Hollowing Models

Some massing and site models do not require any strength and are merely formal representations. If these meet certain requirements, they can easily be printed hollow

When to Use These Settings

For models which don't require any strength, these settings can be used to reduce the print time and material usage. This is helpful if print time is excessive or if a very large volume of objects need to be processed. A typical example are massing blocks for site models.

You should consider using the Foam Cutters in the Forbo Model Making Space before proceeding. This is probably the quickest and most cost-effective method for creating massing models. Find out more here.

Design Requirements

These objects need to have a roof line that is flat in order to print successfully.

Figure 0.0 - This massing model is perfect for these hollow settings

IMAGE: 3D print a hollow model set/find an existing one and photograph.

While it is somewhat possible, these settings require more thought for objects with sloping or uneven roofs as they will print as overhangs and should be treated as such. This applies for objects with multiple or varying roof lines for similar reasons. Bear in mind that supports generated will equate to increased print time and as such, may negate the time saving benefits of hollow model printing. If you are not sure about what overhangs entail, please refer to our design guidelines which covers the topic of overhangs.

Modelling Guidelines

Figure 0.1 - Roofs are variable heights and sloping.

Settings Overview

The principle of hollow modelling is simple: you turn off infill and roof elements of your model.

This will effectively print the shells and floors of designed parts. As a result, students will need to flip each object in Makerbot print, placing the "roof" of each part facing down on the print bed. You can download the settings here.

Limitations

• The following parts are quite fragile, so they cannot take any weight

• The parts will have a rough roof finish, as the model's roofs will need to be removed from the raft

Figure 1.1 - Roofs are placed on the Print Bed

IMAGE: finished hollow model.

Default Settings

Feature	Recommended Setting
Print Mode	Balanced
Infill Density	0%
Roof Solid Thickness *	0 mm
Roof Surface Thickness	0 mm
Floor Thickness **	0.8 mm
Number of Shells ***	2
Layer Height (Shell)	0.3 mm
Layer Height (Infill)	0.3 mm
Support under Bridges	yes
Supports	Breakaway Support enabled

* This refers to the original model's base after flipping the model upside-down. ** 1.2 mm recommended if the student intends to sand the part. *** 3 Shells are recommended if the student intends to sand the part.