Introducing the Solid Tools in SketchUp Pro 8

Aidan Chopra

Every new SketchUp release contains at least one modeling tool that’s guaranteed to save you a ton of time and effort. SketchUp Pro 8 contains five.

The all-new Solid Tools let you perform additive and subtractive modeling tasks (some folks call them Boolean operations) on subsets of your geometry. It’s really not as complicated as it sounds; basically, you use the Solid Tools to generate forms using other forms in your models. You do so by adding them together, subtracting one from the other, and finding the areas that they have in common. Plenty of 3D forms are much easier to make this way – you’ll find uses for them all over the place.

Union takes two or more Solids and combines them into a single form.
Intersect creates a new Solid out of the parts of multiple Solids that overlap.
Subtract uses one Solid as a “cutting object” to remove part of another.
Trim (which is probably the most useful of the bunch) is a lot like Subtract, except that it doesn’t delete the Solid you use as a cutting object. Want to model joinery or other close-fitting parts? Trim is your tool.
Split takes two Solids and turns them into three; it’s a lot like doing two Subtract operations and an Intersect all at once.

Using the Solid Tools

... is a straightforward undertaking. Just activate the tool you want to use, then start clicking on Solids in your model. For Union, Intersect and Split, it doesn’t matter what order you go in. For Subtract and Trim, click the cutting object first, then the Solid you want that object to cut. It helps to think to yourself, “Use this to cut that” as you’re clicking.

More about Solids

The Solid Tools operate on a special class of entities called (you’ll never guess) Solids. Solids are nothing more than groups or components that:

are completely enclosed; you might say Solids are watertight, and
have no extra, loose edges or faces

Aside from letting you use the Solid Tools (which is pretty cool, we think) Solids are super-useful for another reason: SketchUp 8 (and SketchUp Pro 8) can calculate the volume of any Solid in your model. Just make a simple Solid and see for yourself. Here’s how:

Use the Rectangle Tool to draw a rectangle on the ground.
Push/Pull your rectangle into a box.
Select your new box (be sure to get all of it.)
Make a group by choosing Edit > Make Group from the menu bar. You’ve made a Solid!
Choose Window > Entity Info to open the Entity Info dialog box.
Select the group you made in Step 4. Its volume should appear near the bottom of the Entity Info dialog box.

The Wrap-Up

Both versions of SketchUp 8 (free and Pro) can make Solids and display their volumes in the Entity Info dialog box. If you want to include Volume as an attribute in a report you generate from your model, you’ll need SketchUp Pro 8. Similarly, you’ll need to have the Pro version of SketchUp 8 to use the brand new Solid Tools.