guide you can follow:

  1. Click the Marketplace button on the top-right corner of the Cura window.
  2. Click the Mesh Tools button in the Plugins tab of the Marketplace pop-up, which you can find under the Premium section that is visible without any scrolling.
  3. Click the Install button, and follow the process to add the Mesh Tools plugin to Cura, which will require you to restart Cura to finalize.
  4. Import the model you would like to fix once again.
  5. Right-click the model you would like to fix.
  6. Hover over the Mesh Tools option in the dropdown menu, and click the Fix Simple Holes option.

If Mesh Tools successfully repaired your model and made it manifold, you won’t see the “your model is not manifold” message from Cura anymore, which confirms that you are good to go.

While rare, in cases where the Mesh Tools plugin cannot repair your model, you will need to import your model into CAD software, such as Autodesk Meshmixer, and apply the necessary fixes there.

What Is the Your Model Is Not Watertight Error in Cura Mesh Tools?

A similar error to the “your model is not manifold” error in Cura is the “your model is not watertight” error, which is a related error that may sometimes appear if you have the Mesh Tools plugin installed.

The “your model is not watertight” error in Mesh Tools has the same meaning as Cura’s default “your model is not manifold”, which tells us that the model is unsuitable for 3D printing due to not being manifold/watertight.

While this message is definitely worded more clearly than Cura’s “not manifold” message, which may not make sense for a beginner, the result is nevertheless the same.

As this error is specific to the Mesh Tools plugin, you will only encounter it if you have the plugin installed.

Wrapping Up

While we can all agree that the “your model is not manifold” error in Cura does not give us a whole lot of detail about what the problem really is, the fact that it’s a helpful warning that prevents us from having a failed print is comforting.

To quickly recap, the message “your model is not manifold” in Cura, which sounds cryptic at first, actually conveys a crucial and straightforward warning about the printing process, telling us that the model we are trying to print is not watertight.

As a model that isn’t watertight is problematic for slicer software to slice accurately, ignoring this warning and proceeding with the printing process is highly likely to cause trouble, ranging from a print failure to hardware damage in the 3D printer.

Happy printing!