Rules for Dimensions

comments (0) February 12th, 2009 in blogs

Killenwood Tim Killen, contributor
thumbs up 6 users recommend

Dimensioning in SketchUp can be tricky, so I find it important to stick to some basic rules as follows:
1. Don't place dimensions within a component with one exception - dimensions for circles, arcs, and holes.
2. Keep dimensions into Layer 0 whenever possible
3. Don't clutter an overall view of a large component with detail dimensions
4. Create close-up views for detail dimensions on a copied component, or use a separate Layer for detail dimensions
5. Create multiple scenes to save these overall and close-up views, and in each scene show only those dimensions that are important

Here is more information on my Rule 1 above to avoid placing dimensions within a component definition:
• In a design package, there are always copies of components in multiple scenes. In most of these scenes the dimensions should not show. Therefore, layers must be created to avoid them showing up. I avoid using layers whenever possible as I get into trouble with lines and other entities ending up in the wrong layer.
• Dimensions (outside the component) in Layer 0 work well with components. For example, when moving the component the associated dimensions also move. I don't find any negative impacts of placing dimensions outside the component, but do find unacceptable outcomes when placing dimensions within the component.
• Dimensions within a component occasionally jump around in position and it is difficult to get them to stay where desired.

Here's an example of how I use the rules applied to a table leg:

Scene 1: This is typical of an overall view that I need in the design package. I cannot provide the detail dimensions on the joinery without cluttering-up the drawing. So my overall view includes only major dimensions. None of these dimensions are included in the component and they occur on the default Layer 0.


Scene 2: I make close-up views to show the detail dimensions, as this example shows for the top of the leg. In this case I have not made a copy of the leg component, rather added these dimensions to the same instance as above. These dimensions are placed on a new Layer called "Detailed dimensions". I create all these new dimensions in Layer 0, then later select each dimension and change to the detailed layer. I like to have the Layer Toolbar in my normal set up. In this way, when I select the dimension, I can go to the layer toolbar and change to the detail layer. This helps me avoid getting other entities, lines, components, etc. into the wrong layer.

Scene 3: Here's another close-up view with detail dimensions in the new layer. This view again is on the same instance of the component as in Scene 1. I make sure that these detail dimensions do not show up in Scene 1 by un-checking the "detail dimension" layer in Scene 1, then re-saving the Scene. If you don't re-save the Scene with this change in effected layers, you will see all the clutter of detail dimensions in Scene 1.

Note that there is a hole dimension in this scene. Dimensioning holes only works when you edit the component, so this is the only dimension that exists within the component dimension. This one is also changed to the detail layer so that it does not show up in non-applicable scenes.



posted in: blogs

Comments (0)

You must be logged in to post comments. Log in.

Save up to 51% on Fine Woodworking


Become a Better Woodworker

About Design. Click. Build.

Learn the art and science of designing furniture in SketchUp with Fine Woodworking's official blog. Moderated by a devoted community of woodworkers, we feature step-by-step SketchUp tutorials on designing components, downloads of pre-built 3D models of furniture parts, and news and information about the evolving world of digital furniture design.

Buy the Video
Don't miss Dave Richard's brand-new DVD/video download, The Basics.

Buy the Book
Get Tim Killen's popular eBook, the Google SketchUp Guide for Woodworkers.

Basic SketchUp Tutorials 
Learn the basics of building furniture in SketchUp with these classic posts from the Design. Click. Build. blog.

Creating a Project Plan in SketchUp
How I Draw in SketchUp
Axes in SketchUp
The SketchUp Move Tool
The SketchUp Rotate Tool
The SketchUp Scale Tool

Materials, Colors, and Textures
Applying Wood Grain Skins in SketchUp

Easy Dovetail Joints in SketchUp

Digital Project Plans

Download and modify SketchUp files for select projects from Fine Woodworking. View all.

Top Sellers:
Matt's Monster Workbench
New England Pine Cupboard
Garden Bench

Meet the Authors



I am a Biomedical Equipment Technician. I maintain anesthesia and respiratory equipment for the largest medical facility in southeast Minnesota. I...
view profile

Tim Killen

I am retired from Bechtel Corporation after 36 years in Engineering and IT management. I grew up among woodworking machinery in...
view profile


view profile