To help create lighter models, you can modify your designs so they'll be printed hollow.
There are a few things to keep in mind as you're getting ready to hollow your design:
- It's important to be aware of the Material Guidelines. Each material has its own set of guidelines that need to be considered in order to print a product successfully. These guidelines are designed based on the unique production process and physical traits for each material. For example, if you're designing for Sandstone, the minimum wall supported wall thickness is 2mm, but for Versatile Plastic it's much thinner at only 0.7mm.
- All hollow models require escape holes. This allows our production team to clean the inside of the model properly to remove excess print or support material that could get stuck in the cavity. Models that are designed to be hollow but don't have escape holes will automatically be solidified during the upload process, and will be printed solid. Check the Material Guidelines for specific escape hole requirements for each material.
How to Hollow out your Model
Using a cube as an example, let's take a look at the general process of creating a hollow model:
In a traditional 3D application, this cube will appear to consist of 6 faces with empty space in between. In 3D printing, however, it represents a solid volume.
One option to creating a hollow cube is to extrude the outer surface inwards, creating a scaled down version inside the original:
For more complex shapes, simply scaling the model inwards may not always give you the correct results. Instead, complex shapes will require some manual fixing.
Creating Escape Holes
Whenever a hollow model is being printed, the solidified area is surrounded by support material. When we remove the hollow model from the printers for cleaning, we need a way to clean this support material out from inside the model, that's where escape holes come into play.
Be sure to check the Material Guidelines for escape hole specifics for each material you're designing for.
Note: by hollowing your object and creating an escape hole, the number of polygons in your model will increase. The inside level of detail does not need to match the outside, therefore you can optimize your polygon count by lowering the number of polygons inside the model.