What is the difference between Shape Height and Base Height in component properties?

Shape Height and Base Height are two separate controls in Component Properties. Both affect how high a component sits in the Z axis, but they work very differently.

Shape Height

Shape Height scales the height of the component's shape itself. It is a percentage of the component's current height (100%). Use the slider or type a value in the edit box.

• A component modeled 0.5 inch tall with Shape Height set to 50% appears 0.25 inch tall.
• The profile stays proportional: every point is scaled by the same factor.
• The slider range is based on your material thickness. If the range seems wrong you can still type any value, or correct the material thickness in Edit > Job Size and Position.

When to use Shape Height:

• A clipart component is too high or too flat for your material thickness.
• You want to reduce detail height proportionally to fit a shallower cut.
• You are assembling several components and need to balance their relative relief heights.

Base Height

Base Height raises the component up on a flat plane of the thickness you specify. It does not change the shape of the component, it only repositions it in Z. Base Height is a distance in job units, not a percentage.

• A component with Base Height 0.1 inch sits 0.1 inch above the modeling plane, with its own shape height added on top.
• A negative value lowers the component instead.
• If you are not sure what value you need, type an amount and press the Space Bar to apply it, look at the 3D view, and repeat until it looks right.

When to use Base Height:

• A component needs to sit proud of another component it is merging with.
• Two overlapping components need to appear at different depths without one cutting into the other.
• You want overlapping areas to clear each other without building a deep raised wall around a component's edge.
• A Level can also have its own Base Height, which raises everything on that Level together.

The Key Practical Difference

Shape Height changes the form. Base Height changes where the form sits.

Example: a leaf component 0.4 inch tall sits next to a rose component 0.3 inch tall, and they overlap at the edges. Rather than raising the whole rose Level, set a Base Height of 0.1 inch on the rose. It then sits 0.1 inch higher than the leaf where they overlap and appears in front of it.

This is useful for layered assemblies such as flowers, feathers, scales and moldings, where foreground elements must appear in front of background ones.

The Three Height Controls in the 3D View

When you select a component in the 3D view you can also drag the Total Height, Shape Height and Base Height controls. Model Height is the combined Shape Height plus Base Height. Increasing it increases both proportionally, and when Base Height is 0 a Model Height change leaves it at 0. You can reset a value to the component's default by double-clicking the Shape Height or Base Height icon in the 3D view.

Base Height, the Modeling Plane and Machine Z-Zero

These are separate things:

• Modeling plane: the reference plane where heights start in the 3D model. All components are measured from it.
• Machine Z-zero: set in Material Setup, at the top or bottom of the physical material.
• Model position in the material: set in Material Setup with Gap Above Model or Gap Below Model. The Modeling Plane Z field reports the resulting height of the modeling plane and cannot be edited directly.

Making a Dish

For a dish or recess, create a Round shape over the dish outline and set its Combine Mode to Subtract, leaving Base Height at 0. The dome's height is removed from the surface below. Do not also give the dome a negative Base Height: subtracting a shape that has been lowered below the modeling plane adds to the surface instead of cutting into it. Always check the result in the 3D view and test on scrap.

Important Note on Level Base Heights

When a Level has a Base Height:

• It visually raises all components on that Level.
• It is not included in Bake operations on the Level's components. It is a separate value added after the components are combined.
• It is scaled proportionately when you use Scale Model Z Height on the composite model.

Common Mistakes

• Using Base Height when Shape Height was intended. Base Height does not shrink the component, it only lifts it.
• Forgetting that Level Base Height is not baked when you bake individual components.
• Setting Base Height so high that the component rises above the material thickness. Check Material Setup.
• Confusing the modeling plane with machine Z-zero.