3 Keys to Preparing a Blender Model for 3D Printing

I wasted so much time and filament trying to get this right.

Ended up clogging my print head and having to replace my bowden tube on my Ender 3. So many failed prints. Frustratingly scraping half finished models off of the print bed. All because I didn’t know a few basic steps.

  1. Join the Objects
  2. Remesh
  3. Adjust the Voxel size

Do these 3 things to prepare a model made in Blender for printing.

Step 1: Join the Objects

Simple command: Ctrl + J

Here is a sample of a simple space ship I modeled before Joining. Notice the number of objects listed in the scene.

And this is the same object after joining all of the pieces.

This joins all of the selected objects into a single object. Simple first step.

Step 2: Remesh your new Object

This was the primary fix for the printing problems.

When you make your model and it has multiple parts, often they overlap in some way. This can be a major problem for the 3D printer. It may try to move the print head inside of an already created piece. When you Join the parts into a single object followed by a remesh, it removes the internal portions caused by overlap.

You add a remesh modifier by selecting the modifiers section (a small wrench icon shown below circled in red). Click the “add modifier” drop down and select “Remesh”.

Notice here the wireframe of the model before doing adding the remesh modifier. Even though it is a single object, it still shows some overlapping parts, which are problematic for printing.

And now see how it takes away the overlapping sections once the remesh is applied.

The remesh step does need some adjusting though. You can see even in this wireframe mode that some detail was lost when we applied the remesh.

Step 3: Adjust Voxel Size

The remesh caused most of my models to lose quite a bit of detail. You can see the object mode view here:

This is fixed by lowering the voxel size in the remesh control. I often had to reduce it to a very small number in order to return the detail that I wanted for my prints. See below where the voxel size is 0.015 compared to the 0.1 in the image above.

And the wireframe view:

Be careful if you are doing this on a machine with lower amounts of RAM. Lower voxel size means the model needs more memory to render and it can cause the program to crash. I did a typo and made it too small while testing on my laptop and Blender became unresponsive as it maxed out the system memory.

This should be the final step you need before exporting your .STL file for the slicer.

Other Potential Issues

Depending on the complexity of your model, you may have other issues printing it.

Sometimes people create gaps or tears in their model so that it is not complete. There are other tutorials about making sure your model is “water tight” and normalizing faces that we may cover in future posts.

These 3 steps should cover the basics for your beginner models.